JP7014191B2 - Energization control device - Google Patents

Description

The present invention relates to an energization control device which is applied to an energization system for energizing a current from a power source to an apparatus via a power bus and has an overcurrent prevention function for preventing an overcurrent from being energized in the power bus.

For example, Patent Document 1 includes a lead storage battery charged by an alternator and a lithium storage battery electrically connected in parallel to the lead storage battery as an in-vehicle power source, and connects the lead storage battery and the lithium storage battery. A power supply device provided with an opening / closing means including a plurality of MOS-FETs for switching between energization and cutoff is described in the power bus.

Japanese Unexamined Patent Publication No. 2011-234479

For example, in the above-mentioned power supply device, if a power failure occurs such that the power bus connecting the lead storage battery and the lithium storage battery causes a ground fault at any point, the power bus from each storage battery becomes excessive toward the ground fault point. Current flows. If such an excessive current is left unattended, the capacity of each storage battery decreases in a short time, and the current for operating the in-vehicle device cannot be energized.

Therefore, it is conceivable to configure the power bus so that it can detect that an excessive current has flowed in the power bus, and to shut off the power bus by an opening / closing means (MOS-FET) when the excessive current is detected. As a result, at least the leakage of the current from the storage battery in which the current flows to the ground fault point via the opening / closing means can be stopped, and the in-vehicle device to which the current is supplied from the storage battery can continue to operate.

Excessive current can flow in either direction of the power bus, depending on where the power bus lands. At this time, if it is determined whether or not the current is excessive according to the same determination condition in any direction, there is a possibility that the detection sensitivity of the excessive current cannot be optimized. For example, in the power supply device described in Patent Document 1, the lead storage battery is directly connected to the alternator without using a switch or the like. Therefore, when the alternator generates power, the lead-acid battery is mainly charged by the generated power of the alternator. For this reason, it is expected that current will often flow in the power bus mainly in the direction from the lead storage battery to the lithium storage battery. In this way, when the normal current without any abnormality differs depending on the current flow direction, if the same judgment conditions are applied to both directions, the normal current is relatively small (or the normal current). In the current flow direction, there is an excessive margin to prevent the normal current from being erroneously detected as an excessive current, which causes a decrease in the detection sensitivity of the excessive current.

The present invention has been made in view of the above points, and when an excessive current flows in any direction of the power bus, the excessive current is detected with a detection sensitivity suitable for each direction. It is an object of the present invention to provide an energization control device capable of capable.

In order to achieve the above object, the energization control device (10) according to the present invention energizes an electric current from a power source (1, 6) to an apparatus (3, 4, 7) via a power bus (5, 8). It is applied to the system and prevents the power bus from being overcurrent.
The power source includes at least a first power source (1) and a second power source (6).
A changeover switch (11, 12) provided on the power bus connecting the first power supply and the second power supply and capable of switching between energization and interruption of current in the power bus, and
A switch drive unit (13) that drives the changeover switch to switch between a conduction state and a cutoff state, and
A current detector (14, 15) that detects the magnitude of the bidirectional current energized in the power bus, and
When it is determined that an overcurrent is energized in the power bus based on the magnitude of the current detected by the current detection unit, the overcurrent prevention control unit (16f) instructing the switch drive unit to drive the changeover switch to the cutoff state. , 19f), and
The overcurrent prevention control unit determines whether or not the current energized in one direction of the power bus corresponds to the overcurrent, and determines whether or not the current energized in the other direction corresponds to the overcurrent. , Uses different judgment conditions ,
The first power supply has at least one of the power supply capacity and the power supply voltage larger than that of the second power supply.
The overcurrent prevention control unit determines that the power bus is energized with an overcurrent based on the determination condition that the time when the magnitude of the current detected by the current detection unit exceeds the predetermined threshold value exceeds the predetermined duration. To detect
The overcurrent prevention control unit first determines whether or not the current energized in the first direction from the first power source to the second power source in the power bus corresponds to the overcurrent as a predetermined duration. Using the duration, the second duration, which is shorter than the first duration, is used to determine whether the current energized in the second direction opposite to the first direction corresponds to the overcurrent. It is a feature.

In the energization control device according to the present invention, as described above, in the overcurrent prevention control unit, it is determined whether or not the current energized in one direction of the power bus corresponds to the overcurrent, and the current is energized in the other direction. Different determination conditions are used to determine whether the current corresponds to an overcurrent. In other words, it is possible to set determination conditions according to the magnitude of the current in normal times for the current in each direction. Therefore, the energization control device according to the present invention makes it possible to detect an excessive current with a detection sensitivity suitable for the current in each direction.

The reference numbers in parentheses are merely examples of the correspondence with the specific configurations in the embodiments described below, and are intended to limit the scope of the invention in order to facilitate the understanding of the present disclosure. Not what I did.

Further, the technical features described in each claim of the claims other than the above-mentioned features will be clarified from the description of the embodiment described later and the attached drawings.

It is a block diagram which shows the schematic structure of the whole vehicle energization system including the energization control device provided with the overcurrent prevention function which concerns on 1st Embodiment. It is a block diagram which shows an example of the detailed structure of the energization control device of FIG. In the first embodiment, it is a flowchart which shows an example of the process executed in the controller of the energization control device in order to prevent energization of an overcurrent. In the first embodiment, it is a flowchart which shows the other example of the process executed in the controller of the energization control device in order to prevent energization of an overcurrent. It is a block diagram which shows an example of the detailed structure of the energization control device which concerns on 2nd Embodiment. It is a block diagram which shows an example of the characteristic structure of the drive circuit provided in the energization control device which concerns on 2nd Embodiment. It is a graph which shows how the time (time constant) until the changeover switch is switched to a conduction state changes depending on a resistance component. In the second embodiment, it is a flowchart which shows an example of the process executed in the controller of the energization control device in order to prevent energization of an overcurrent. It is a block diagram which shows an example of the detailed structure of the energization control device which concerns on 3rd Embodiment. It is a block diagram which shows an example of the characteristic structure of the drive circuit provided in the energization control device which concerns on 3rd Embodiment. It is a graph which shows how the time (time constant) until the changeover switch is switched to the conduction state changes depending on the drive method of the changeover switch. In the third embodiment, it is a flowchart which shows an example of the process executed in the controller of the energization control device in order to prevent energization of an overcurrent. It is a block diagram which shows an example of the detailed structure of the energization control device which concerns on 4th Embodiment. In the fourth embodiment, it is a flowchart which shows an example of the process executed in the controller of the energization control device in order to prevent energization of an overcurrent. In a fourth embodiment, it is a flowchart showing another example of the process executed in the controller of the energization control device in order to prevent energization of an overcurrent. It is a block diagram which shows the detailed structure of the modification of the energization control device which concerns on 4th Embodiment. It is a block diagram which shows the detailed structure of another modification of the energization control device which concerns on 4th Embodiment. It is a block diagram which shows the schematic structure of the whole vehicle energization system including the energization control device provided with the overcurrent prevention function which concerns on 5th Embodiment. It is explanatory drawing for demonstrating the problem to be solved of the energization control apparatus which concerns on 5th Embodiment. It is a block diagram which shows an example of the detailed structure of the energization control device of FIG. It is explanatory drawing for demonstrating the action effect obtained by the communication control apparatus which concerns on 5th Embodiment. It is a block diagram which shows the schematic structure of the whole vehicle energization system including the energization control device provided with the overcurrent prevention function which concerns on 6th Embodiment. In the vehicle energization system according to the sixth embodiment, it is a figure which shows the interrelationship of the current flowing through each part, and the current flowing through each part according to the power supply state, the current flowing through each electric power bus, and the operating state of an in-vehicle component. It is a flowchart which shows an example of the process for determining a current abnormality, which is executed in the controller of the energization control apparatus which concerns on 6th Embodiment. It is a block diagram which shows the schematic structure of the whole vehicle energization system including the energization control device which concerns on 7th Embodiment. It is a block diagram which shows an example of the structure of the energization control device which concerns on 7th Embodiment. (A) is a diagram conceptually showing the ground fault current flowing through the first power bus and the changeover switch when the second power bus in the vicinity of the sub power supply causes a ground fault, and (b) is a diagram showing (b). When a ground fault current such as a) flows, the time until the terminal voltage of the changeover switch drops below the threshold voltage and the voltage signal corresponding to the magnitude of the current flowing through the shunt resistor exceeds the threshold voltage. It is a figure which shows the time. (A) is a diagram conceptually showing the ground fault current flowing through the first power bus and the changeover switch when the second power bus in the vicinity of the switch terminal voltage detection circuit has a ground fault. (B) When a ground fault current such as (a) flows, the voltage signal corresponding to the time until the terminal voltage of the changeover switch drops below the threshold voltage and the magnitude of the current flowing through the shunt resistor sets the threshold voltage. It is a figure which shows the time until it exceeds. It is a flowchart which shows an example of the process flow for detecting a power source abnormality, which is executed in the energization control apparatus which concerns on 7th Embodiment. It is a block diagram which shows an example of the structure of the energization control device which concerns on 8th Embodiment. It is a flowchart which shows an example of the process flow for detecting a power source abnormality, which is executed in the energization control apparatus which concerns on 8th Embodiment. It is a block diagram which shows an example of the structure of the energization control device which concerns on 9th Embodiment. It is a flowchart which shows an example of the process flow for detecting a power source abnormality, which is executed in the energization control apparatus which concerns on 9th Embodiment. It is a block diagram which shows an example of the structure of the energization control device which concerns on 10th Embodiment. It is a flowchart which shows an example of the process flow for detecting a power source abnormality, which is executed in the energization control apparatus which concerns on 10th Embodiment. It is a block diagram which shows an example of the structure of the energization control device which concerns on 11th Embodiment. It is a block diagram which shows an example of the structure of the energization control device which concerns on 12th Embodiment. It is a flowchart which shows an example of the processing flow executed in the energization control apparatus which concerns on 12th Embodiment.

Hereinafter, a plurality of embodiments of the present invention will be described with reference to the drawings. In each embodiment, the same reference numerals may be given to the parts corresponding to the matters described in the preceding embodiments, and duplicate explanations may be omitted. When only a part of the configuration is described in each embodiment, other embodiments described above can be applied to the other parts of the configuration. In each embodiment, not only the combinations of the parts that clearly indicate that they can be combined, but also the embodiments as a whole and the embodiments as a whole, even if they are not specified, as long as there is no problem in the combination. / Or can be partially combined.

(First Embodiment)
FIG. 1 is a configuration diagram showing a schematic configuration of an entire energization system including an energization control device 10 having a function of preventing overcurrent as a power supply abnormality according to the first embodiment. In this embodiment, an example in which the energization control device 10 is applied to a vehicle energization system will be described. However, the energization control device 10 can also be applied to an energization system other than that for vehicles. First, a vehicle energization system to which the energization control device 10 is applied will be described.

The vehicle energization system shown in FIG. 1 has a main power source 1 and a sub power source 6 as an in-vehicle power source. Although only one main power source 1 and one sub power source 6 are shown in FIG. 1, a plurality of main power sources 1 and / or a plurality of sub power sources 6 may be provided as vehicle-mounted power sources.

These main power supply 1 and sub power supply 6 are secondary batteries that generate a voltage of, for example, about 12V. The main power supply 1 and the sub power supply 6 are connected to various in-vehicle components (first component 3, second component 4, third component 7, etc.) via a system main relay (not shown) and first and second power buses 5 and 8. ) Is connected. For example, when the system main relay is turned on in response to an operation of the vehicle start switch, the main power supply 1 and the sub power supply 6 supply operating power to various in-vehicle components.

The main power supply 1 has a battery capacity equal to or higher than the battery capacity of the sub power supply 6. Further, as shown in FIG. 1, the main power source 1 is directly connected to the generator (alternator) 2 mounted on the vehicle, and can be charged by the generator 2. The sub power source 6 can be charged by the generator 2 and / or the main power source 1 when the changeover switches 11 and 12 described later are in a conductive state. For example, when the vehicle is a hybrid vehicle having an engine and a drive motor as a power source, or an electric vehicle having a drive motor as a power source, and has a high voltage power source as a power source for the drive motor. The voltage of the high-voltage power supply may be stepped down by a DC-DC converter so that the main power supply 1 and the like can be charged.

In the present embodiment, the reason why a plurality of power sources such as the main power source 1 and the sub power source 6 are provided as the vehicle-mounted power source is that one power source fails or the first and second power buses 5 and 8 are used. This is to prevent all in-vehicle components from becoming inoperable even if a power failure such as a ground fault occurs at that location. In-vehicle components include, for example, components for driving engines and / or drive motors, components for driving braking devices, components for driving power steering devices, components for driving instrument devices, and air conditioning devices. It is a component for driving various devices mounted on the vehicle, such as a component for driving and a component for driving audio equipment. For example, in the configuration shown in FIG. 1, when the second power bus 8 connected to the sub power supply 6 has a ground fault, the changeover switches 11 and 12 are switched from the conduction state to the cutoff state, so that the main power supply 1 to the first power supply 1 And the power supply to the second components 3 and 4 can be continued normally. Thereby, for example, the first component 3 is an in-vehicle component including an actuator, a drive circuit, a controller, etc. for driving the engine and / or the drive motor of the vehicle, and the second component 4 is a braking device of the vehicle. In the case of an in-vehicle component including an actuator, a drive circuit, a controller, and the like for driving the vehicle, the vehicle can continue to travel even if the second power bus 8 has a ground fault.

Note that FIG. 1 shows only one set of changeover switches 11 and 12. However, a plurality of sets of changeover switches 11 and 12 may be provided on the first power bus 5 and the second power bus 8. At that time, in the first power bus 5 and the second power bus 8, a plurality of sets of changeover switches 11 and 12 can be provided so as to sandwich the branch point of the power bus to each in-vehicle component. By providing a plurality of sets of changeover switches 11 and 12, when a power failure occurs, it is possible to shut off the set of changeover switches 11 and 12 near the place where the changeover switch 11 and 12 occur. As a result, it is possible to increase the number of in-vehicle components that can continue to supply power as much as possible in the event of a power failure at a certain point.

Further, FIG. 1 shows a configuration in which the main power supply 1 and the sub power supply 6 are connected by one power bus 5 and 8, but the first power supply 1 and the sub power supply 6 are connected to each other. The power bus 5 and the second power bus 8 may be connected in a ring shape, that is, two power buses may be connected in parallel. Further, three or more power buses may be connected in parallel between the main power supply 1 and the sub power supply 6.

Next, the energization control device 10 according to the present embodiment will be described. As shown in FIG. 1, the energization control device 10 includes a set of changeover switches 11 and 12, a drive circuit 13, a shunt resistance 14, a current detection circuit 15, a current determination circuit 16, a voltage detection circuit 17 across the switch, and a voltage determination circuit. It includes 18 and a controller 19. An example of a specific configuration of each circuit will be described with reference to FIG.

In the present embodiment, one set of changeover switches 11 and 12 is connected between the first power bus 5 and the second power bus 8. Each of the set of changeover switches 11 and 12 is composed of a semiconductor switching element made of MOSFET. Due to the structure of MOSFET, a body diode (parasitic diode) is formed between drain and source. Therefore, even if the MOSFET is cut off, the current flows through the body diode, so that the bidirectional current cannot be cut off with only one MOSFET. In a vehicle energization system, a current may flow in both directions between the first power bus 5 and the second power bus 8. Therefore, in the present embodiment, a pair of MOSFETs in which the forward directions of the body diodes are opposite to each other are adopted as one set of changeover switches 11 and 12. As a result, when a power failure occurs, by setting both the changeover switches 11 and 12 in a cutoff state, the current can be completely cut off regardless of the direction in which the current flows.

The changeover switch is not limited to the MOSFET, and other semiconductor switching elements may be used. At this time, when a semiconductor switching element such as a so-called IGBT in which a body diode does not exist is adopted, the semiconductor switching element alone can be used as a changeover switch.

The drive circuit 13 sends an on drive signal for turning on the changeover switches 11 and 12 to the control terminals (gate terminals in the case of MOSFET) of the changeover switches 11 and 12 according to the changeover switch on / off drive signal from the controller 19. Output or output an off drive signal to turn off.

The shunt resistor 14 is connected to the first power bus 5 side of the changeover switches 11 and 12, and has the magnitude of the current flowing through the first power bus 5 and the second power bus 8 via the changeover switches 11 and 12. Generates the corresponding voltage. As shown in FIG. 2, the voltage on the second power bus 8 side of the changeover switches 11 and 12 is V1, the voltage between the changeover switches 11 and 12 and the shunt resistance 14 is V2, and the changeover switch 11 of the shunt resistance 14. The voltage on the opposite side of 12 is represented as V3. Then, for example, the voltage signal indicating the voltage difference between the voltages V2 and V3 across the shunt resistor 14 is represented as V23. The shunt resistor 14 may be provided on the second power bus 8 side of the changeover switches 11 and 12, or may be provided between the two changeover switches 11 and 12.

The current detection circuit 15 has a differential amplifier 15a, and a voltage signal V23 corresponding to the voltage difference between the voltages V2 and V3 across the shunt resistance 14 is passed through the first power bus 5 and the second power bus 8. Detects and outputs as the size of. As shown in FIG. 2, a reference voltage Vref-a is input to the non-inverting input terminal of the differential amplifier 15a. As a result, when the voltage V3 is higher than the voltage V2, the differential amplifier 15a outputs a voltage signal V23 higher than the reference voltage Vref-a by the amount corresponding to the voltage difference. On the other hand, when the voltage V2 is higher than the voltage V3, the differential amplifier 15a outputs a voltage signal V23 lower than the reference voltage Vref-a by the amount corresponding to the voltage difference. That is, the reference voltage Vref-a enables one differential amplifier 15a to output a voltage signal V23 corresponding to the voltage difference between the two voltages V2 and V3, regardless of the magnitude relationship between the voltage V2 and the voltage V3. Is for. However, the current detection circuit (differential amplifier) that detects the magnitude of the current flowing from the first power bus 5 to the second power bus 8 and the current flowing from the second power bus 8 to the first power bus 5 A current detection circuit (differential amplifier) for detecting the magnitude of the power may be provided separately.

The current determination circuit 16 includes two comparators 16a and 16b. One comparator 16a compares the voltage signal V23 output from the current detection circuit 15 with the threshold voltage Vth1 ⁽⁺⁾ , and the other comparator 16b compares the voltage signal V23 with the threshold voltage Vth1 ⁽⁻⁾ . .. The absolute value of the difference between the threshold voltage Vth1 ⁽⁺⁾ and the reference voltage Vref-a is equal to the absolute value of the difference between the threshold voltage Vth1 ⁽⁻⁾ and the reference voltage Vref-a.

As described above, when the voltage V3 is higher than the voltage V2, the current detection circuit 15 outputs a voltage signal V23 higher than the reference voltage Vref-a by the amount corresponding to the voltage difference. The comparator 16a of the current determination circuit 16 is based on the threshold voltage Vth1 ⁽⁺⁾ , and the voltage difference added to the reference voltage Vref-a included in the voltage signal V23 output at this time is at a level corresponding to the overcurrent. Determine if it exists. When the voltage signal V23 becomes larger than the threshold voltage Vth1 ⁽⁺⁾ , the comparator 16a outputs a Hi level signal indicating that the level corresponds to an overcurrent to the controller 19. On the other hand, when the voltage V2 is higher than the voltage V3, the current detection circuit 15 outputs a voltage signal V23 lower than the reference voltage Vref-a by the amount corresponding to the voltage difference. The comparator 16b of the current determination circuit 16 is based on the threshold voltage Vth1 ^(-) , and the voltage difference subtracted from the reference voltage Vref-a included in the voltage signal V23 output at this time is at a level corresponding to the overcurrent. Determine if it exists. When the voltage signal V23 becomes smaller than the threshold voltage Vth1 ⁽⁻⁾ , the comparator 16a outputs a Hi level signal indicating that the level corresponds to an overcurrent to the controller 19. As described above, the current determination circuit 16 compares the voltage signal V23 with the threshold voltages Vth1 ⁽⁺⁾ and Vth1 ⁽⁻⁾ in the two comparators 16a and 16b, so that the voltage signal V23 does not depend on the current energization direction. Can be determined whether is a level corresponding to an overcurrent or a level corresponding to a normal current in normal operation.

Further, the current determination circuit 16 includes a threshold value output circuit 16c. The threshold output circuit 16c changes the threshold voltages Vth1 ⁽⁺⁾ and Vth1 ⁽⁻⁾ used in the two comparators 16a and 16b in response to an instruction from the controller 19. This change of the threshold voltages Vth1 ⁽⁺⁾ and Vth1 ⁽⁻⁾ corresponds to one method of changing the overcurrent detection condition in the present embodiment so as to avoid erroneous detection of overcurrent. The change of the threshold voltages Vth1 ⁽⁺⁾ and Vth1 ⁽⁻⁾ based on the instruction from the controller 19 will be described in detail later.

The voltage detection circuit 17 across the switch has a differential amplifier 17a, and outputs a voltage signal V12 corresponding to the voltage difference between the voltages V1 and V2 across the switches 11 and 12. As shown in FIG. 2, the reference voltage Vref-b is also input to the non-inverting input terminal of the differential amplifier 17a of the voltage detection circuit 17 across the switch. As a result, when the voltage V2 is higher than the voltage V1, the differential amplifier 17a outputs a voltage signal V12 higher than the reference voltage Vref-b by the amount corresponding to the voltage difference. On the other hand, when the voltage V1 is higher than the voltage V2, the differential amplifier 17a outputs a voltage signal V12 lower than the reference voltage Vref-b by the amount corresponding to the voltage difference.

The voltage determination circuit 18 also includes two comparators 18a and 18b, like the current determination circuit 16. One comparator 18a compares the voltage signal V12 output from the voltage detection circuit 17 across the switch with the threshold voltage Vth2 ⁽⁺⁾ , and the other comparator 18b compares the voltage signal V12 with the threshold voltage Vth2 ^(-) . Compare. The absolute value of the difference between the threshold voltage Vth2 ⁽⁺⁾ and the reference voltage Vref-b is equal to the absolute value of the difference between the threshold voltage Vth2 ⁽⁻⁾ and the reference voltage Vref-b. Then, in the comparator 18a of the voltage determination circuit 18, when the voltage V2 is higher than the voltage V1, the voltage signal V12 corresponding to the voltage difference (that is, the voltage signal V12 larger than the reference voltage Vref-b) is the threshold voltage Vth2 ⁽ that is, the voltage signal V12 larger than the reference voltage Vref-b). When it becomes larger than ⁺⁾ , a Hi level signal indicating that the voltage difference is large is output to the controller 19. On the contrary, in the comparator 18b of the voltage determination circuit 18, when the voltage V1 is higher than the voltage V2, the voltage signal V12 corresponding to the voltage difference (that is, the voltage signal V12 smaller than the reference voltage Vref-b) is the threshold voltage Vth2. When it becomes smaller than ^(-) , a Hi level signal indicating that the voltage difference is large is output to the controller 19. As described above, the voltage determination circuit 18 compares the voltage signal V12 with the threshold voltages Vth2 ⁽⁺⁾ and Vth2 ⁽⁻⁾ in the two comparators 18a and 18b, and is based on the magnitude relationship between the voltage V1 and the voltage V2. Instead, it can be determined whether or not the voltage signal V12 corresponding to the voltage difference between the voltage V1 and the voltage V2 has a voltage difference larger than the threshold voltage Vth2 ⁽⁺⁾ and Vth2 ⁽⁻⁾ . In the state where the changeover switches 11 and 12 are cut off, if the voltage generated by the main power supply 1 is generally higher than the voltage generated by the sub power supply 6, the comparator 18b may be omitted. Further, the absolute value of the difference between the threshold voltage Vth2 ^{( +)} and the reference voltage Vref-b is made larger than the absolute value of the difference between the threshold voltage Vth2 ^(-) and the reference voltage Vref-b. ⁾ And Vth2 ^(-) as threshold values may be different.

For example, when the changeover switches 11 and 12 are switched from the cutoff state to the conduction state after the vehicle start switch is turned on, the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12 in the cutoff state is the main power supply 1. Depends on the voltage difference between the voltage generated by the sub power supply 6 and the voltage generated by the sub power supply 6. In other words, when the controller 19 tries to switch the changeover switches 11 and 12 from the cutoff state to the conduction state, the voltage detection circuit 17 across the switch is subordinate to the voltage of the main power supply 1 at the timing before switching to the continuation state. The voltage signal V12 can be output according to the voltage difference from the voltage of the power supply 6. When the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12 is relatively large, when the changeover switches 11 and 12 are switched to the conduction state, the first power bus 5 and the second power bus 8 A large current may flow between them via the changeover switches 11 and 12. Since the energization control device 10 according to the present embodiment includes the switch voltage detection circuit 17 across the switch and the voltage determination circuit 18 described above, the controller 19 has the voltages V1 and V2 across the switches 11 and 12 in the cutoff state. Based on the voltage difference, it is possible to detect in advance that a large current may flow when the changeover switches 11 and 12 are switched from the cutoff state to the conduction state.

The controller 19 may be configured by, for example, a microcomputer provided with a memory as a non-transitional and substantive storage medium in which the software is recorded non-temporarily, a processor for executing the software, an input / output interface, and the like. can. The controller 19 determines by software whether or not the condition for applying a large current to the power buses 5 and 8 is satisfied based on the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12, and the condition is satisfied. It is programmed to change the overcurrent detection condition so as to avoid erroneously detecting the large current as an overcurrent according to the determination.

In the above-described embodiment, an example in which the current detection circuit 15, the current determination circuit 16, the voltage detection circuit 17 across the switch, and the voltage determination circuit 18 are configured by hardware has been described. However, it is also possible to program the software so that the controller 19 executes the functions of each circuit configured by the hardware. For example, the voltages V1, V2, and V3 at various points of the power buses 5 and 8 are converted into digital signals by an A / D conversion circuit at appropriate timings and taken into the controller 19, and the current is detected by the controller 19 and the detected current. You may execute the determination of the size of.

Next, an example of the process executed by the controller 19 will be described with reference to the flowchart of FIG. The process shown in the flowchart of FIG. 3 is executed when the changeover switches 11 and 12 are switched from the cutoff state to the conduction state, for example, when the start switch of the vehicle is turned on.

In the first step S100, the controller 19 acquires the determination result of the voltage determination circuit 18. As described above, the voltage determination circuit 18 is one of the comparators 18a and 18b when the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12 exceeds the threshold voltages Vth2 ⁽⁺⁾ and Vth2 ^(-) . Outputs a Hi level signal to the controller 19. Therefore, in step S100, the controller 19 acquires the level of the signal output from the voltage determination circuit 18 as the determination result of the voltage determination circuit 18. In the following step S110, the controller 19 determines that the voltage signal V12 corresponding to the voltage difference between the voltage across the switches V1 and V2 is the threshold voltage Vth2 (Vth2 ⁽⁺⁾ , Vth2) based on the acquired output signal level of the voltage determination circuit 18. ^{(Including (-)} ) is exceeded. If it exceeds, it is considered that the condition that a large current is energized to the power buses 5 and 8 is satisfied based on the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12. In this case, the process proceeds to step S120 in order to change the overcurrent detection condition so as to avoid erroneously detecting the large current energized in the power buses 5 and 8 as an overcurrent. On the other hand, if the voltage signal V12 does not exceed the threshold voltage Vth2, the process of step S120 is skipped and the process proceeds to step S130.

In step S120, the overcurrent detection filter time is switched from the initial filter time T1 to the false detection prevention filter time T2 as a method of changing the overcurrent detection condition so as to avoid the false detection of the overcurrent. The overcurrent detection filter time is set to the initial filter time T1 by an initial process (not shown). The false detection prevention filter time T2 has a filter time longer than the initial filter time T1. The filter time is one requirement for the controller 19 to determine that the power buses 5 and 8 are energized with overcurrent. Specifically, the controller 19 determines that the power buses 5 and 8 are energized when the determination by the current determination circuit 16 that corresponds to the level of the overcurrent continues for the filter time. The filter time is for preventing erroneous detection of overcurrent when noise is superimposed on the power buses 5 and 8. By switching this filter time from the initial filter time T1 to the false detection prevention filter time T2, even if a large current is applied to the power buses 5 and 8, the possibility of falsely detecting the large current as an overcurrent is reduced. can do.

The filter time is not limited to switching from the initial filter time T1 to the false detection prevention filter time T2 in two stages. For example, in the voltage determination circuit 18, the magnitude of the voltage signal V12 corresponding to the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12 is stratified in multiple stages, and the magnitude of the stratified voltage signal V12 is set. Depending on the situation, the filter time may be configured to be switched in multiple stages. By doing so, it is possible to optimally set the filter time while suppressing erroneous detection of overcurrent.

In step S130, the controller 19 outputs a changeover switch-on drive signal to the drive circuit 13. As a result, the on drive signal for turning on the changeover switches 11 and 12 is output from the drive circuit 13, and the changeover switches 11 and 12 are switched from the cutoff state to the conduction state. In the following step S140, the controller 19 acquires the determination result of the current determination circuit 16. As described above, in the current determination circuit 16, the voltage signal V23 corresponding to the voltage difference between the voltages V2 and V3 across the shunt resistance 14 output by the current detection circuit 15 exceeds the threshold voltage Vth1 ⁽⁺⁾ , or Vth1 ^{( -)} When the level is below the level corresponding to the overcurrent, a Hi level signal is output from any of the comparators 16a and 16b. In the following description, it is mentioned that the voltage signal V23 exceeds the threshold voltage Vth1 ⁽⁺⁾ or falls below the threshold voltage Vth1 ^(-) , and that the voltage signal V23 exceeds the threshold voltages Vth1 ⁽⁺⁾ and Vth1 ^(-) . I have something to do. Therefore, in step S140, the controller 19 acquires the level of the signal output from the current determination circuit 16 as the determination result of the current determination circuit 16.

In the next step S150, whether or not the voltage signal V23 exceeds the threshold voltage Vth1 (including Vth1 ⁽⁺⁾ and Vth1 ^(-) ) based on the level of the output signal of the current determination circuit 16 acquired in step S140. Is determined. If it is determined in step S150 that the voltage signal V23 exceeds the threshold voltage Vth1, the process proceeds to step S160 to start a timer that counts the time when the voltage signal V23 exceeds the threshold voltage Vth1. On the other hand, if it is determined in step S150 that the voltage signal V23 does not exceed the threshold voltage Vth1, the process proceeds to step S170 to reset the timer.

In step S180, it is determined whether or not the timer count time is longer than the filter time (T1 or T2). If it is determined in this determination process that the timer count time is longer than the filter time, there is a possibility that a power failure such as a ground fault or power failure has occurred and the power buses 5 and 8 are energized with overcurrent. high. Therefore, the process proceeds to step S190, and the controller 19 outputs a changeover switch-off drive signal to the drive circuit 13. As a result, the changeover switches 11 and 12 are switched from the conduction state to the cutoff state. Therefore, even if a power failure occurs at any of the locations, it is possible to avoid a situation in which all the in-vehicle components become inoperable.

It is also possible to have the processing of steps S150 to S180 performed by the current determination circuit 16 instead of the controller 19. For example, whether the timer for measuring the filter time (T1 or T2) in the current determination circuit 16 and whether the Hi level signal output is continued from any of the comparators 16a and 16b over the filter time measured by the timer. By providing the determination circuit for determining whether or not, the current determination circuit 16 can execute the processes of steps S150 to S190. In this case, the controller 19 acquires the determination result from the current determination circuit 16 instead of the processing of steps S150 to S190, and determines whether to output the switch-off drive signal to the drive circuit 13 based on the determination result. You just have to do the processing. Alternatively, a filter circuit may be provided separately from the current determination circuit 16 so as to output the determination result of the current determination circuit 16 to the filter circuit, and the filter circuit may perform the processes of steps S160 to S180.

In step S200, a large current flows when the changeover switches 11 and 12 are switched to the conduction state due to the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12 in the cutoff state, and the large current is erroneously detected as an overcurrent. It is determined whether or not the filter time switching period, which is a period that may occur, has expired. This filter time switching period is set in advance as a period to which energization of a large current based on the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12 is completed. However, similarly to the multi-step switching of the filter time described above, the filter time switching period may be switched to another step according to the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12. When it is determined in step S200 that the filter time switching period has expired, the overcurrent detection filter time is returned from the false detection prevention filter time T2 to the initial filter time T1 in step S210. If the overcurrent detection filter time is not switched to the false detection prevention filter time T2, the overcurrent detection filter time does not change as the initial filter time T1 even if the process of step S210 is executed.

The controller 19 may execute the process shown in the flowchart of FIG. 4 in combination with or instead of the process shown in the flowchart of FIG. When the processing of the flowchart of FIG. 3 and the processing of the flowchart of FIG. 4 are executed in combination, the threshold voltage switching processing of step S121 described later may be executed together with the above-mentioned filter time switching processing. Hereinafter, the processing shown in the flowchart of FIG. 4 will be described. However, the processing of steps S100, S110, S130, S140, S160, S170, and S190 in the flowchart of FIG. 4 is the same as the processing of steps S100, S110, S130, S140, S160, S170, and S190 in the flowchart of FIG. Therefore, the description thereof will be omitted.

From the determination result of step S110 in the flowchart of FIG. 4, when it is considered that the condition that a large current is energized to the power buses 5 and 8 is satisfied based on the voltage difference between the voltage across the changeover switches 11 and 12 V1 and V2. In step S121 to be executed, as a method of changing the overcurrent detection condition so as to avoid erroneous detection of overcurrent, the overcurrent detection threshold voltage is set to the initial threshold voltage Vth1 (Vth1 ⁽⁺⁾ and Vth1 ^(-)) . (Including) is switched to the threshold voltage Vth1'(including Vth1' ⁽⁺⁾ and Vth1' ^(-) ) for preventing false detection. Specifically, the controller 19 instructs the threshold output circuit 16c of the current determination circuit 16 to switch the threshold voltage. The false detection prevention threshold voltage Vth1'is set to a value larger than the initial threshold voltage Vth1 as an absolute value. Therefore, the threshold output circuit 16c switches the overcurrent detection threshold voltage from the initial threshold voltage Vth1 to the false detection prevention threshold voltage Vth1'according to the instruction from the controller 19, so that a large current is generated in the power buses 5 and 8. Even when energized, the possibility of erroneously detecting the large current as an overcurrent can be reduced.

The threshold voltage is not limited to switching between the initial threshold voltage Vth1 and the false detection prevention threshold voltage Vth1'. For example, in the voltage determination circuit 18, the size of the voltage signal V12 corresponding to the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12 is layered in multiple stages, and the size of the layered voltage signal V12 is set. Depending on the situation, the threshold voltage may be configured to be switched in multiple stages. By doing so, it is possible to optimally set the threshold voltage while suppressing erroneous detection of overcurrent.

Then, in step S151 of the flowchart of FIG. 4, whether the voltage signal V23 exceeds the initial threshold voltage Vth1 or the false detection prevention threshold voltage Vth1'based on the level of the output signal of the current determination circuit 16 acquired in step S140. Judge whether or not. If it is determined in step S151 that the voltage signal V23 exceeds the initial threshold voltage Vth1 or the false detection prevention threshold voltage Vth1', the process proceeds to step S160. On the other hand, if it is determined in step S151 that the voltage signal V23 does not exceed the initial threshold voltage Vth1 or the false detection prevention threshold voltage Vth1', the process proceeds to step S170.

In step S181, it is determined whether or not the count time of the timer started in step S160 and reset in step S170 is longer than the filter time T1. If it is determined in this determination process that the timer count time is longer than the filter time T1, there is a possibility that a power failure such as a ground fault or a power failure has occurred and an overcurrent is being energized in the power buses 5 and 8. Is high. Therefore, the process proceeds to step S190, and the controller 19 outputs a changeover switch-off drive signal to the drive circuit 13. Similar to the description of the flowchart of FIG. 3, the processing of steps S151 to S181 may be performed by the current determination circuit 16 or a filter circuit separately provided.

Then, in step S201, it is determined whether or not the threshold voltage switching period has ended. This threshold voltage switching period is set in the same manner as the filter time switching period described above. When it is determined in step S201 that the threshold voltage switching period has ended, the overcurrent detection threshold voltage is returned from the false detection prevention threshold voltage Vth1'to the initial threshold voltage Vth1 in step S211. Unless the overcurrent detection threshold voltage is switched to the false detection prevention threshold voltage Vth1', the initial threshold voltage Vth1 does not change.

The process shown in the flowchart of FIG. 3 and the process shown in the flowchart of FIG. 4 described above are changes in the overcurrent detection conditions for avoiding erroneous detection of overcurrent, such as filter time, which is a requirement for determining overcurrent. It changes the threshold voltage. However, the overcurrent detection condition can be changed without changing the requirements such as the filter time and the threshold voltage. For example, when it is considered that the condition that a large current is energized to the power buses 5 and 8 is satisfied based on the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12, the controller 19 is set to the predetermined max time. , The overcurrent detection condition may be changed by stopping the overcurrent detection. Even in this way, it is possible to reduce the possibility that the large current energized in the power buses 5 and 8 is erroneously detected as an overcurrent.

(Second Embodiment)
Next, the energization control device according to the second embodiment of the present invention will be described with reference to FIGS. 5 to 8. In the energization control device 10 according to the first embodiment described above, as the overcurrent detection condition is changed, the filter time and the threshold voltage are changed, and the mask time for stopping the detection of the overcurrent is set. The purpose was to suppress erroneous detection of current. On the other hand, in the energization control device 10 according to the present embodiment, as a change of the overcurrent detection condition, the drive method of the changeover switches 11 and 12 is switched to suppress the erroneous detection of the overcurrent. Hereinafter, the energization control device 10 according to the present embodiment will be described focusing on the differences from the energization control device 10 according to the first embodiment. The switching of the drive methods of the changeover switches 11 and 12 according to the present embodiment, the change of the filter time and / or the threshold voltage, or the setting of the mask time according to the first embodiment may be carried out in combination.

FIG. 5 is a configuration diagram showing the configuration of the energization control device 10 according to the present embodiment. The energization control device 10 according to the present embodiment is configured in substantially the same manner as the energization control device 10 according to the first embodiment, and has the changeover switches 11 and 12, the drive circuit 13a, the shunt resistance 14, the current detection circuit 15, and the current determination circuit. 16. A voltage detection circuit 17 across a switch, a voltage determination circuit 18, and a controller 19a are provided. Among them, the circuit components and the electric circuits excluding the drive circuit 13a and the controller 19a are similarly configured in the first embodiment and the second embodiment. However, since it is not necessary to switch the threshold voltage in the present embodiment, the current determination circuit 16 is slightly different in that it does not have the threshold output circuit 16c capable of changing the threshold voltage as in the first embodiment.

In the present embodiment, as shown in FIG. 5, the controller 19a is based on the voltage difference between the voltage across the changeover switches 11 and 12 V1 and V2 in addition to the changeover switch on / off drive signal for the drive circuit 13a. The changeover switch drive method changeover signal is output according to whether or not the condition for energizing the power buses 5 and 8 with a large current is satisfied.

FIG. 6 is a configuration diagram showing an example of a characteristic configuration of the drive circuit 13a included in the energization control device 10 of the present embodiment. As shown in FIG. 6, in the drive circuit 13a, a parallel circuit of the resistance R1 and the resistance R2 is inserted in the transmission line for transmitting the drive signal to the control terminal of the changeover switch 11 (12). Further, in the parallel circuit, a time constant changeover switch is connected in series with the resistor R1. Although not shown, the drive circuit 13a has a drive signal output circuit that outputs a drive signal to the control terminal of the changeover switch 11 (12) via the transmission line described above, and a changeover switch drive method changeover signal from the controller 19a. It is equipped with a time constant changeover switch drive circuit that turns the time constant changeover switch on and off according to the situation.

The controller 19a drives the changeover switch to the drive circuit 13a when it is considered that the condition that a large current is energized to the power buses 5 and 8 is not satisfied based on the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12. When an on instruction signal instructing to turn on the time constant changeover switch is output as the method changeover signal, the time constant changeover switch is turned on in the drive circuit 13a, so that the resistance component of the transmission line is (R1 × R2). ) / (R1 + R2). On the other hand, the controller 19a switches to the drive circuit 13a when it is considered that the condition that a large current is energized to the power buses 5 and 8 is satisfied based on the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12. As a switch drive method changeover signal, an off instruction signal instructing to turn off the time constant changeover switch is output. Then, in the drive circuit 13a, the time constant changeover switch is turned off, so that the resistance component of the transmission line becomes R2.

In this way, the resistance component of the transmission line becomes smaller when the time constant changeover switch is turned on than when it is turned off. Therefore, when the drive signal is output from the drive signal output circuit to the control terminal of the changeover switch 11 (12) when the time constant changeover switch is turned on, a relatively large current flows through the transmission line. As a result, as shown in FIG. 7, the voltage VGS of the control terminal of the changeover switch 11 (12) rises sharply. Therefore, the time (time constant) until the changeover switch 11 (12) is switched to the conductive state becomes relatively short. In this case, as shown in FIG. 7, the current (inrush current) that flows when the changeover switch 11 (12) becomes conductive tends to increase. On the other hand, when the drive signal is output from the drive signal output circuit to the control terminal of the changeover switch 11 (12) when the time constant changeover switch is turned off, a relatively small current flows through the transmission line. As a result, as shown in FIG. 7, the voltage VGS of the control terminal of the changeover switch 11 (12) gradually increases. Therefore, the time (time constant) until the changeover switch 11 (12) is switched to the conductive state becomes relatively long. In other words, the time for the semiconductor switching element constituting the changeover switch 11 (12) to transition from the cutoff state to the conduction state becomes relatively long. As a result, as shown in FIG. 7, it is possible to suppress the inrush current when the changeover switch 11 (12) is switched to the conduction state. As a result, even if the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12 is large and a large current flows when the changeover switches 11 and 12 are switched to the conduction state, the large current is erroneously overcurrented. It is possible to suppress the detection as.

FIG. 8 is a flowchart showing an example of processing executed by the controller 19a of the present embodiment. Hereinafter, the process executed by the controller 19a will be described with reference to the flowchart of FIG. However, the processing of steps S100, S110, S130, S140, S150, S160, S170, S181, and S190 in the flowchart of FIG. 8 is performed in steps S100, S110, S130, S140, S150, and S160 of the flowchart of FIGS. , S170, S181 and S190, so the description thereof will be omitted.

From the determination result of step S110 in the flowchart of FIG. 8, when it is considered that the condition that a large current is energized to the power buses 5 and 8 is satisfied based on the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12. In step S122 to be executed, as a method of changing the overcurrent detection condition so as to avoid erroneous detection of overcurrent, the resistance component of the transmission line connected to the control terminals of the changeover switches 11 and 12 and transmitting the drive signal. Is higher than usual. Specifically, the controller 19a outputs an off instruction signal instructing the drive circuit 13a to turn off the time constant changeover switch. When the time constant switch of the drive circuit 13a is turned off, the resistance component of the transmission line becomes higher than the normal resistance component, as described above.

On the other hand, in step S123, which is executed when it is considered that the condition that a large current is energized to the power buses 5 and 8 is not satisfied based on the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12, the changeover switch 11 , The resistance component of the transmission line that transmits the drive signals of 12 is set to a low resistance component as usual. Specifically, the controller 19a outputs an on instruction signal instructing the drive circuit 13a to turn on the time constant changeover switch. When the time constant switch is turned on, as described above, the resistance component of the transmission line becomes a normal resistance component lower than the resistance component for preventing overcurrent.

Therefore, when the changeover switch-on drive signal is output to the drive circuit 13a in step S130, the drive circuit 13a has a time constant according to whether or not the condition that a large current is energized to the power buses 5 and 8 is satisfied. The changeover switches 11 and 12 can be switched to the conductive state. Therefore, it is possible to reduce the possibility that the large current flowing through the power buses 5 and 8 is erroneously detected as an overcurrent.

Then, in step S202 of the flowchart of FIG. 8, it is determined whether or not the time constant changeover switch changeover period has expired. The time constant changeover switch changeover period is set in the same manner as the filter time changeover period described in the first embodiment. When it is determined in step S202 that the time constant changeover switch changeover period has expired, in step S212, an on instruction signal instructing the drive circuit 13a to turn on the time constant changeover switch is output. As a result, the resistance component of the transmission line becomes a normal resistance component lower than the resistance component for preventing overcurrent, and when the changeover switch off signal is output to the changeover switches 11 and 12, the changeover switch is quickly shut off. It is possible to switch.

(Third Embodiment)
Next, the energization control device according to the third embodiment of the present invention will be described with reference to FIGS. 9 to 12. The energization control device 10 according to the second embodiment described above switches the drive method of the changeover switch by switching the resistance component of the transmission line that transmits the drive signals of the changeover switches 11 and 12, and suppresses erroneous detection of overcurrent. It was intended to be. On the other hand, the energization control device 10 of the present embodiment switches the drive method of the changeover switch by switching whether the changeover switches 11 and 12 are driven by voltage or constant current, and erroneous detection of overcurrent is detected. It is intended to be suppressed. Hereinafter, the energization control device 10 according to the present embodiment will be described focusing on the differences from the energization control device 10 according to the second embodiment.

FIG. 9 is a configuration diagram showing the configuration of the energization control device 10 according to the present embodiment. The energization control device 10 according to the present embodiment is configured in the same manner as the energization control device 10 according to the second embodiment, and has the changeover switches 11 and 12, the drive circuit 13b, the shunt resistance 14, the current detection circuit 15, and the current determination circuit 16. , A voltage detection circuit 17 across the switch, a voltage determination circuit 18, and a controller 19b. Of these, the circuit components and each electric circuit excluding the drive circuit 13b and the controller 19b are configured in the same manner as in the second embodiment.

In the present embodiment as well, as in the second embodiment, as shown in FIG. 9, the controller 19b has a voltage across the changeover switches 11 and 12 in addition to the changeover switch on / off drive signal for the drive circuit 13b. Based on the voltage difference between V1 and V2, the changeover switch drive method changeover signal is output depending on whether or not the condition for energizing the power buses 5 and 8 with a large current is satisfied.

FIG. 10 is a configuration diagram showing an example of a characteristic configuration of the drive circuit 13b included in the energization control device 10 of the present embodiment. As shown in FIG. 10, the drive circuit 13b is configured so that the changeover switch 11 (12) can be driven by either voltage drive or constant current drive. For example, although not shown, the drive circuit 13b includes a drive signal output circuit that outputs a drive signal to the control terminal of the changeover switch 11 (12), and a voltage drive switch according to the changeover switch drive method changeover signal from the controller 19b. It is equipped with a switch drive circuit that turns on one of the constant current drive switches and turns off the other. In the drive circuit 13b, when the voltage drive switch is turned on and the constant current drive switch is turned off, the drive signal output by the drive signal output circuit is the changeover switch 11 via the voltage drive switch and the parallel circuit of the resistors R1 and R2. It is applied to the control terminal of (12). In this case, the changeover switch 11 (12) is voltage-driven by the drive signal. On the other hand, in the drive circuit 13b, when the voltage drive switch is turned off and the constant current drive switch is turned on, the drive signal output by the drive signal output circuit is supplied to the constant current circuit via the constant current drive switch. In this case, a constant current generated by a constant current circuit is supplied to the control terminal of the changeover switch 11 (12), and the changeover switch 11 (12) is driven with a constant current.

The controller 19b drives the changeover switch to the drive circuit 13a when it is considered that the condition that a large current is energized to the power buses 5 and 8 is not satisfied based on the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12. A voltage drive instruction signal for instructing voltage drive is output as a method switching signal. Then, in the drive circuit 13b, the voltage drive switch is turned on and the constant current drive switch is turned off. On the other hand, the controller 19b switches to the drive circuit 13b when it is considered that the condition that a large current is energized to the power buses 5 and 8 is satisfied based on the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12. A constant current drive instruction signal for instructing constant current drive is output as a switch drive method switching signal. Then, in the drive circuit 13b, the voltage drive switch is turned off and the constant current drive switch is turned on.

In the present embodiment, as shown in FIG. 11, when the changeover switch 11 (12) is driven by a voltage, the time (time constant) at which the changeover switch 11 (12) switches from the cutoff state to the conduction state is relatively short, and is driven by a constant current. When, the time constant is set to be long. Therefore, when the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12 is not large and a large current does not flow when the changeover switches 11 and 12 are switched to the conduction state, voltage drive is adopted. By doing so, the changeover switches 11 and 12 can be quickly switched to the conductive state. On the other hand, when the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12 is large and a large current flows after the changeover switches 11 and 12 are switched to the conduction state, constant current drive is adopted. In the present embodiment, the time constant until the changeover switches 11 and 12 are switched to the conductive state by the constant current drive is longer than the time constant by the voltage drive, so that the changeover switches 11 and 12 are switched to the conductive state. It is possible to suppress the inrush current at the time of occurrence, and it is possible to reduce the possibility that the inrush current is erroneously detected as an overcurrent.

In the above example, the time constant for switching the changeover switches 11 and 12 by voltage drive to the conduction state is set to be shorter than the time constant for switching the changeover switches 11 and 12 by constant current drive to the continuity state. .. However, it is also possible to set the time constant for switching the changeover switches 11 and 12 to the conduction state by constant current drive to be shorter than the time constant for switching the changeover switches 11 and 12 to the continuity state by voltage drive. ..

FIG. 12 is a flowchart showing an example of processing executed by the controller 19b of the present embodiment. Hereinafter, the process executed by the controller 19b will be described with reference to the flowchart of FIG. However, the processing of steps S100, S110, S130, S140, S150, S160, S170, S181 and S190 in the flowchart of FIG. 12 is performed in steps S100, S110, S130, S140, S150, S160, S170 and S181 of the flowchart of FIG. Since it is the same as the processing of S190 and S190, the description thereof will be omitted.

From the determination result of step S110 in the flowchart of FIG. 12, when it is considered that the condition that a large current is energized to the power buses 5 and 8 is satisfied based on the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12. In step S124 to be executed, the drive method of the changeover switches 11 and 12 is changed to constant current drive as one method of changing the overcurrent detection condition so as to avoid erroneous detection of overcurrent. Specifically, the controller 19b outputs a constant current drive instruction signal instructing constant current drive to the drive circuit 13b as a changeover switch drive method changeover signal. As a result, in the drive circuit 13b, the voltage drive switch is turned off, the constant current drive switch is turned on, and preparations for constant current drive of the changeover switches 11 and 12 are carried out.

On the other hand, in step S125, which is executed when it is considered that the condition that a large current is energized to the power buses 5 and 8 is not satisfied based on the voltage difference between the voltages V1 and V2 across the changeover switches 11 and 12, the changeover switch 11 , 12 drive methods are voltage drive. Specifically, the controller 19b outputs a voltage drive instruction signal instructing voltage drive to the drive circuit 13b as a changeover switch drive method changeover signal. As a result, in the drive circuit 13b, the voltage drive switch is turned on, the constant current drive switch is turned off, and preparations for voltage driving of the changeover switches 11 and 12 are carried out.

Therefore, in step S130, when the controller 19b outputs the changeover switch-on drive signal to the drive circuit 13b, the drive circuit 13b depends on whether or not the condition that a large current is energized to the power buses 5 and 8 is satisfied. , Either voltage drive or constant current drive can be executed to switch the changeover switches 11 and 12 to the conduction state. Therefore, it is possible to reduce the possibility that the large current flowing through the power buses 5 and 8 is erroneously detected as an overcurrent.

Then, in step S203 of the flowchart of FIG. 12, it is determined whether or not the drive method switching period has expired. This drive method switching period is set in the same manner as the filter time switching period described above. When it is determined in step S203 that the drive method switching period has expired, in step S213, the drive circuit 13b is instructed to turn on the voltage drive switch and turn off the constant current drive switch. As a result, when the changeover switch off signal is output to the changeover switches 11 and 12, the changeover switch can be quickly switched to the cutoff state.

The method of changing the time constant when switching the changeover switch to the conduction state is not limited to the second and third embodiments described above. For example, the drive signal output circuit in the drive circuit 13 can be switched between outputting a drive signal having a predetermined voltage from the beginning and outputting a drive signal whose voltage gradually increases toward the predetermined voltage as the drive signal. Configure to. Then, when the time constant at which the changeover switches 11 and 12 are switched to the conduction state is shortened, a drive signal of a predetermined voltage is applied to the control terminals of the changeover switches 11 and 12, and when the time constant is lengthened, the changeover is performed. A drive signal whose voltage gradually increases toward a predetermined voltage may be applied to the control terminals of the switches 11 and 12.

(Fourth Embodiment)
Next, the energization control device according to the fourth embodiment of the present invention will be described with reference to FIGS. 13 to 17. In the energization control device 10 according to the first to third embodiments described above, whether or not the condition that a large current is energized to the power buses 5 and 8 is satisfied is determined by the voltage across the changeover switches 11 and 12 in the cutoff state. The determination was made based on the voltage difference between V1 and V2. On the other hand, the energization control device 10 according to the present embodiment is, in other words, when at least one in-vehicle device is driven by the in-vehicle component that drives the in-vehicle device in such a manner that a large current is energized in the in-vehicle component. Therefore, when the in-vehicle component is regarded as a part of the in-vehicle device, when at least one in-vehicle device is operated in such a manner that the in-vehicle device is energized with a large current, a large current is applied to the power buses 5 and 8. It is considered that the condition for energizing is satisfied.

Then, when the energization control device 10 according to the present embodiment is deemed to satisfy the condition that a large current is energized in the power buses 5 and 8, the filter time and / or the threshold voltage is changed as a change of the overcurrent detection condition. At least one of the change of, the setting of the mask time, and the change of the drive method of the changeover switch is carried out. This point is the same as the energization control device 10 according to the first to third embodiments described above.

FIG. 13 is a configuration diagram showing an example of the configuration of the energization control device 10 according to the present embodiment. As shown in FIG. 13, the energization control device 10 according to the present embodiment includes the changeover switches 11, 12, the drive circuit 13, the shunt resistance 14, the current detection circuit 15, the current determination circuit 16, the controller 19c, the component controller 20, and the component controller 20. The component actuator 21 is provided. Of these, the circuit components and each electric circuit excluding the controller 19c, the component controller 20, and the component actuator 21 are configured in the same manner as in the first embodiment. Therefore, the description of these similar configurations will be omitted. Although FIG. 13 shows only one set of the component controller 20 and the component actuator 21 as in-vehicle components, in reality, a plurality of sets of the component controller and the component actuator 21 are provided.

The energization control device 10 according to the present embodiment shown in FIG. 13 is not provided with the voltage detection circuit 17 across the switch and the voltage determination circuit 18. However, the energization control device 10 according to the present embodiment also has these configurations, and controls for suppressing erroneous detection of overcurrent similar to the energization control device 10 according to the first to third embodiments described above. It is also possible to do it. That is, the energization control device 10 according to the present embodiment may be implemented in combination with the energization control device 10 according to the first to third embodiments.

The component controller 20 outputs an actuator drive signal to the component actuator 21 according to the operation of the driver of the vehicle or the state of the vehicle or the actuator to control the operation of the component actuator 21. As described above, the component actuator 21 is an actuator for driving an in-vehicle device such as a power steering device or a brake device. The component actuator 21 has a sensor that detects the operating state (for example, steering operation amount and brake operation amount) of the in-vehicle device to be driven by the actuator, and outputs the detection signal detected by the sensor to the controller 19c and the component controller 20. do.

When the component controller 20 outputs, for example, an actuator drive signal for causing the power steering device to perform a sudden steering or an actuator drive signal for causing the braking device to perform a sudden braking, the component controller 20 is before or before the output. At the same time as the output, a sudden steering signal and a sudden braking signal are output to the controller 19c. When the power steering device is made to steer suddenly or the braking device is made to suddenly brake, the corresponding in-vehicle device is driven in such a manner that a large current is applied to the in-vehicle component. Therefore, when the controller 19c receives a sudden steering wheel signal or a sudden braking signal from the component controller 20, it is considered that the condition that a large current is energized to the power buses 5 and 8 is satisfied. The sudden steering signal and the sudden braking signal are merely examples, and the controller 19c is a signal indicating that a large current is applied to an in-vehicle component of another in-vehicle device (for example, a sudden acceleration by a drive motor). Of course, it is also possible to consider that the condition that a large current is energized to the power buses 5 and 8 is satisfied by receiving a signal (a signal, a Maxcool signal in an air conditioner, etc.).

Then, when it is considered that the condition that a large current is energized to the power buses 5 and 8 is satisfied, the controller 19c changes the overcurrent detection condition as described in the first to third embodiments. Therefore, even when a large current flows through the power buses 5 and 8 due to the normal operation of the in-vehicle device, the possibility of erroneously detecting the large current as an overcurrent can be reduced.

It is premised that the energization control device 10 of the first to third embodiments described above includes a plurality of power sources as an in-vehicle power source. That is, it is determined whether or not the condition for energizing the power buses 5 and 8 is satisfied based on whether or not the voltage difference between the voltages generated by the plurality of power sources is large. On the other hand, the energization control device 10 according to the present embodiment has a condition that a large current is energized to the power buses 5 and 8 based on the information that a large current is required for the operation of the in-vehicle device (component actuator). It is considered to have been established. Therefore, the energization control device 10 according to the present embodiment is applied not only to a vehicle energization system having a plurality of power sources such as a main power source 1 and a sub power source 6, but also to a vehicle energization system having only one power source. It is also possible.

The flowchart of FIG. 14 shows the filter time by changing the filter time when the controller 19c considers that the condition that a large current is energized to the power buses 5 and 8 is satisfied based on the sudden steering signal, the sudden braking signal, and the like. The processing when changing the overcurrent detection condition is shown.

That is, if it is determined in step S300 that one or more of a sudden steering wheel signal and a sudden braking signal has been received from the component controller 20, the controller 19c proceeds to the process of step S310 and sets the overcurrent detection filter time to a filter for preventing false detection. Set to time T2. On the other hand, if it is determined in step S300 that one or more of the sudden steering signal and the sudden braking signal have not been received, the controller 19c skips step S310 and proceeds to the process of step S320.

Since the processing of steps S320 to S390 in the flowchart of FIG. 14 is the same as the processing of steps S140 to S210 of the flowchart of FIG. 3, the description thereof will be omitted. However, in the flowchart of FIG. 14, it is necessary to continuously determine whether a sudden steering wheel signal, a sudden braking signal, or the like is output from the component controller 20. Therefore, if a negative determination is made in step S380, or if the process of step S390 is completed, the process returns to the process of step S300.

The flowchart of FIG. 15 shows the flowchart of FIG. 15 by changing the threshold voltage when the controller 19c considers that the condition that a large current is energized to the power buses 5 and 8 is satisfied based on the sudden steering signal, the sudden braking signal, and the like. The processing when changing the overcurrent detection condition is shown.

That is, if it is determined in step S300 that one or more of the sudden steering signal and the sudden braking signal have been received, the controller 19c proceeds to the process of step S315 and sets the overcurrent detection threshold voltage to the false detection prevention threshold voltage Vth1'(. Vth1' ⁽⁺⁾ and Vth1' ^(-) are included). On the other hand, if it is determined in step S300 that one or more of the sudden steering signal and the sudden braking signal have not been received, the controller 19c skips the process of step S315 and proceeds to the process of step S320.

Note that the processing of steps S320, S335, S340, S350, S365, S370, S385, and S395 in the flowchart of FIG. 15 is performed in steps S140, S151, S160, S170, S181, S190, S201, and S211 of the flowchart of FIG. Since it is the same as the process of, the description thereof will be omitted. However, in the flowchart of FIG. 15, it is necessary to continuously determine whether a sudden steering wheel signal, a sudden braking signal, or the like is output from the component controller 20. Therefore, when a negative determination is made in step S385 and when the process of step S395 is completed, the process returns to the process of step S300.

As shown in FIG. 13, the controller 19c of the energization control device 10 according to the present embodiment is a sensor of the component actuator 21 by the controller 19c itself in addition to or instead of the sudden steering wheel signal and the sudden braking signal from the component controller 20. Based on the steering operation amount and the brake operation amount output from the vehicle, it may be determined that the steering wheel or the brake is suddenly executed.

Further, as shown in FIG. 13, the component controller 20 of the energization control device 10 according to the present embodiment outputs an actuator drive signal for causing a sudden steering and an actuator drive signal for causing the braking device to perform a sudden braking. Before or at the same time as the output, the overcurrent detection mask signal may be output to the controller 19c for a period corresponding to the energization period of a large current instead of the sudden handle signal or the sudden braking signal. As a result, the controller 19c stops the detection of the overcurrent during the energization period of the large current, so that it is possible to prevent the erroneous detection of the overcurrent.

Further, by providing the controller 19c and the component controller 20 as in the energization control device 10 according to the present embodiment, abnormality detection other than overcurrent detection (temperature abnormality, overvoltage abnormality, etc.) can be appropriately detected from the component controller 20. By instructing the controller 19c to mask, the possibility of erroneous detection for an abnormality other than overcurrent can be reduced. Further, it is possible to prevent the changeover switch from being shut off by resetting the controller 19c at a timing when it is not desirable to shut off the changeover switch. Specifically, when a predetermined reset condition is satisfied, a reset signal is output to the controller 19c from a reset circuit (not shown). Before the reset signal is output from the reset circuit, the component controller 20 is configured to receive the output information of the reset signal from the reset circuit in advance. The component controller 20 determines whether or not reset is possible based on whether or not the system is in a system state in which there is no problem even if the changeover switches 11 and 12 are temporarily cut off from the voltage level of each location, and the determination result signal. To the reset circuit. When the reset circuit receives the determination result signal that the reset is possible, the reset circuit outputs a reset signal to the controller 19c, and the controller 19c is reset.

Alternatively, even if the controller 19c is reset, a holding circuit for holding the output of the on drive signal from the drive circuit 13 may be provided during the reset period.

Further, the energization control device 10 according to the fourth embodiment may be modified and implemented as shown in FIG. In the energization control device 10 shown in FIG. 16, the controller 19c and the component controller 20 of the energization control device 10 shown in FIG. 13 are integrated into one controller 22. By doing so, communication between the controller 19c and the component controller 20 becomes unnecessary, so that the processing speed can be increased.

Further, the energization control device 10 according to the fourth embodiment may be modified and implemented as shown in FIG. In the energization control device 10 shown in FIG. 17, in addition to the sudden steering wheel signal and the sudden braking signal from the component controller 20, the sudden steering wheel warning signal and the sudden braking warning signal are input from the ADAS controller 23 to the controller 19e.

The ADAS controller 23 is connected to various sensor groups 24, detects the surrounding conditions of the vehicle by so-called LIDAR and image sensors, and grasps the driving status of the vehicle from the vehicle speed sensor, steering sensor, accelerator sensor, etc., and the vehicle. Controls to prevent and reduce contact with surrounding objects. When the ADAS controller 23 determines that it is necessary to operate the brake or operate the steering wheel in order to avoid or reduce contact with an object in front of the vehicle, for example, a sudden steering warning signal or a sudden braking warning signal Is output to the controller 19e. When the controller 19e receives such a sudden handle warning signal or a sudden braking warning signal from the ADAS controller 23, it is predicted that the in-vehicle device (component actuator) will be operated in such a manner that a large current is energized. , The overcurrent detection condition may be changed on the assumption that the condition for energizing the power buses 5 and 8 with a large current is satisfied.

(Fifth Embodiment)
Next, the energization control device according to the fifth embodiment of the present invention will be described with reference to FIGS. 18 to 21. FIG. 18 is a configuration diagram showing a schematic configuration of the entire vehicle energization system including the energization control device 10 having a function of preventing overcurrent as a power supply abnormality according to the present embodiment.

As shown in FIG. 18, the energization control device 10 according to the present embodiment can be applied to a vehicle energization system having the same configuration as described in the first embodiment. Further, the basic configuration of the energization control device 10 according to the present embodiment is the same as that of the energization control device 10 according to the first embodiment. However, in the energization control device 10 according to the first embodiment, the current determination circuit 16 includes two comparators 16a and 16b, and the voltage signal V23 when the voltage V3 is higher than the voltage V2 sets the threshold voltage Vth1 ⁽⁺⁾ . When it exceeds, the comparator 16a outputs a Hi level signal indicating that the energization current is at a level corresponding to an overcurrent, and the voltage signal V23 when the voltage V2 is higher than the voltage V3 exceeds the threshold voltage Vth1 ^(-) . The comparator 16b has been described as outputting a Hi level signal indicating that the energizing current is at a level corresponding to an overcurrent. On the other hand, in the energization control device 10 according to the present embodiment, the comparator 16a is represented as a forward direction determination circuit 16a as shown in FIG. 18 in order to further clarify the characteristic points of the energization control device 10 of the present embodiment. , The comparator 16b is represented as a negative direction determination circuit 16b. Regarding other circuits, that is, the drive circuit 13, the current detection circuit 15, the voltage detection circuit 17 across the switch, and the voltage determination circuit 18, the energization control device 10 according to the fifth embodiment is also the energization control device according to the first embodiment. It is configured in the same manner as 10.

In the energization control device 10 according to the first embodiment, even if the directions of the currents flowing through the power buses 5 and 8 are different, does the current flowing through the power buses 5 and 8 correspond to an overcurrent using the same determination conditions? It was judged whether or not. The problems that occur in this case will be described with reference to FIG. As shown in FIG. 18, the “forward current” in FIG. 19 means the current flowing through the power buses 5 and 8 in the direction from the main power supply 1 to the sub power supply 6. Further, as shown in FIG. 18, the “negative current” in FIG. 19 means a current flowing through the power buses 5 and 8 in the direction from the sub power source 6 to the main power source 1.

As described in the first embodiment, the main power supply 1 has a battery capacity equal to or higher than the battery capacity of the sub power supply 6. Further, the main power source 1 is directly connected to the generator (alternator) 2 mounted on the vehicle, and when the generator 2 generates electric power, the main power source 1 is charged by the generated electric power. For this reason, the power buses 5 and 8 often have a current flowing mainly in the direction from the main power supply 1 to the sub power supply 6, and the positive current tends to be larger than the negative current. The graph of FIG. 19 depicts the relationship between the magnitudes of the positive current and the negative current in a comparable manner.

More specifically, the voltage difference between the main power supply 1 and the sub power supply 6 when the changeover switches 11 and 12 are in the cutoff state is the voltage difference in which the positive current flows rather than the voltage difference in which the negative current flows. Tends to be larger. Therefore, when the changeover switches 11 and 12 are switched from the cutoff state to the conduction state and the current starts to flow in the power buses 5 and 8, the magnitude of the positive current is larger than the magnitude of the negative current as shown in FIG. Is also likely to grow. In the example shown in FIG. 19, when the voltage difference between the voltage across the changeover switches 11 and 12 in the cutoff state is large, when the changeover switches 11 and 12 are switched from the cutoff state to the conduction state, a predetermined period T ^{(+). )} , T ^(-) (corresponding to the filter time switching period of the first embodiment), the first overcurrent so as not to mistakenly detect the large current flowing through the power buses 5 and 8 as an overcurrent. The detection process is performed. In this first overcurrent detection process, the threshold currents It1 ⁽⁺⁾ and Is1 ⁽⁻⁾ having the same magnitude with respect to the positive current and the negative current (threshold voltage Vth1'for overcurrent prevention of the first embodiment (1) ^{( +)} , Vth1' ^(-) ), filter time of the same length t1 ⁽⁺⁾ , t1 ^(-) (corresponding to the false detection prevention filter time T2 of the first embodiment) Current is detected. Further, also in the second overcurrent detection process after the predetermined period T ⁽⁺⁾ and T ^(-) have elapsed and the magnitude of the current flowing through the power buses 5 and 8 has converged to the magnitude in normal times. Threshold currents of the same magnitude, Is2 ⁽⁺⁾ and Is2 ^(-) (corresponding to the initial threshold voltages Vth1 ⁽⁺⁾ and Vth1 ^(-) of the first embodiment) and the same length with respect to the positive and negative currents. Overcurrent detection is performed using the determination conditions based on the filter times t2 ⁽⁺⁾ and t2 ⁽⁻⁾ (corresponding to the initial filter time T1 of the first embodiment).

As described above, in the first overcurrent detection process and the second overcurrent detection process, when the overcurrent is detected for the forward current and the negative current using the same determination conditions, it is clear from FIG. As described above, the margins of the threshold currents It1 ^{(− )} and Is2 (−) for the relatively small negative current are excessive so as not to be erroneously detected as an overcurrent. As a result, the detection sensitivity for detecting that the negative current is excessive is lowered. In the graph of FIG. 19, the threshold currents Is1 (+ ⁾ and Is2 ⁽⁺⁾ with respect to the positive current in the first and second overcurrent detection processes, and the overcurrent may cause a failure in the energization control device 10. The margins α1 and α2 with the generated region are the threshold currents Is1 (− ⁾ and Is2 ⁽⁻⁾ for the negative current in the first and second overcurrent detection processes, and the overcurrent may cause a failure in the energization control device 10. The margins β1 and β2 with the region where the sex occurs are equal to each other.

On the other hand, in the energization control device 10 of the present embodiment, as shown in FIG. 20, the threshold output circuit 16c has the comparator 16a as the positive direction determination circuit and the comparator 16b as the negative direction determination circuit as absolute values. It is configured to output threshold voltages Vth1a ⁽⁺⁾ and Vth1b ^(-) of different magnitudes. More specifically, in the first and second overcurrent detection processes, the absolute values of the threshold voltages Vth1a' ⁽⁺⁾ and Vth1a ⁽⁺⁾ are the absolute values of the threshold voltages Vth1b' ^(-) and Vth1b ^(-) , respectively. Is set larger than. As a result, as shown in FIG. 21, the magnitudes of the threshold currents Is1 (+ ⁾ and Is2 ⁽⁺⁾ used for determining the overcurrent of the positive current in the first and second overcurrent detection processes are the negative currents. The absolute value is larger than the magnitudes of the threshold currents Is1'( ^-) and Is2' ^(- ) used for the overcurrent determination. Conversely, the magnitudes of the threshold currents It1' ^{( -)} and Is2'(-) used for determining the overcurrent of the negative current as absolute values are adapted to the magnitude of the relatively small negative current. To be reduced.

Further, in the present embodiment, in the controller 19f, the first and second overcurrent detection processes are performed so that the filter time used for determining the overcurrent of the positive current and the filter time used for determining the overcurrent of the negative current are different. The filter time in can be set. Specifically, as shown in FIG. 21, the lengths of the filter times t1 ⁽⁺⁾ and t2 ⁽⁺⁾ used for determining the overcurrent of the positive current in the first and second overcurrent detection processes are, respectively. It is set longer than the lengths of the filter times t1 ⁽⁻⁾ and t2 ⁽⁻⁾ used for determining the overcurrent of the negative current. In addition, in the controller 19f, as shown in FIG. 21, a predetermined period T ⁽⁺⁾ for executing the first overcurrent detection process for the positive current is set, and the first overcurrent detection process is performed for the negative current. Is longer than the predetermined period T ^(-) for executing. Thereby, the filter time and the execution period of the first overcurrent detection process can also be adapted to the magnitudes of the positive current and the negative current and their changes.

In the first overcurrent detection process executed when the changeover switches 11 and 12 are switched from the cutoff state to the conduction state when the voltage difference between the voltage across the changeover switches 11 and 12 in the cutoff state is large, the threshold value is reached. At least one of the change of and the change of the filter time may be made. Further, it is also optional to make the execution period of the first overcurrent detection process different between the positive current and the negative current. That is, the first overcurrent detection process may be executed for the same period. Further, the first overcurrent detection process may be executed when the vehicle-mounted device (vehicle-mounted component) is operated in a mode in which a large current is energized.

According to the energization control device 10 according to the present embodiment, as described above, it is determined whether or not the positive current corresponds to the overcurrent and whether or not the negative current corresponds to the overcurrent. , Different judgment conditions are used. In other words, for the current in each direction, it is possible to set the determination condition according to the magnitude of the current in normal times and its change. Therefore, it becomes possible to detect an overcurrent with a detection sensitivity suitable for the current in each direction. Further, as a result of adapting the detection sensitivity to the negative current, as shown in FIG. 21, the margins β'1 and β'2 with the region where a failure may occur in the energization control device 10 are expanded. can do.

(Sixth Embodiment)
Next, the energization control device 10 according to the sixth embodiment of the present invention will be described with reference to FIGS. 22 to 24. FIG. 22 is a configuration diagram showing a schematic configuration of the entire vehicle energization system including the energization control device 10 according to the present embodiment.

As shown in FIG. 22, the energization control device 10 according to the present embodiment has the changeover switches 11 and 12 and the shunt resistance 14 connected to the first power bus 5 between the main power supply 1 and the fourth component 9. Has. Further, the energization control device 10 according to the present embodiment is a current detection circuit that detects the magnitude of the current flowing in both directions of the power bus 5 from the voltage across the drive circuit 13 for driving the changeover switches 11 and 12 and the shunt resistance 14. 15. The current determination circuit 16g is provided with the current determination circuit 15 and the current determination circuit 16g for determining the current based on the detection result of the current detection circuit 15.

The current determination circuit 16g determines whether the positive direction current I1 ⁽⁺⁾ is at a level corresponding to the overcurrent and the negative direction current I1 ⁽⁻⁾ is at a level corresponding to the overcurrent. Negative direction determination circuit 16b and the like. Further, in the present embodiment, a voltage signal indicating a voltage difference between the voltages across the shunt resistance 14 including information on the direction and magnitude of the current flowing through the first power bus 5 is transmitted from the current detection circuit 15 to the controller 19g. Is also configured to be entered. The controller 19g can grasp the direction and magnitude of the current flowing through the power bus 5 by A / D converting and capturing this voltage signal. That is, in the current detection circuit 15, for example, the reference voltage Vref-a is input to the non-inverting input terminal of the differential amplifier 15a, as in the first embodiment. Therefore, when the differential amplifier 15a has a voltage difference in which a current flows in the positive direction across the shunt resistance 14, the differential amplifier 15a outputs a voltage signal higher than the reference voltage Vref-a by the amount corresponding to the voltage difference. Output. On the other hand, when the differential amplifier 15a has a voltage difference across the shunt resistance 14 in which a current flows in the negative direction, the differential amplifier 15a outputs a voltage signal lower than the reference voltage Vref-a by the amount corresponding to the voltage difference. do. Therefore, the controller 19g can grasp the direction and magnitude of the current flowing through the first power bus 5 based on the voltage signal output from the current detection circuit 15.

As described above, in the energization control device 10 of the present embodiment, in addition to detecting that the controller 19g is flowing a current at a level corresponding to an overcurrent in any direction of the power bus 5, the first method is performed. It is configured so that the magnitude of the current in the power bus 5 and the energization direction thereof can be detected. In FIG. 22, L1 represents the wiring inductance of the first power bus 5.

Further, as shown in FIG. 22, the energization control device 10 according to the present embodiment has the changeover switches 111 and 112 and the shunt connected to the second power bus 8 between the sub power source 6 and the fourth component 9. It has a resistance 114. Further, the energization control device 10 according to the present embodiment is a current detection circuit that detects the magnitude of the current flowing in both directions of the power bus 5 from the voltage across the drive circuit 113 for driving the changeover switches 111 and 112 and the shunt resistance 114. It has 115 and 116 g of a current determination circuit that determines a current based on the detection result of the current detection circuit 115.

The current determination circuit 116g also has the same configuration as the above-mentioned current determination circuit 16g. That is, the current determination circuit 116g has a positive direction determination circuit 116a for determining whether the positive current I2 ⁽⁺⁾ is at a level corresponding to an overcurrent and a negative current I2 ⁽⁻⁾ at a level corresponding to an overcurrent. Includes a negative direction determination circuit 116b for determining whether or not. Further, in the present embodiment, a voltage signal indicating the voltage difference between the voltages across the shunt resistance 114, including information on the direction and magnitude of the current flowing through the second power bus 8, is transmitted from the current detection circuit 115 to the controller 19g. It is configured to be entered. The controller 19g can grasp the direction and magnitude of the current flowing through the second power bus 8 by A / D converting and capturing this voltage signal.

As described above, the energization control device 10 of the present embodiment detects that a current corresponding to an overcurrent is flowing in any direction of the second power bus 8, and in addition, the second power is generated. It is configured to be able to detect the magnitude of the current in the bus 8 and the direction of energization thereof. In FIG. 22, L2 represents the wiring inductance of the second power bus 8.

The fourth component 9 connected to the power buses 5 and 8 between the main power supply 1 and the sub power supply 6 operates by being energized with current from the main power supply 1 and / or the sub power supply 6. The shunt resistor 25 is connected to the energization path from the power buses 5 and 8 of the fourth component 9. Further, a load current detection circuit 26 is provided that detects the magnitude of the load current IL energized in the fourth component 9 by a voltage signal corresponding to the voltage difference between the voltages across the shunt resistor 25. The voltage signal from the load current detection circuit 26 is input to the controller 19g. The controller 19g can grasp the magnitude of the load current IL based on the voltage signal from the load current detection circuit 26.

As described above, in the energization control device 10 according to the present embodiment, the controller 19g has the magnitude of the current flowing through the first power bus 5 and its energization direction, and the magnitude of the current flowing through the second power bus 8 and its own. It is configured so that the energization direction and the magnitude of the load current IL can be grasped. The controller 19g can detect a current abnormality in the energization control device 10 based on the magnitude of these currents and the energization direction. That is, once the system configuration of the vehicle energization system, the detection position by the current detection circuits 15, 26, 115, etc. are determined, the mutual relationship between the directions and the magnitudes of the currents detected by the current detection circuits 15, 26, 115. Etc. are determined by the operating state of the in-vehicle component and the power supply state from each of the power supplies 1 and 6.

FIG. 23 shows the power supply state from the power supplies 1 and 6 when the vehicle energization system and the energization control device 10 are configured as shown in FIG. 22, and the operating state of the fourth component 9 which is an in-vehicle component. , Is a chart showing the interrelationship between the direction of the current flowing in each part and the magnitude of the current.

For example, when the voltage generated by the main power supply 1 is higher than the voltage generated by the sub power supply 6, power is supplied from the main power supply 1 to the sub power supply 6, or from the main power supply 1 to the sub power supply 6 and the fourth component 9. .. In this case, as shown in FIG. 23, if the fourth component 9 is sleeping and the load current IL is zero, the forward current I1 ⁽⁺⁾ flows through the first power bus 5, and the second component is second. A positive current I2 (+ ⁾ equal to the positive current I1 ⁽⁺⁾ flows through the power bus 8. On the other hand, when the fourth component 9 is waked and the load current IL corresponding to the operating state thereof flows to the fourth component 9, the forward current I1 ⁽⁺⁾ flows through the first power bus 5. A positive current I2 (+) equal to the result of subtracting the load current IL from the positive current I1 ^{( +)} flows through the second power bus 8.

Further, when the voltage generated by the main power supply 1 and the voltage generated by the sub power supply 6 are equal to each other, when the fourth component 9 is sleeping, no current is applied to the power buses 5 and 8. On the other hand, when the 4th component 9 is waked up, power is supplied from the main power source 1 and the sub power source 6 to the 4th component 9. At this time, as shown in FIG. 23, a positive current I1 ⁽⁺⁾ flows through the first power bus 5. A negative current I2 ⁽⁻⁾ flows through the second power bus 8. Then, between the positive current I1 ⁽⁺⁾ of the first power bus 5 and the negative current I2 ⁽⁻⁾ of the second power bus 8, I2 ⁽⁻⁾ = I1 ⁽⁺⁾ × (L1 /). The relationship of L2) holds. Further, considering the load current IL, between the positive current I1 ⁽⁺⁾ of the first power bus 5 and the negative current I2 ⁽⁻⁾ of the second power bus 8, I1 ⁽⁺⁾ + I2 ^{( -)} = IL relationship holds.

Therefore, when a current that does not satisfy the mutual relationship of the direction and magnitude of the current is detected, it is highly probable that a current abnormality has occurred in the vehicle energization system or the energization control device 10. Therefore, the controller 19g of the energization control device 10 according to the present embodiment has a predetermined current direction and magnitude according to the power supply state from the power supplies 1 and 6 and the operation state of the fourth component 9 which is an in-vehicle component. It was decided to detect the current abnormality by using the mutual relationship. Hereinafter, an example of the processing executed by the controller 19g to detect the current abnormality will be described with reference to the flowchart of FIG. 24.

First, in step S400, it is determined whether or not the power supply state is a state in which power is supplied from the main power supply 1 to the sub power supply 6. For example, in the power supply state, whether the forward current I1 ⁽⁺⁾ or the negative current I1 ^(-) is flowing in the first power bus 5, or whether the current is flowing, and the second power bus 8 It can be determined based on whether the positive current I2 ⁽⁺⁾ or the negative current I2 ⁽⁻⁾ is flowing, or whether the current is not flowing. That is, when the forward current I1 ^{(+) flows through the first power bus 5 and the forward current I2 (+) also} flows through the second power bus 8, the power supply state is sub from the main power supply 1. It can be determined that power is being supplied to the power source 6. However, regarding the determination of the power supply state, for example, the controller 19g can read and determine the voltage generated by the main power supply 1 and the voltage generated by the sub power supply 6. If it is determined in step S400 that the power is being supplied from the main power supply 1 to the sub power supply 6, the process proceeds to step S410. On the other hand, if it is determined in step S400 that the power supply is not in the power supply state from the main power supply 1 to the sub power supply 6, the process proceeds to step S450.

In step S410, the controller 19g determines whether or not the fourth component 9 is sleeping by communicating with the controller of the fourth component 9, for example, and acquiring information on the operating state of the fourth component 9. If it is determined that the fourth component 9 is sleeping, the process proceeds to step S420. On the other hand, if it is determined that the fourth component 9 is not sleeping, the process proceeds to step S430.

In step S420, the controller 19g causes a forward current I1 ⁽⁺⁾ to flow in the first power bus 5 and a second power bus 8 in the second power bus 8 based on the direction and magnitude of the detected currents in each part. It is determined whether or not the relationship that the positive current I2 ⁽⁺⁾ equal to the positive current I1 ⁽⁺⁾ of the power bus 5 of 1 is flowing is established. If it is determined that this relationship is established, no current abnormality has occurred, so the controller 19g returns to the process of step S400. On the other hand, if it is determined that this relationship is not established, the process proceeds to step S440, and it is determined that a current abnormality has occurred.

In step S430, the controller 19g causes a forward current I1 ⁽⁺⁾ to flow in the first power bus 5 and a first in the second power bus 8 based on the direction and magnitude of the detected currents in each part. It is determined whether or not the relationship that the positive current I2 ⁽⁺⁾ equal to the result of subtracting the load current IL from the positive current I1 ⁽⁺⁾ of the power bus 5 is flowing is established. If it is determined that this relationship is established, no current abnormality has occurred, so the controller 19g returns to the process of step S400. On the other hand, if it is determined that this relationship is not established, the process proceeds to step S440, and it is determined that a current abnormality has occurred.

When the controller 19b determines that the current is abnormal, for example, the changeover switches 11 and 12 and / or the changeover switches 111 and 112 are switched to the cutoff state to cause a failure of the energization control device 10 or a malfunction of the fourth component 9. It is preferable to avoid such things.

In step S450, it is determined whether or not the power supply state is a state in which power is supplied from the main power supply 1 and the sub power supply 6 to the fourth component 9. For example, when the positive current I1 ⁽⁺⁾ is flowing in the first power bus 5 and the negative current I2 ⁽⁺⁾ is flowing in the second power bus 8, the power supply state is the main power supply 1 and the sub power supply. It can be determined that power is supplied from 6 to the 4th component 9. If it is determined in step S450 that the power is supplied from the main power supply 1 and the sub power supply 6 to the fourth component 9, the process proceeds to step S460. On the other hand, if it is determined in step S450 that the power supply state is not such that power is supplied from the main power supply 1 and the sub power supply 6 to the fourth component 9, the process proceeds to another power supply state determination process (not shown).

In step S460, it is determined whether or not the fourth component 9 is sleeping. If it is determined that the fourth component 9 is sleeping, the process proceeds to step S470. On the other hand, if it is determined that the fourth component 9 is not sleeping, the process proceeds to step S480.

In step S470, the controller 19g has neither positive current I1 ⁽⁺⁾ nor negative current I1 ⁽⁻⁾ flowing through the first power bus 5 based on the direction and magnitude of the detected currents of each part. Moreover, it is determined whether or not the relationship that neither the positive current I2 ⁽⁺⁾ nor the negative current I2 ⁽⁻⁾ is flowing in the second power bus 8 is established. If it is determined that this relationship is established, no current abnormality has occurred, so the process returns to step S400. On the other hand, if it is determined that this relationship is not established, the process proceeds to step S490, and it is determined that a current abnormality has occurred.

In step S480, the controller 19g causes a forward current I1 ⁽⁺⁾ to flow in the first power bus 5 and a first in the second power bus 8 based on the direction and magnitude of the detected currents in each part. It is determined whether or not the relationship that the result obtained by adding the positive current I1 ⁽⁺⁾ of the power bus 5 of the above is equal to the load current IL and the negative current I2 ⁽⁻⁾ is flowing is established. If it is determined that this relationship is established, no current abnormality has occurred, so the controller 19g returns to the process of step S400. On the other hand, if it is determined that this relationship is not established, the process proceeds to step S490, and it is determined that a current abnormality has occurred.

As described above, according to the energization control device 10 according to the present embodiment, the direction and magnitude of the detected currents of the respective parts depend on the power supply state from the power supplies 1 and 6 and the operating state of the fourth component 9. It is possible to detect a current abnormality depending on whether or not a predetermined mutual relationship between the direction and the magnitude of the current is satisfied.

(7th Embodiment)
Next, the energization control device 10 according to the seventh embodiment of the present invention will be described with reference to FIGS. 25 to 29. FIG. 25 is a configuration diagram showing a schematic configuration of the entire vehicle energization system including the energization control device 10 according to the present embodiment.

The energization control device 10 according to the first to fourth embodiments described above does not erroneously detect the large current as an overcurrent when it is considered that the condition for energizing the power buses 5 and 8 is satisfied. As described above, the overcurrent detection condition was changed and the drive method of the changeover switch was changed. On the other hand, the energization control device 10 according to the present embodiment suppresses erroneous detection when an overcurrent is actually energized in the power buses 5 and 8, and at the earliest possible time, the overcurrent is energized. It is designed to be detectable.

As shown in FIG. 25, the energization control device 10 according to the present embodiment can be applied to a vehicle energization system having the same configuration as described in the first embodiment. Further, as shown in FIG. 25, the energization control device 10 according to the present embodiment has the changeover switches 11 and 12, the drive circuit 13, the shunt resistance 14, the current detection circuit 15, the current determination circuit 16, and the switch terminal voltage detection circuit 27. , A filter circuit 28 and a controller 19h. Among them, the circuit components and each electric circuit excluding the controller 19h, the switch terminal voltage detection circuit 27, and the filter circuit 28 are configured in the same manner as in the first embodiment.

FIG. 26 is a configuration diagram showing an example of the configuration of the energization control device 10 according to the present embodiment. The switch terminal voltage detection circuit 27 detects whether or not the terminal voltage V1 on the second power bus 8 side of the changeover switches 11 and 12 is larger than the predetermined threshold voltage Vth3. That is, the switch terminal voltage detection circuit 27 outputs a Lo level signal when the terminal voltage V1 is larger than the predetermined threshold voltage Vth3, and outputs a Hi level signal when the terminal voltage V1 is not larger than the predetermined threshold voltage Vth3. That is, the switch terminal voltage detection circuit 27 detects a voltage abnormality as a power supply abnormality when the terminal voltage V1 drops and falls below the threshold voltage Vth3. The switch terminal voltage detection circuit 27 is not the terminal voltage V1, but the voltage VM at the midpoint between the changeover switches 11 and 12, the terminal voltage V2 on the first power bus 5 side, or the terminal voltage straddling the shunt resistance 14. It may be one that detects V3. This is because these voltages are short-circuited with low resistance via the changeover switches 11 and 12 or the shunt resistor 14, so that they can be regarded as substantially the same potential.

The filter circuit 28 outputs the OR circuit 29 that outputs the Hi level signal and the output signal of the OR circuit 29 when the Hi level signal is output from any of the two comparators 16a and 16b of the current determination circuit 16. It has an AND circuit 30 having one input and an output signal from the switch terminal voltage detection circuit 27 as the other input. Further, the filter circuit 28 is provided with a first filter 31, a second filter 32, and a third filter 33. The first filter 31 uses the output signal of the OR circuit 29 as an input signal VA_IN, and when the duration of the Hi level of the input signal VA_IN reaches a predetermined first filter time ta, Hi indicating that a power supply abnormality has occurred. The level signal is output to the controller 19h. The second filter 32 uses the output signal of the switch terminal voltage detection circuit 27 as an input signal VB_IN, and when the duration of the Hi level of the input signal VB_IN reaches a predetermined second filter time tb, the Hi level indicating a power supply abnormality is reached. The signal is output to the controller 19h. The third filter 33 uses the output signal of the AND circuit 30 as an input signal VC_IN, and when the duration of the Hi level of the input signal VC_IN reaches a predetermined third filter time ct, the third filter 33 controls the Hi level signal indicating a power supply abnormality. Output to 19h. The filter times ta, tb, and ct of the first filter 31, the second filter 32, and the third filter 33 are defined so as to satisfy the relationship of ta ≧ tb> tk.

When the controller 19h inputs a Hi level signal from any of the first filter 31 to the third filter 33, the power bus 5 and 8 are energized with an overcurrent, and / or the power bus 5 and 8 are energized. It is determined that a power supply abnormality has occurred, and a changeover switch off drive signal for turning off the changeover switches 11 and 12 is output to the drive circuit 13. In response to this, the drive circuit 13 outputs an off drive signal for turning off the changeover switches 11 and 12 to the control terminals of the changeover switches 11 and 12.

As described above, the energization control device 10 according to the present embodiment includes a current detection circuit 15 for detecting the current energized in the power buses 5 and 8, and a switch terminal voltage detection circuit 27 for detecting the terminal voltage V1 of the changeover switch. have. In this way, the current detection circuit 15 and the switch terminal voltage detection circuit 27 are separately provided, their mounting environments are different, and their detection methods are also different. Therefore, disturbances such as noise are generated in the power buses 5 and 8. When they are superimposed, the degree of influence on each can be different.

Here, as described above, the first filter 31 is determined by the current determination circuit 16 that the current detected by the current detection circuit 15 is at a level corresponding to the overcurrent when a power failure occurs. When the period reaches the first filter time ta, a Hi level signal indicating a power supply abnormality is output. Further, in the second filter 32, the period in which the terminal voltage V1 detected by the switch terminal voltage detection circuit 27 is at a level corresponding to an abnormal voltage drop when a power failure occurs is set in the second filter time tb. When it reaches, a Hi level signal indicating a power failure is output.

However, when only one of the determination result of the level corresponding to the overcurrent by the current determination circuit 16 and the detection result of the level corresponding to the abnormal voltage drop by the switch terminal voltage detection circuit 27 is obtained, It cannot be denied that the result may be the result of being affected by disturbances such as noise. Therefore, in the present embodiment, the first filter time ta of the first filter 31 and the second filter time tb of the second filter 32 are set to be longer than the third filter time ct of the third filter 33. .. As a result, the power supply abnormality is based on only one of the determination result of the level corresponding to the overcurrent by the current determination circuit 16 and the detection result of the level corresponding to the abnormal voltage drop by the switch terminal voltage detection circuit 27. It is possible to reduce the possibility of erroneous detection when detecting. On the other hand, when both the determination result of the level corresponding to the overcurrent by the current determination circuit 16 and the detection result of the level corresponding to the abnormal voltage drop by the switch terminal voltage detection circuit 27 are obtained at the same time. Is not the effect of disturbance such as noise, but it is highly possible that an abnormality such as a power failure actually occurred. Therefore, in the present embodiment, both the determination result of the level corresponding to the overcurrent by the current determination circuit 16 and the detection result of the level corresponding to the abnormal voltage drop by the switch terminal voltage detection circuit 27 can be obtained at the same time. If this is the case, the Hi-level input signal VC_IN is configured to be input to the third filter 33 via the AND circuit 30. As described above, the third filter time ct of the third filter 33 is set shorter than the first filter time ta of the first filter 31 and the second filter time tb of the second filter 32. Therefore, by providing the third filter 33, it is possible to detect the power supply abnormality in a shorter time.

Here, in the energization control device 10 according to the present embodiment, the current detection circuit 15 and the switch terminal voltage detection circuit 27 are provided, and the first filter 31 and the second filter 32 have a power supply abnormality based on the respective abnormality detection signals. The reason for detecting the above will be described with reference to FIGS. 27 and 28. FIG. 27A conceptually shows the ground fault current flowing through the first power bus 5 and the changeover switches 11 and 12 when the second power bus 8 in the vicinity of the sub power supply 6 has a ground fault. .. In this case, as shown in FIG. 27B, the time until the terminal voltage V1 of the changeover switches 11 and 12 becomes lower than the threshold voltage Vth3 mainly due to the influence of the wiring impedances L1 and L2 of the power buses 5 and 8. Is longer than the time until the voltage signal V23 corresponding to the magnitude of the current flowing through the shunt resistor 14 exceeds the threshold voltage Vth1. On the other hand, FIG. 28A conceptualizes the ground fault current flowing through the first power bus 5 and the changeover switches 11 and 12 when the second power bus 8 in the vicinity of the switch terminal voltage detection circuit 27 has a ground fault. Is shown. In this case, as shown in FIG. 28B, the terminal voltage V1 of the changeover switches 11 and 12 immediately drops, so that the time until the terminal voltage V1 drops below the threshold voltage Vth3 flows through the shunt resistor 14. The voltage signal V23 corresponding to the magnitude of the current becomes shorter than the time until the threshold voltage Vth1 is exceeded. In this way, the detection time (detection sensitivity) of the power supply abnormality differs depending on the location of the ground fault depending on whether it is based on current detection or voltage detection. Therefore, based on the abnormality detection signals of the current detection circuit 15 and the switch terminal voltage detection circuit 27, the first filter 31 and the second filter 32 are configured to detect the power supply abnormality, so that the ground fault location can be determined. It is possible to detect power supply abnormalities with high sensitivity.

Next, an example of the processing flow executed by the energization control device 10 in order to detect a power supply abnormality will be described with reference to the flowchart of FIG.

First, in step S500, the current determination circuit 16 determines whether or not the voltage signal V23 exceeds the threshold voltage Vth1. If it is determined in step S500 that the voltage signal V23 exceeds the threshold voltage Vth1, the process proceeds to step S510. On the other hand, if it is determined in step S500 that the voltage signal V23 does not exceed the threshold voltage Vth1, the process proceeds to step S580.

In step S510, in the switch terminal voltage detection circuit 27, it is determined whether or not the terminal voltage V1 of the changeover switches 11 and 12 is lower than the threshold voltage Vth3. If it is determined in step S510 that the terminal voltage V1 is lower than the threshold voltage Vth3, the process proceeds to step S520. On the other hand, if it is determined in step S510 that the terminal voltage V1 is not lower than the threshold voltage Vth3, the process proceeds to step S560.

In step S520, in the third filter 33, it is determined whether or not the input signal VC_IN is at the Hi level continuously for the third filter time ct. In step S520, when it is determined that the input signal VC_IN is at the Hi level continuously for the third filter time ct, the process proceeds to step S530 to determine that the power supply is abnormal, and the third filter 33 outputs the power supply abnormality signal to the controller 19h. do. On the other hand, if it is determined in step S520 that the input signal VC_IN is not at the Hi level continuously for the third filter time ct, the process proceeds to step S540, and in the second filter 32, the input signal VB_IN is the second filter time tb. It is continuously determined whether or not the Hi level is reached. In step S540, when it is determined that the input signal VB_IN is at the Hi level continuously for the second filter time tb, the process proceeds to step S550 to determine that the power supply is abnormal, and the second filter 32 outputs the power supply abnormality signal to the controller 19h. do. On the other hand, if it is determined in step S540 that the input signal VB_IN is not at the Hi level continuously for the second filter time tb, the process returns to the process of step S500.

In step S560, which is executed when it is determined in step S510 that the terminal voltage V1 is not lower than the threshold voltage Vth3, the input signal VA_IN is continuously at the Hi level in the first filter 31 for the first filter time ta. Whether or not it is determined. In step S560, when it is determined that the input signal VA_IN is at the Hi level continuously for the first filter time ta, the process proceeds to step S570 to determine that the power supply is abnormal, and the first filter 31 outputs the power supply abnormality signal to the controller 19h. do. On the other hand, if it is determined in step S560 that the input signal VA_IN is not at the Hi level continuously for the first filter time ta, the process returns to the process of step S500.

In step S580, which is executed when it is determined in step S500 that the voltage signal V23 does not exceed the threshold voltage Vth1, the terminal voltage V1 of the changeover switches 11 and 12 is more than the threshold voltage Vth3 in the switch terminal voltage detection circuit 27. It is determined whether or not the voltage has decreased. If it is determined in step S580 that the terminal voltage V1 is lower than the threshold voltage Vth3, the process proceeds to step S590. On the other hand, if it is determined in step S580 that the terminal voltage V1 is not lower than the threshold voltage Vth3, the process returns to the process of step S500. In step S590, in the second filter 32, it is determined whether or not the input signal VB_IN is continuously at the Hi level for the second filter time tb. In step S590, when it is determined that the input signal VB_IN is at the Hi level continuously for the second filter time tb, the process proceeds to step S600 to determine that the power supply is abnormal, and the second filter 32 outputs the power supply abnormality signal to the controller 19h. do. On the other hand, if it is determined in step S590 that the input signal VB_IN is not at the Hi level continuously for the second filter time tb, the process returns to step S500.

The process in the current determination circuit 16, the switch terminal voltage detection circuit 27, and the filter circuit 28 described above can also be executed by the controller 19h.

(8th Embodiment)
Next, the energization control device according to the eighth embodiment of the present invention will be described with reference to FIGS. 30 and 31.

FIG. 30 is a configuration diagram showing an example of the configuration of the energization control device 10 according to the present embodiment. The energization control device 10 according to the present embodiment includes changeover switches 11 and 12, drive circuit 13, shunt resistance 14, current detection circuit 15, current determination circuit 16, first voltage detection circuit 27, second voltage detection circuit 35, and filter. It includes a circuit 28i and a controller 19i. Among them, the circuit components and each electric circuit excluding the controller 19i, the filter circuit 28i, and the second voltage detection circuit 35 are configured in the same manner as in the seventh embodiment. That is, the first voltage detection circuit 27 of the present embodiment has the same configuration as the switch terminal voltage detection circuit 27 of the seventh embodiment.

The second voltage detection circuit 35 is also configured in substantially the same manner as the first voltage detection circuit 27, and detects whether or not the terminal voltage V1 of the changeover switches 11 and 12 is larger than the threshold voltage Vth4. However, the threshold voltage Vth4 of the second voltage detection circuit 35 is set higher than the threshold voltage Vth3 of the first voltage detection circuit 27. For example, the threshold voltage Vth4 can be set to 8 (V), and the threshold voltage Vth3 can be set to 3 (V). In this way, by setting the threshold voltage Vth4 of the second voltage detection circuit 35 higher than the threshold voltage Vth3 of the first voltage detection circuit 27, the second voltage detection circuit 35 can detect a sign of a power supply abnormality. , The power supply abnormality can be detected by the first voltage detection circuit 27. In other words, even if the terminal voltage V1 is lower than the threshold voltage Vth4 of the second voltage detection circuit 35, it cannot be concluded that the power supply is abnormal, but it can be regarded as suggesting the possibility of causing the power supply abnormality. .. On the other hand, when the terminal voltage V1 is lower than the threshold voltage Vth3 of the first voltage detection circuit 27, it is a level corresponding to the potential drop when a power failure occurs, and can be regarded as a power supply abnormality. The second voltage detection circuit 35 outputs a Hi level signal when the terminal voltage V1 drops below the threshold voltage Vth4. The output signal of the second voltage detection circuit 35 is given to the selector circuit 34.

The selector circuit 34 inputs signals from the first filter 31 and the third filter 33. The first filter 31 and the third filter 33 have the same functions as the first filter 31 and the third filter 33 of the filter circuit 28 of the seventh embodiment. That is, when the duration of the Hi level of the input signal VAC_IN reaches the predetermined first filter time ta, the first filter 31 outputs a Hi level signal indicating that a power supply abnormality has occurred. When the duration of the Hi level of the input signal VAC_IN reaches the predetermined third filter time ct, the third filter 33 outputs a Hi level signal indicating that a power supply abnormality has occurred. The first filter time ta is set longer than the third filter time ct.

Then, the selector circuit 34 switches whether to output the signal from the first filter 31 or the signal from the third filter 33 to the controller 19i according to the level of the output signal from the second voltage detection circuit 35. Specifically, when the level of the output signal of the second voltage detection circuit 35 is Lo level, the selector circuit 34 outputs the signal of the first filter 31 to the controller 19i. On the other hand, when the level of the output signal of the second voltage detection circuit 35 is Hi level, the selector circuit 34 outputs the signal of the third filter 33 to the controller 19i. Therefore, when it is determined in the current determination circuit 16 that the voltage signal V23 exceeds the threshold voltage Vth1 and a sign of a power supply abnormality is detected in the second voltage detection circuit 35, the signal from the third filter 33 is detected. It is determined whether or not a power supply abnormality has occurred based on. Therefore, in a situation where there is a high possibility that a power supply abnormality has occurred, the power supply abnormality can be detected in a shorter time as in the seventh embodiment. On the other hand, if it is determined that the voltage signal V23 exceeds the threshold voltage Vth1, but no sign of power supply abnormality is detected by the second voltage detection circuit 35, a power supply abnormality occurs based on the signal from the first filter 31. Determine if it is present. Therefore, it is possible to reduce the possibility of erroneous detection of a power supply abnormality in a situation where it is uncertain whether a power supply abnormality has occurred.

Further, in the present embodiment, the selector circuit 34 is configured to switch which input signal is output to the controller 19i according to the level of the output signal of the second voltage detection circuit 35 that detects the sign of the power supply abnormality. ing. Therefore, it is possible to further shorten the time from the occurrence of the power supply abnormality to the detection of the power supply abnormality.

However, the selector circuit 34 may be configured to switch which input signal is output according to the level of the output signal of the first voltage detection circuit 27 instead of the output signal of the second voltage detection circuit 35. good. Further, the output signal of the first voltage detection circuit 27 is input to the second filter 32 and the third filter 33, and the selector circuit 34 inputs the signal from the second filter 32 and the signal from the third filter 33. The selector circuit 34 may be configured to switch which input signal is output according to the output signal from the current determination circuit 16 (output signal of the OR circuit 29).

Next, an example of the processing flow executed in the energization control device 10 of the present embodiment in order to detect a power supply abnormality will be described with reference to the flowchart of FIG.

First, in step S700, the current determination circuit 16 determines whether or not the voltage signal V23 exceeds the threshold voltage Vth1. If it is determined in step S700 that the voltage signal V23 exceeds the threshold voltage Vth1, the process proceeds to step S710. On the other hand, if it is determined in step S700 that the voltage signal V23 does not exceed the threshold voltage Vth1, the process proceeds to step S840.

In step S710, in the first voltage detection circuit 27, it is determined whether or not the terminal voltage V1 of the changeover switches 11 and 12 is lower than the threshold voltage Vth3. If it is determined in step S710 that the terminal voltage V1 is lower than the threshold voltage Vth3, the process proceeds to step S720. On the other hand, if it is determined in step S710 that the terminal voltage V1 is not lower than the threshold voltage Vth3, the process proceeds to step S790.

In step S720, in the second filter 32, it is determined whether or not the input signal VB_IN is continuously at the Hi level for the second filter time tb. If it is determined in step S720 that the input signal VB_IN is at the Hi level continuously for the second filter time tb, the process proceeds to step S730 to determine that the power supply is abnormal, and the second filter 32 outputs the power supply abnormality signal to the controller 19i. do. On the other hand, if it is determined in step S720 that the input signal VB_IN is not at the Hi level continuously for the second filter time tb, the process proceeds to step S740, and in the third filter 33, the input signal VAC_IN is the third filter time tc. It is continuously determined whether or not the Hi level is reached. When it is determined in step S740 that the input signal VAC_IN is continuously at the Hi level for the third filter time ct, the process proceeds to step S750, and the terminal voltage V1 drops below the threshold voltage Vth4 in the second voltage detection circuit 35. Whether or not it is determined. If it is determined in step S750 that the terminal voltage V1 is lower than the threshold voltage Vth4, the process proceeds to step S760 to determine that the power supply is abnormal, and the third filter 33 outputs a power supply abnormality signal to the controller 19i. On the other hand, if it is determined in step S750 that the terminal voltage V1 is not lower than the threshold voltage Vth4, the process proceeds to step S770. In step S770, the first filter 31 determines whether or not the input signal VAC_IN is at the Hi level continuously for the first filter time ta. In step S770, when it is determined that the input signal VAC_IN is at the Hi level continuously for the first filter time ta, the process proceeds to step S780 to determine that the power supply is abnormal, and the first filter 31 outputs the power supply abnormality signal to the controller 19i. do. On the other hand, if it is determined in step S770 that the input signal VAC_IN is not at the Hi level continuously for the first filter time ta, the process returns to the process of step S700.

In step S790, which is executed when it is determined in step S710 that the terminal voltage V1 is not lower than the threshold voltage Vth3, in the third filter 33, the input signal VAC_IN is continuously at the Hi level for the third filter time ct. Whether or not it is determined. If it is determined in step S790 that the input signal VAC_IN is continuously at the Hi level for the third filter time ct, the process proceeds to step S800. On the other hand, when it is determined that the input signal VAC_IN is not at the Hi level continuously for the third filter time ct, the process returns to the process of step S700. In step S800, in the second voltage detection circuit 35, it is determined whether or not the terminal voltage V1 is lower than the threshold voltage Vth4. If it is determined in step S800 that the terminal voltage V1 is lower than the threshold voltage Vth4, the process proceeds to step S810 to determine that the power supply is abnormal, and the third filter 33 outputs a power supply abnormality signal to the controller 19i. On the other hand, if it is determined in step S800 that the terminal voltage V1 is not lower than the threshold voltage Vth4, the process proceeds to step S820. In step S820, the first filter 31 determines whether or not the input signal VAC_IN is at the Hi level continuously for the first filter time ta. In step S820, when it is determined that the input signal VAC_IN is at the Hi level continuously for the first filter time ta, the process proceeds to step S830 to determine that the power supply is abnormal, and the first filter 31 outputs the power supply abnormality signal to the controller 19i. do. On the other hand, if it is determined in step S820 that the input signal VAC_IN is not at the Hi level continuously for the first filter time ta, the process returns to the process of step S700.

In step S840, which is executed when it is determined in step S700 that the voltage signal V23 does not exceed the threshold voltage Vth1, the terminal voltage V1 of the changeover switches 11 and 12 is set from the threshold voltage Vth3 in the first voltage detection circuit 27. It is determined whether or not the voltage has decreased. If it is determined in step S840 that the terminal voltage V1 is lower than the threshold voltage Vth3, the process proceeds to step S850. On the other hand, if it is determined in step S840 that the terminal voltage V1 is not lower than the threshold voltage Vth3, the process returns to step S700. In step S850, in the second filter 32, it is determined whether or not the input signal VB_IN is continuously at the Hi level for the second filter time tb. In step S850, when it is determined that the input signal VB_IN is at the Hi level continuously for the second filter time tb, the process proceeds to step S860 to determine that the power supply is abnormal, and the second filter 32 outputs the power supply abnormality signal to the controller 19h. do. On the other hand, if it is determined in step S850 that the input signal VB_IN is not at the Hi level continuously for the second filter time tb, the process returns to step S700.

The controller 19h can also execute each of the processes in the current determination circuit 16, the first voltage detection circuit 27, the filter circuit 28i, and the second voltage detection circuit 35 described above.

(9th Embodiment)
Next, the energization control device according to the ninth embodiment of the present invention will be described with reference to FIGS. 32 and 33.

FIG. 32 is a configuration diagram showing the configuration of the energization control device 10 according to the present embodiment. The energization control device 10 according to the present embodiment includes changeover switches 11 and 12, drive circuit 13, shunt resistance 14, current detection circuit 15, current determination circuit 16j, first voltage detection circuit 27, second voltage detection circuit 35, and filter. It includes a circuit 28j and a controller 19j. Of these, the circuit components and each electric circuit excluding the current determination circuit 16j, the filter circuit 28j, and the controller 19j are configured in the same manner as in the eighth embodiment.

The current determination circuit 16j is configured to be able to switch the threshold voltage Vth1 to be compared with the voltage signal V23 according to the level of the output signal of the second voltage detection circuit 35. For example, as shown in FIG. 32, when the threshold voltage Vth1 is set by dividing the power supply voltage Vcc by a series circuit of resistors, the resistors are connected in parallel with the resistance on the ground side and connected in parallel. Connect the changeover switch in series with the resistor. Then, the changeover switch is turned on when the level of the output signal of the second voltage detection circuit 35 is Hi level, and the changeover switch is turned off when the level of the output signal of the second voltage detection circuit 35 is Lo level. It is configured as follows. With such a configuration, when a sign of a power supply abnormality is detected by the second voltage detection circuit 35, the threshold voltage Vth1 becomes small, and an overcurrent is energized to the power buses 5 and 8 in the comparator 16a of the current determination circuit 16j. (That is, the detection sensitivity of the overcurrent abnormality is increased). As a result, when a power supply abnormality occurs, the level of the input signal VA_IN of the first filter 31 becomes the Hi level at an early timing, so that the time until the power supply abnormality is detected can be shortened.

The configuration for switching the threshold voltage Vth1 of the current determination circuit 16j according to the level of the output signal of the second voltage detection circuit 35 is not limited to the configuration shown in FIG. 32, and other configurations may be adopted. .. Further, in FIG. 32, the comparator 16b for determining the magnitude of the negative current in the current determination circuit 16j is omitted in order to avoid complicating the figure. The threshold voltage Vth1 ^(-) of the comparator 16b for determining the magnitude of this negative current is an absolute value for determining overcurrent when the level of the output signal of the second voltage detection circuit 35 reaches the Hi level. Can be switched to an increased value to reduce the size of. Then, the output of the comparator 16b is input to the other input terminal of the OR circuit 29 of the filter circuit 28j. Further, the threshold voltage Vth1 of the current determination circuit 16j may be switched according to the level of the output signal of the first voltage detection circuit 27 instead of the output signal of the second voltage detection circuit 35. Further, instead of switching the threshold voltage Vth1 of the current determination circuit 16j, the threshold voltage Vth3 of the first voltage detection circuit 27 may be switched according to the output signal of the current determination circuit 16j (output signal of the OR circuit 29). .. Specifically, when the output signal of the current determination circuit 16 (the output signal of the OR circuit 29) reaches the Hi level, the threshold voltage may be switched to a higher threshold voltage as compared with the case of the Lo level.

Next, an example of the processing flow executed in the energization control device 10 of the present embodiment in order to detect a power supply abnormality will be described with reference to the flowchart of FIG. 33.

First, in step S900, in the second voltage detection circuit 35, it is determined whether or not the terminal voltage V1 is lower than the threshold voltage Vth4. If it is determined in step S900 that the terminal voltage V1 is lower than the threshold voltage Vth4, the process proceeds to step S910, and the threshold changeover switch is turned on in the current determination circuit 16j. On the other hand, if it is determined in step S900 that the terminal voltage V1 is not lower than the threshold voltage Vth4, the process proceeds to step S980, and the threshold changeover switch is turned off in the current determination circuit 16j.

In step S920, which is executed after the process of step S910, is the voltage signal V23 exceeding the threshold voltage Vth1 using the reduced threshold voltage Vth1 by turning on the threshold changeover switch in the current determination circuit 16j? Whether or not it is determined. If it is determined in step S920 that the voltage signal V23 exceeds the threshold voltage Vth1, the process proceeds to step S930. On the other hand, if it is determined in step S920 that the voltage signal V23 does not exceed the threshold voltage Vth1, the process proceeds to step S950.

In step S930, in the first filter 31, it is determined whether or not the input signal VA_IN is at the Hi level continuously for the first filter time ta. In step S930, when it is determined that the input signal VA_IN is at the Hi level continuously for the first filter time ta, the process proceeds to step S940 to determine that the power supply is abnormal, and the first filter 31 outputs the power supply abnormality signal to the controller 19j. do. On the other hand, if it is determined in step S930 that the input signal VA_IN is not at the Hi level continuously for the first filter time ta, the process returns to the process of step S900.

In step S950, in the first voltage detection circuit 27, it is determined whether or not the terminal voltage V1 of the changeover switches 11 and 12 is lower than the threshold voltage Vth3. If it is determined in step S950 that the terminal voltage V1 is lower than the threshold voltage Vth3, the process proceeds to step S960. On the other hand, if it is determined in step S950 that the terminal voltage V1 is not lower than the threshold voltage Vth3, the process returns to step S900. In step S960, in the second filter 32, it is determined whether or not the input signal VB_IN is continuously at the Hi level for the second filter time tb. In step S960, when it is determined that the input signal VB_IN is at the Hi level continuously for the second filter time tb, the process proceeds to step S970 to determine that the power supply is abnormal, and the second filter 32 outputs the power supply abnormality signal to the controller 19j. do. On the other hand, if it is determined in step S960 that the input signal VB_IN is not at the Hi level continuously for the second filter time tb, the process returns to step S900.

In step S990 executed after the process of step S980, is the voltage signal V23 exceeding the threshold voltage Vth1 by using the increased threshold voltage Vth1 by turning off the threshold change switch in the current determination circuit 16j? Whether or not it is determined. If it is determined in step S990 that the voltage signal V23 exceeds the threshold voltage Vth1, the process proceeds to step S1000. On the other hand, if it is determined in step S990 that the voltage signal V23 does not exceed the threshold voltage Vth1, the process proceeds to step S1020.

In step S1000, in the first filter 31, it is determined whether or not the input signal VA_IN is at the Hi level continuously for the first filter time ta. In step S1000, when it is determined that the input signal VA_IN is at the Hi level continuously for the first filter time ta, the process proceeds to step S1010 to determine that the power supply is abnormal, and the first filter 31 outputs the power supply abnormality signal to the controller 19j. do. On the other hand, if it is determined in step S1010 that the input signal VA_IN is not at the Hi level continuously for the first filter time ta, the process returns to the process of step S900.

In step S1020, in the first voltage detection circuit 27, it is determined whether or not the terminal voltage V1 of the changeover switches 11 and 12 is lower than the threshold voltage Vth3. If it is determined in step S1020 that the terminal voltage V1 is lower than the threshold voltage Vth3, the process proceeds to step S1030. On the other hand, if it is determined in step S1020 that the terminal voltage V1 is not lower than the threshold voltage Vth3, the process returns to the process of step S900. In step S1030, in the second filter 32, it is determined whether or not the input signal VB_IN is continuously at the Hi level for the second filter time tb. In step S1030, when it is determined that the input signal VB_IN is at the Hi level continuously for the second filter time tb, the process proceeds to step S1040 to determine that the power supply is abnormal, and the second filter 32 outputs the power supply abnormality signal to the controller 19j. do. On the other hand, if it is determined in step S1030 that the input signal VB_IN is not at the Hi level continuously for the second filter time tb, the process returns to step S900.

The controller 19h can also execute each of the processes in the current determination circuit 16j, the first voltage detection circuit 27, the filter circuit 28j, and the second voltage detection circuit 35 described above.

(10th Embodiment)
Next, the energization control device 10 according to the tenth embodiment of the present invention will be described with reference to FIGS. 34 and 35. FIG. 34 is a configuration diagram showing an example of the configuration of the energization control device according to the embodiment. Further, FIG. 35 is a flowchart showing an example of a processing flow for detecting a power supply abnormality, which is executed in the energization control device according to the present embodiment.

The energization control device 10 according to the seventh embodiment described above has a current detection circuit 15 for detecting the current energized in the power buses 5 and 8, and a switch terminal voltage detection circuit for detecting the terminal voltage V1 of the changeover switches 11 and 12. 27 is provided, and the abnormality determination conditions for determining the power supply abnormality are different depending on the detection results of the respective detection circuits 15 and 27. On the other hand, as shown in FIG. 34, the energization control device 10 according to the present embodiment includes a current detection circuit 15 and a sense current detection circuit 36, depending on the detection results of the respective detection circuits 15 and 27, respectively. , The abnormality determination condition for determining the power supply abnormality is different. That is, the energization control device 10 according to the present embodiment replaces the switch terminal voltage detection circuit 27 of the energization control device 10 according to the seventh embodiment, and is a sense current for detecting a current abnormality (overcurrent) of the power bus. The detection circuit 36 is provided.

As described above, the changeover switches 11 and 12 are composed of semiconductor switching elements such as MOSFETs. In the present embodiment, the semiconductor switching element is configured to include a main region and a sense region. The size of the sense region and the main region is determined so that a predetermined ratio of the current flowing through the main region flows in the sense region.

The sense current detection circuit 36 detects the current flowing through the sense region of the semiconductor switching element constituting the changeover switch 11. As described above, the two detection circuits for detecting the power abnormality in the power buses 5 and 8 may both detect the current flowing through the power buses 5 and 8. Although not shown, the sense current detection circuit 36 includes a detection circuit for detecting a positive current and a detection circuit for detecting a negative current. Then, when either the positive current or the negative current exceeds the threshold voltage Vth5, the sense current detection circuit 36 outputs a Hi level signal indicating that the level corresponds to the overcurrent.

The filter circuit 28k of the present embodiment has the same configuration as the filter circuit 28 of the seventh embodiment. Therefore, when only one of the determination result of the level corresponding to the overcurrent by the current determination circuit 16 and the detection result of the level corresponding to the overcurrent by the sense current detection circuit 36 is obtained, it is relatively relative. Using the long set first filter time ta or second filter time tb, it is determined whether or not the overcurrent is energized. On the other hand, when both the determination result of the level corresponding to the overcurrent by the current determination circuit 16 and the detection result of the level corresponding to the overcurrent by the sense current detection circuit 36 are obtained at the same time, they are relative. It is determined whether or not the overcurrent is energized by using the third filter time ct which is set to be short.

Next, an example of the processing flow executed by the energization control device 10 in order to detect a power supply abnormality will be described with reference to the flowchart of FIG. 35.

First, in step S1100, the current determination circuit 16 determines whether or not the voltage signal V23 exceeds the threshold voltage Vth1. If it is determined in step S1100 that the voltage signal V23 exceeds the threshold voltage Vth1, the process proceeds to step S1110. On the other hand, if it is determined in step S1100 that the voltage signal V23 does not exceed the threshold voltage Vth1, the process proceeds to step S1180.

In step S1110, in the sense current detection circuit 36, it is determined whether or not the voltage signal VM2 corresponding to the magnitude of the sense current V2S exceeds the threshold voltage Vth5. If it is determined in step S1110 that the voltage signal VM2 exceeds the threshold voltage Vth5, the process proceeds to step S1120. On the other hand, if it is determined in step S1110 that the voltage signal VM2 does not exceed the threshold voltage Vth5, the process proceeds to step S1160.

In step S1120, in the third filter 33, it is determined whether or not the input signal VC_IN is at the Hi level continuously for the third filter time ct. In step S1120, when it is determined that the input signal VC_IN is at the Hi level continuously for the third filter time ct, the process proceeds to step S1130 to determine that the power supply is abnormal, and the third filter 33 outputs the power supply abnormality signal to the controller 19k. do. On the other hand, if it is determined in step S1120 that the input signal VC_IN is not at the Hi level continuously for the third filter time ct, the process proceeds to step S1140, and in the second filter 32, the input signal VB_IN is the second filter time tb. It is continuously determined whether or not the Hi level is reached. When it is determined in step S1140 that the input signal VB_IN is at the Hi level continuously for the second filter time tb, the process proceeds to step S1150 to determine that the power supply is abnormal, and the second filter 32 outputs the power supply abnormality signal to the controller 19k. do. On the other hand, if it is determined in step S1140 that the input signal VB_IN is not at the Hi level continuously for the second filter time tb, the process returns to the process of step S1100.

In step S1160, which is executed when it is determined in step S1110 that the voltage signal VM2 does not exceed the threshold voltage Vth5, is the input signal VA_IN continuously at the Hi level in the first filter 31 for the first filter time ta? Whether or not it is determined. In step S1160, when it is determined that the input signal VA_IN is at the Hi level continuously for the first filter time ta, the process proceeds to step S1170 to determine that the power supply is abnormal, and the first filter 31 outputs the power supply abnormality signal to the controller 19k. do. On the other hand, if it is determined in step S1160 that the input signal VA_IN is not at the Hi level continuously for the first filter time ta, the process returns to the process of step S1100.

In step S1180 executed when it is determined in step S1100 that the voltage signal V23 does not exceed the threshold voltage Vth1, it is determined in the sense current detection circuit 36 whether or not the voltage signal VM2 exceeds the threshold voltage Vth5. .. If it is determined in step S1180 that the voltage signal VM2 exceeds the threshold voltage Vth5, the process proceeds to step S1190. On the other hand, if it is determined in step S1180 that the voltage signal VM2 does not exceed the threshold voltage Vth5, the process returns to the process of step S1100. In step S1190, in the second filter 32, it is determined whether or not the input signal VB_IN is continuously at the Hi level for the second filter time tb. In step S1190, when it is determined that the input signal VB_IN is at the Hi level continuously for the second filter time tb, the process proceeds to step S1200 to determine that the power supply is abnormal, and the second filter 32 outputs the power supply abnormality signal to the controller 19k. do. On the other hand, if it is determined in step S1190 that the input signal VB_IN is not at the Hi level continuously for the second filter time tb, the process returns to the process of step S1100.

The process in the current determination circuit 16, the sense current detection circuit, and the filter circuit 28 described above can also be executed by the controller 19h.

(11th Embodiment)
Next, the energization control device according to the eleventh embodiment of the present invention will be described with reference to FIG. 36. FIG. 36 is a configuration diagram showing an example of the configuration of the energization control device 10 according to the present embodiment. The energization control device 10 according to the present embodiment includes changeover switches 11 and 12, drive circuit 13, shunt resistance 14, current detection circuit 15, current determination circuit 16, switch terminal voltage detection circuit 27, sense current detection circuit 36, and filter circuit. It is equipped with 28 liters and a controller 19 liters. As described above, the energization control device 10 according to the present embodiment includes any of the current determination circuit 16, the switch terminal voltage detection circuit 27, and the sense current detection circuit 36.

The filter circuit 28l has an AND circuit 37 having the output signal of the OR circuit 29 as one input and the output signal from the switch terminal voltage detection circuit 27 as the other input, and the OR circuit 29 having the output signal of the OR circuit 29 as one input. It has an AND circuit 38 in which the output signal from the sense current detection circuit 36 is used as the other input. Further, the filter circuit 28l also has an AND circuit 39 in which the output signal of the AND circuit 37 is used as one input and the output signal of the AND circuit 38 is used as the other input. Further, the filter circuit 28l is provided with a fourth filter 40, a fifth filter 41, and a sixth filter 42. The fourth filter 40 uses the output signal of the AND circuit 37 as an input signal VD_IN, and when the duration of the Hi level of the input signal VD_IN reaches a predetermined fourth filter time td, Hi indicating that a power supply abnormality has occurred. The level signal is output to the controller 19l. The fifth filter 41 uses the output signal of the AND circuit 38 as an input signal VE_IN, and when the duration of the Hi level of the input signal VE_IN reaches a predetermined fifth filter time te, the fifth filter 41 controls the Hi level signal indicating a power supply abnormality. Output to 19 liters. The sixth filter 42 uses the output signal of the AND circuit 39 as an input signal VF_IN, and when the duration of the Hi level of the input signal VF_IN reaches a predetermined sixth filter time tf, the sixth filter 42 controls the Hi level signal indicating a power supply abnormality. Output to 19 liters.

The filter times td, te, and tf of the fourth filter 40, the fifth filter 41, and the sixth filter 42 are set so as to satisfy the relationship of tf <td, tf <te, respectively. Further, the fourth filter time td in the present embodiment corresponds to the third filter time tc in the seventh embodiment. Further, the fifth filter time te in the maintenance embodiment corresponds to the third filter time ct in the tenth embodiment. The magnitude relationship between the fourth filter time td and the fifth filter time te is arbitrary.

When the controller 19h inputs a Hi level signal from any of the fourth filter 40 to the sixth filter 42, the power supply error in which the overcurrent is energized in the power buses 5 and 8 and / or the power bus 5 and 8 It is determined that a power supply abnormality has occurred, and a changeover switch off drive signal for turning off the changeover switches 11 and 12 is output to the drive circuit 13.

As described above, the energization control device 10 according to the present embodiment detects the current or voltage of the power buses 5 and 8 by the three detection circuits, and the larger the number of detection circuits whose detection results simultaneously indicate a power supply abnormality, the more. The abnormality determination conditions are different so that it can be determined that a power supply abnormality has occurred in the power buses 5 and 8 in a shorter time. Therefore, the more surely the power supply abnormality can be considered to have occurred, the shorter the time until the power supply abnormality is detected can be shortened.

In the energization control device 10 shown in FIG. 36, the output signal of the current determination circuit 16, the output signal of the switch terminal voltage detection circuit 27, and the output signal of the sense current detection circuit 36 are individually set to a predetermined filter time Hi level. A filter circuit may be added to determine whether or not the above is continued. Further, in FIG. 36, a combination signal of the output signal of the current determination circuit 16 and the output signal of the switch terminal voltage detection circuit 27 is input to the fourth filter 40, and the output signal of the current determination circuit 16 and the sense current detection circuit 36 are taken. An example of inputting a combination signal with the output signal of the above to the fifth filter 41 is shown. However, the combination of signals is arbitrary.

(12th Embodiment)
Next, the energization control device according to the twelfth embodiment of the present invention will be described with reference to FIGS. 37 and 38. FIG. 37 is a configuration diagram showing an example of the configuration of the energization control device 10 according to the present embodiment. The energization control device 10 according to the present embodiment includes changeover switches 11 and 12, drive circuit 13 m, shunt resistance 14, current detection circuit 15, current determination circuit 16, VM-V2 voltage detection circuit 43, and VM-V2 voltage determination. It includes a circuit 44, a filter circuit 28m, and a controller 19m. Of these, the circuit components and electric circuits excluding the drive circuit 13m, the VM-V2 voltage detection circuit 43, the VM-V2 voltage determination circuit 44, the filter circuit 28m, and the controller 19m are configured in the same manner as in the seventh embodiment. Will be done.

In the present embodiment, the controller 19m can instruct the drive circuit to turn on and off individually by the changeover switch 11 and the changeover switch 12. That is, the controller 19m can individually output the on / off drive signal for the changeover switch 11 and the on / off drive signal for the changeover switch 12 to the drive circuit 13m. When the Hi level signal is input from the comparator 16a of the current determination circuit 16 when the changeover switches 11 and 12 are both turned on, the controller 19m corresponds to an overcurrent in the positive direction of the power buses 5 and 8. It can be recognized that the level current is energized. In this case, the controller 19m outputs a drive signal for turning off the changeover switch, that is, the changeover switch 12 on the side where the current flows through the body diode even if it is cut off, to the drive circuit 13m. On the contrary, when the Hi level signal is input from the comparator 16b of the current determination circuit 16, the controller 19m can recognize that a current at a level corresponding to an overcurrent is energized in the negative direction. In this case, the controller 19m outputs a drive signal for turning off the changeover switch 11 to the drive circuit 13m. Note that FIG. 37 shows a state in which a current is flowing in the negative direction.

The drive circuit 13m turns on / off the changeover switches 11 and 12 according to the drive signal from the controller 19m. As shown in the example of FIG. 37, when the overcurrent is energized in the negative direction, the drive circuit 13m turns off the changeover switch 11 according to the instruction from the controller 19m. Then, the current flows only through the body diode of the changeover switch 11.

The voltage detection circuit 43 between VM and V2 is configured in the same manner as the current detection circuit 15. The VM-V2 voltage detection circuit 43 has a differential amplifier 43a, and detects the voltage signal V2M corresponding to the voltage difference between the voltage V2 across the changeover switch 11 and the VM as the magnitude of the current flowing through the changeover switch 11. And output. As shown in FIG. 37, a reference voltage Vref-c is input to the non-inverting input terminal of the differential amplifier 43a. As a result, the differential amplifier 43a outputs a voltage signal V2M higher than the reference voltage Vref-c by the amount corresponding to the voltage difference in which the voltage VM is higher than the voltage V2.

The VM-V2 voltage determination circuit 44 compares the voltage signal V2M output from the VM-V2 voltage detection circuit 43 with the threshold voltage Vth6, and when the voltage signal V2M is larger than the threshold voltage Vth6, the Hi level is reached. It has a comparator 44a that outputs a signal. The output signal of the voltage determination circuit 44 between VM and V2 is input to the AND circuit 45.

In addition to the output signal of the voltage determination circuit 44 between VM and V2, the output signal of the comparator 16b of the current determination circuit 16 is also input to the AND circuit 45. Further, the ON / OFF drive signal of the changeover switch 11 is also input to the AND circuit 45 from the controller 19m via the inverting terminal. The on / off drive signal of the changeover switch 11 from the controller 19 becomes the Hi level when instructing to turn on the changeover switch 11, and becomes the Lo level when instructing to turn off the changeover switch 11.

Therefore, when the controller 19m instructs to turn on the changeover switch 11, the output signal of the AND circuit 45 is always at the Lo level. On the other hand, when the controller 19m is instructing to turn off the changeover switch 11, the signal input via the inverting terminal becomes the Hi level, so that the AND circuit 45 determines the voltage between the current determination circuit 16 and the VM-V2. A signal corresponding to the level of the output signal of the circuit 44 can be output. That is, the controller 19m first captures only the determination result of the current determination circuit 16, and when the captured determination result indicates a power supply abnormality, the determination result of the current determination circuit 16 and the determination result of the VM-V2 voltage determination circuit. Change the abnormality judgment condition so as to capture and.

Then, the AND circuit 45 determines the level of the output signal of the comparator 16b of the current determination circuit 16 and the output of the voltage determination circuit 44 between VM and V2 when the signal input via the inverting terminal is at the Hi level. When both signal levels reach the Hi level, a Hi level signal is output. The signal output by the AND circuit 45 is the input signal VG_IN of the seventh filter 46. When this input signal VG_IN is Hi level continuously for the 7th filter time tg, the 7th filter 46 outputs a Hi level signal indicating that a power supply abnormality in which an overcurrent flows has occurred to the controller 19m. In this way, by performing the power supply abnormality determination based on the determination results of the two determination circuits 16 and 44, it is possible to reduce the possibility of erroneously detecting that the overcurrent is energized.

In FIG. 37, when the changeover switch 11 is turned off and a current is applied only to the body diode of the changeover switch 11, the voltage difference between the voltages across the changeover switch 11 is detected, and the voltage difference is corresponding to the voltage difference. Only the circuit configuration for determining whether or not the voltage signal exceeds a predetermined reference voltage is shown. However, the energization control device 10 according to the present embodiment detects the voltage difference between the voltages across the changeover switch 12 when the changeover switch 12 is turned off and the current is applied only to the body diode of the changeover switch 12. It also has a circuit configuration for determining whether or not the voltage signal corresponding to the voltage difference exceeds a predetermined reference voltage.

Next, an example of the processing flow executed by the energization control device 10 according to the present embodiment will be described with reference to the flowchart of FIG. 38.

First, in step S1300, in the current determination circuit 16, it is determined whether or not the voltage signal V23 corresponding to the voltage difference between the voltages across the shunt resistance 14 exceeds the threshold voltage Vth1. If it is determined in step S1300 that the voltage signal V23 exceeds the threshold voltage Vth1, the process proceeds to step S1310. In step S1310, the controller 19m determines the direction of the current energized in the power buses 5 and 8 based on which of the comparators 16a and 16b of the current determination circuit 16 outputs the Hi level signal. If it is determined in step S1310 that the direction of the current is negative, the process proceeds to step S1320, and the controller 19m outputs a drive signal instructing the changeover switch 11 to be turned off to the drive circuit 13m. On the other hand, if it is determined in step S1310 that the direction of the current is the positive direction, the process proceeds to step S1330, and the controller 19m outputs a drive signal instructing the changeover switch 12 to be turned off to the drive circuit 13m. The drive signal from the controller 19m is also input to the AND circuit 45 at the same time.

In step S1340, in the VM-V2 voltage determination circuit 44 (or the VM-V1 voltage determination circuit (not shown)), the voltage across the changeover switch 11 V2M (or the voltage across the changeover switch 12 V1M) is higher than the threshold voltage Vth6. Whether it is large or not is determined. Further, in step S1350, in the seventh filter 46, it is determined whether or not the period in which the voltage across V2M (or V1M) is larger than the threshold voltage Vth6 continues for the seventh filter time tg. If it is determined that the period in which the voltage across the ends V2M (or V1M) is larger than the threshold voltage Vth6 continues for the seventh filter time tg, the process proceeds to step S1360 to determine that the power supply is abnormal, and the seventh filter 46 is the controller 19m. Outputs a power supply error signal to. On the other hand, if it is determined in step S1350 that the period in which the voltage across V2M (or V1M) is larger than the threshold voltage Vth6 does not continue for the seventh filter time tg, the process returns to step S1300.

The controller 19m can also perform the processing in the current determination circuit 16, the VM-V2 voltage determination circuit, the AND circuit 45, the seventh filter 46, and the like described above.

Further, in the energization control device 10 according to the twelfth embodiment described above, when the determination result of the current determination circuit 16 as the first detection unit indicates a power supply abnormality, the second detection is performed together with the determination result of the current determination circuit 16. The determination result of the VM-V2 voltage determination circuit 44 (or the VM-V1 voltage determination circuit) as a unit is also configured to be input to the seventh filter 46. However, the first detection unit and the second detection unit are not limited to the examples described in the twelfth embodiment, and may be any combination including the switch terminal voltage detection circuit and the sense current detection circuit described in each of the above-described embodiments. Can be.

The controller described in the present disclosure and methods thereof may be realized by one or more dedicated computers having a processor and memory programmed to perform one or more functions embodied by a computer program. good. Alternatively, the controller and method thereof described in the present disclosure may be realized by one or more dedicated computers equipped with a processor configured by one or more dedicated hardware logic circuits. Alternatively, the controller and method thereof described in the present disclosure comprises a processor and memory programmed to perform one or more functions and a processor configured by combining one or more hardware logic circuits. It may be realized by one or more dedicated computers. Further, the computer program may be stored in a computer-readable non-transitional tangible recording medium as an instruction executed by the computer.

1: Main power supply, 2: Generator, 3: 1st component, 4: 2nd component, 5: 1st power bus, 6: Sub power supply, 7: 3rd component, 8: 2nd power bus, 9 : 4th component, 10: energization control device, 11: changeover switch, 12: changeover switch, 13: drive circuit, 14: shunt resistance, 15: current detection circuit, 16: current judgment circuit, 17: switch voltage detection circuit , 18: Voltage judgment circuit, 19: Controller, 20: Component controller, 21: Component actuator, 22: Controller, 23: ADAS controller, 24: Sensor group, 25: Shunt resistance, 26: Load current detection circuit, 27: Switch Terminal voltage detection circuit, 28: Filter circuit, 35: Second voltage detection circuit, 36: Sense current detection circuit, 43: VM-V2 voltage detection circuit, 44: VM-V2 voltage determination circuit, 111: Changeover switch, 112: Changeover switch, 113: Drive circuit, 114: Shunt resistance, 115: Current detection circuit

Claims (9)

It is applied to an energization system that energizes a current from a power source (1, 6) to a device (3, 4, 7) via a power bus (5, 8) to prevent an overcurrent from being energized in the power bus. It is an energization control device (10) and
The power source includes at least a first power source (1) and a second power source (6).
A changeover switch (11, 12) provided in the power bus connecting the first power source and the second power source and capable of switching between energization and interruption of current in the power bus.
A switch drive unit (13) that drives the changeover switch to switch between a conduction state and a cutoff state,
A current detection unit (14, 15) that detects the magnitude of the bidirectional current energized in the power bus, and
When it is determined that an overcurrent is energized in the power bus based on the magnitude of the current detected by the current detection unit, the overcurrent prevention control instructing the switch drive unit to drive the changeover switch to the cutoff state. With parts (16f, 19f),
The overcurrent prevention control unit determines whether or not the current energized in one direction of the power bus corresponds to the overcurrent, and determines whether or not the current energized in the other direction corresponds to the overcurrent. In addition, different judgment conditions are used ,
The first power supply has a larger power supply capacity and at least one of the power supply voltage than the second power supply.
The overcurrent prevention control unit energizes the power bus based on a determination condition that the time when the magnitude of the current detected by the current detection unit exceeds a predetermined threshold value exceeds a predetermined duration. It detects that
The overcurrent prevention control unit determines whether or not the current energized in the first direction from the first power source to the second power source in the power bus corresponds to the overcurrent as the predetermined duration. A second duration shorter than the first duration is used to determine whether or not the current energized in the second direction opposite to the first direction corresponds to an overcurrent by using the first duration for the determination. Energization control device that uses the duration of . The overcurrent prevention control unit uses the first threshold value as the predetermined threshold value for determining whether or not the current energized in the first direction corresponds to the overcurrent, and is opposite to the first direction. The energization control device according to claim 1, wherein a second threshold value smaller than the first threshold value is used for determining whether or not the current energized in the second direction corresponds to an overcurrent. The overcurrent prevention control unit is energized with a determination condition used for determining an overcurrent at least in the direction in which the large current is energized, in response to the condition that the large current is energized in the power bus is satisfied. The energization control device according to claim 1 or 2 , which switches to an erroneous detection prevention determination condition for avoiding erroneous detection of a current as an overcurrent. The overcurrent prevention control unit switches the determination condition to the false detection prevention determination condition by carrying out at least one of increasing the predetermined threshold value and increasing the predetermined duration. The energization control device according to claim 3 . When the overcurrent prevention control unit switches the determination condition to the false detection prevention determination condition by increasing the predetermined threshold value, even after the determination condition is switched to the false detection prevention determination condition, the first Whether the first threshold value used for determining whether or not the current energized in the direction corresponds to the overcurrent corresponds to the overcurrent in the current energized in the second direction opposite to the first direction. The energization control device according to claim 4 , which is set to be larger than the second threshold value used for determining whether or not. When the overcurrent prevention control unit switches the determination condition to the false detection prevention determination condition by lengthening the predetermined duration, even after the determination condition is switched to the false detection prevention determination condition, the first The first duration used to determine whether the current energized in one direction corresponds to an overcurrent, and the current energized in the second direction opposite to the first direction corresponds to the overcurrent. The energization control device according to claim 4 or 5 , which is set longer than the second duration used for determining whether or not to do so. The overcurrent prevention control unit cancels the switching to the false detection prevention determination condition after a predetermined period has elapsed since the large current was energized in the power bus.
Regarding the determination of whether or not the current energized in the first direction corresponds to the overcurrent, the predetermined first period until the switching to the false detection prevention determination condition is released is in the second direction. Claims 3 to 6 which are set longer than a predetermined second period until the switching to the false detection prevention determination condition is canceled with respect to the determination of whether or not the energized current corresponds to the overcurrent. The energization control device according to any one. The device (9) is energized with a current from the power bus connecting the first power source and the second power source.
The current detection unit includes a first current detection unit (15) that detects the direction and magnitude of a current flowing through the power bus between the first power supply and the device, and the second power supply. It includes a second current detection unit (115) that detects the direction and magnitude of the current flowing through the power bus between the device and the device.
Moreover,
A load current detection unit (26) that detects the magnitude of the current energized from the power bus to the device, and
The direction and magnitude of the current detected by the first current detection unit, the direction and magnitude of the current detected by the second current detection unit, and the magnitude of the current detected by the load current detection unit. The relationship of the current of each part determined according to the power supply state between the first power supply and the second power supply, and the power supply state from the first power supply and the second power supply to the device. The energization control device according to any one of claims 1 to 7 , further comprising a current abnormality determination unit (19 g) for determining a current abnormality when the relationship between orientation and size is different. The energization control device according to claim 8 , wherein the current abnormality determination unit instructs the switch drive unit to drive the changeover switch to the cutoff state when the current abnormality determination unit determines the current abnormality.

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