JP7095618B2 - Power supply - Google Patents

Description

The present disclosure relates to protection control in the event of an abnormality in a power supply device including a secondary battery.

The vehicle is provided with a power supply device including a secondary battery that supplies electric power to electric devices such as auxiliary machines. The power supply further includes a charging device that supplies power from a generator or other power source to the secondary battery to charge the secondary battery, and a relay that cuts off the connection between the secondary battery and the power supply destination. In such a power supply device, for example, a technique for operating a relay so that the secondary battery and the power supply destination are cut off when an abnormality occurs in the secondary battery is known.

For example, Japanese Patent Application Laid-Open No. 2014-017901 (Patent Document 1) describes according to the remaining capacity of the assembled battery when an abnormality occurs in the operation of the main control unit that stops the power supply from the assembled battery when the assembled battery is abnormal. Disclosed is a technique for setting a time during which evacuation travel is possible and continuing power supply from the assembled battery until the time during which evacuation travel is possible elapses.

Japanese Unexamined Patent Publication No. 2014-017901

However, if an abnormality occurs in the secondary battery that supplies power to electrical equipment such as auxiliary equipment, it is better to continue the power supply from the secondary battery depending on the degree of the abnormality. It may be desirable from the viewpoint of protecting the equipment, and it is required to appropriately set the execution timing of the protection control that cuts off the power supply from the secondary battery. Patent Document 1 sets the time during which the evacuation run is possible according to the remaining capacity of the assembled battery, and does not consider the above-mentioned problems at all.

The present disclosure has been made to solve the above-mentioned problems, and an object thereof is to provide a power supply device that executes protection control at an appropriate time when an abnormality occurs in the power supply device.

The power supply device according to a certain aspect of the present disclosure includes a secondary battery capable of supplying power to each of a plurality of electric devices operating as auxiliary equipment while the vehicle is in operation, and a plurality of power supplies during a part of the period during which the vehicle is in operation. A power supply device that can supply power to electrical equipment, a relay that can cut off the power supply from the secondary battery to each of multiple electrical equipment, and a detection device that detects an abnormal state of the secondary battery. And a control device that controls the relay using the detection result by the detection device, the state of the secondary battery, and the operating state of the power supply device. When the abnormal state of the secondary battery detected by the detection device is the first abnormal state, the control device has the first condition that the power supply device is operating and the second condition that the secondary battery is not in the discharged state. When the cutoff permission condition including the condition is satisfied, the relay is controlled so as to be in the cutoff state. When the abnormal state of the secondary battery is the first abnormal state, the control device continues to supply power from the secondary battery to each of the plurality of electric devices when the cutoff permission condition is not satisfied. When the abnormal state of the secondary battery is the second abnormal state in which the degree of abnormality is higher than that in the first abnormal state, the control device is in the shutoff state even if the cutoff permission condition is not satisfied. Control the relay so that.

By doing so, when the abnormal state of the secondary battery is the first abnormal state, the relay is controlled so as to be in the cutoff state when the cutoff permission condition is satisfied, so that even if the relay is cut off, after that. It is possible to protect the power supply device while suppressing the influence on the operation of the auxiliary equipment. Further, in the first abnormal state, when the cutoff permission condition is not satisfied, the power supply to the auxiliary machine is continued, so that the operation of the auxiliary machine can be continued. Further, in the case of the second abnormal state, the relay is controlled so as to be in the cutoff state even if the cutoff permission condition is not satisfied, so that the power supply device can be protected.

According to the present disclosure, it is possible to provide a power supply device that executes protection control at an appropriate time when an abnormality occurs in the power supply device.

It is a block diagram schematically showing an example of the whole structure of the vehicle equipped with the power supply device which concerns on this embodiment. It is a flowchart which shows an example of the process executed by the 1st monitoring unit. It is a figure for demonstrating the relay cutoff request flag set by the combination of the abnormal level of a low voltage battery and the state of a relay cutoff permission flag. It is a block diagram which shows an example of the whole structure of the vehicle equipped with the power supply device which concerns on the modification.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The same or corresponding parts in the drawings are designated by the same reference numerals and the description thereof will not be repeated.

FIG. 1 is a block diagram schematically showing an overall configuration of a vehicle 1 equipped with a power supply device according to the present embodiment. In the present embodiment, the vehicle 1 is, for example, a hybrid vehicle.

As shown in FIG. 1, the vehicle 1 includes a power supply device 2, an HV (Hybrid Vehicle) system 10, an EPS (Electric Power Steering) system 20, a brake system 30, a PCU (Power Control Unit) 50, and a motor. A generator (hereinafter referred to as MG) 52 is provided.

The HV system 10 is, for example, a plurality of electric devices (hereinafter, hereinafter, a plurality of electric devices) that operate as auxiliary machines by using the power of the low-voltage battery 80 when the vehicle 1 is hybrid-traveled among a plurality of electric devices that operate while the vehicle 1 is in operation. It may be described as low-pressure electrical equipment).

The low-pressure electric equipment includes, for example, a control device for controlling the PCU 50, a control device for controlling the DC / DC converter 40, a control device for controlling an engine (not shown), and an electric device mounted on the engine (not shown). For example, it includes auxiliary equipment such as a fuel injection device). The engine may be connected to a generator and used as a source of generated electric power, or may be connected to a drive wheel and used as a source of driving force.

The HV system 10 further includes a sensor that detects a current flowing through an auxiliary machine (for example, at least one of the various control devices and electric devices mounted on the engine described above). The sensor transmits a signal indicating the detected current to the first monitoring unit 200. Further, the HV system 10 transmits information regarding an operation command to the engine to the first monitoring unit 200. Further, the HV system 10 transmits information regarding an operation command to the DC / DC converter 40, which will be described later, to the first monitoring unit 200.

The EPS system 20 includes, for example, an electric device that operates as an auxiliary machine for electric power steering. The electric device that operates as an auxiliary machine of the electric power steering includes, for example, an actuator that generates an assist force that assists the steering force of the user, and a steering control device that controls the actuator. The steering control device adjusts the current applied to the actuator. The EPS system 20 further includes a sensor that detects a current flowing through an auxiliary machine (for example, an actuator). The sensor transmits a signal indicating the detected current to the first monitoring unit 200. Further, the EPS system 20 transmits information regarding an operation command to the actuator to the first monitoring unit 200.

The brake system 30 includes, for example, an electrical device that operates as an auxiliary machine of a braking device. The electrical equipment that operates as an auxiliary machine of the control device includes the electrical equipment that constitutes the antilock braking system, and includes, for example, an actuator that controls the braking force generated in the braking device and a brake control device that controls the actuator. The brake control device regulates the current applied to the actuator. The brake system 30 further includes a sensor that detects a current flowing through an auxiliary machine (eg, an actuator). The sensor transmits a signal indicating the detected current to the first monitoring unit 200. Further, the brake system 30 transmits information regarding an operation command to the actuator to the first monitoring unit 200.

The PCU 50 performs power conversion between the high voltage battery 90 and the MG 52. The PCU 50 includes, for example, an inverter that receives power from the high-voltage battery 90 to drive the MG 52, a converter that adjusts the level of the DC voltage supplied to the inverter (neither is shown), and the like.

The MG 52 is a three-phase AC rotary electric machine, for example, a permanent magnet type motive motor including a rotor in which a permanent magnet is embedded. The MG 52 has a function as an electric motor (motor) and a function as a generator (generator). The MG 52 is connected to the high voltage battery 90 via the PCU 50.

The MG 52 is driven by an inverter included in the PCU 50, for example, when the vehicle 1 is traveling. The power of the MG 52 is transmitted to the drive wheels (not shown). Further, in the MG 52, for example, when the vehicle 1 is braked, the MG 52 is driven by the drive wheels, and the MG 52 operates as a generator to perform regenerative braking. The electric power generated by the MG 52 is stored in the high voltage battery 90 via the PCU 50.

The power supply device 2 includes a DC / DC converter 40, a first relay 60, a second relay 70, a low voltage battery 80, a high voltage battery 90, a first monitoring unit 200, and a second monitoring unit 300.

The DC / DC converter 40 is connected to the high-voltage battery 90, which is a power supply source, via the second relay 70, and the HV system 10, the EPS system 20, the brake system 30, and the first are the power supply destinations. It is connected to the low voltage battery 80 via the relay 60. The DC / DC converter 40 charges the low-voltage battery 80 with the DC power output from the high-voltage battery 90 in response to the control signal from the first monitoring unit 200, for example, when the first relay 60 is in the ON state. It is converted into possible DC power or DC power capable of operating the HV system 10, EPS system 20 and brake system 30 and output to the low voltage battery 80. The DC / DC converter 40 is provided with, for example, a sensor that detects an output voltage, and the sensor transmits a signal indicating the detected output voltage to the first monitoring unit 200.

The first relay 60 electrically connects each of the HV system 10, the EPS system 20, the brake system 30, and the DC / DC converter 40 to the low-voltage battery 80 in response to the control signal from the first monitoring unit 200 ( Turn it on (on state) or shut it off (off state).

The second relay 70 electrically connects (on state) each of the DC / DC converter 40 and the PCU 50 and the high-voltage battery 90 in response to a control signal from the second monitoring unit 300, or cuts off (off state). State).

The low-voltage battery 80 is a power storage device capable of supplying electric power to each of a plurality of electric devices mounted as auxiliary machines in the vehicle 1. The auxiliary machine mounted on the vehicle 1 includes, for example, an electric device other than the electric device powered by the high voltage battery 90 among the plurality of electric devices mounted on the vehicle 1. Therefore, the auxiliary equipment includes, for example, a first monitoring unit 200 and a second monitoring unit 300. The low voltage battery 80 is, for example, a secondary battery such as a lead storage battery having a predetermined output voltage (for example, about 12V, about 24V, or about 48V).

The high voltage battery 90 is a power storage device and is a rechargeable DC power source. As the high-pressure battery 90, for example, a secondary battery such as a nickel hydrogen battery or a lithium ion battery is used. The high-voltage battery 90 is not limited to a secondary battery, and may be a battery capable of generating a DC voltage, for example, a capacitor or the like. The high-voltage battery 90 is, for example, an assembled battery having a predetermined output voltage (for example, several hundred volts) configured by combining a plurality of cells or battery modules.

The high-voltage battery 90 is used for exchanging electric power with and from the PCU 50, and is used for supplying electric power to the DC / DC converter 40.

The first monitoring unit 200 monitors the state of the low voltage battery 80. Specifically, the low voltage battery 80 is provided with, for example, a first temperature sensor 202, a first voltage sensor 204, and a first current sensor 206.

The first temperature sensor 202 detects the temperature TB of the low-voltage battery 80, and transmits a signal indicating the detected temperature TB to the first monitoring unit 200. The first voltage sensor 204 detects the voltage VB of the low voltage battery 80 and transmits a signal indicating the detected voltage VB to the first monitoring unit 200. The first current sensor 206 detects the current IB of the low voltage battery 80 and transmits a signal indicating the detected current IB to the first monitoring unit 200.

The first monitoring unit 200 includes, for example, a CPU (Central Processing Unit), a memory as a storage device, and an input / output buffer (none of which is shown). The first monitoring unit 200 is predetermined by executing signals from various sensors (first temperature sensor 202, first voltage sensor 204, first current sensor 206), a program stored in a memory, and the like using a CPU. Executes the processing of. The first monitoring unit 200 is configured to be able to communicate with the second monitoring unit 300 via a communication bus (not shown). The first monitoring unit 200 receives, for example, information about the state of the high voltage battery 90 from the second monitoring unit 300, or transmits information about the state of the low voltage battery 80 to the second monitoring unit 300.

The second monitoring unit 300 monitors the state of the high voltage battery 90. Specifically, the high voltage battery 90 is provided with, for example, a second temperature sensor 302, a second voltage sensor 304, and a second current sensor 306. The second monitoring unit 300 is configured to be able to communicate with the first monitoring unit 200 via a communication bus.

The second temperature sensor 302 detects the temperature TB2 of the high-voltage battery 90 and transmits a signal indicating the detected temperature TB2 to the second monitoring unit 300. The second voltage sensor 304 detects the voltage VB2 of the high voltage battery 90 and transmits a signal indicating the detected voltage VB2 to the second monitoring unit 300. The second current sensor 306 detects the current IB2 of the high voltage battery 90 and transmits a signal indicating the detected current IB2 to the second monitoring unit 300.

In the power supply device 2 mounted on the vehicle 1 having the above configuration, when an abnormality occurs in the low voltage battery 80, the low voltage battery 80 and the power supply destination (HV system 10, EPS system 20 and brake system 30). The first relay 60 is operated so that the and is cut off.

However, when an abnormality occurs in the low-voltage battery 80, it may be preferable to continue the power supply from the low-voltage battery 80 from the viewpoint of protecting the electric equipment mounted on the vehicle 1 depending on the degree of the abnormality. It is required to appropriately set the execution timing of the protection control that cuts off the power supply from the low voltage battery 80.

Therefore, in the present embodiment, when the abnormal state of the low-voltage battery 80 is the abnormal level 1, the first monitoring unit 200 has the first condition that the DC / DC converter 40 is operating and the low-voltage battery 80. It is assumed that the first relay 60 is controlled so as to be in the cutoff state when the cutoff permission condition including the second condition that is not in the discharge state is satisfied. Further, the first monitoring unit 200 continues to supply power from the low voltage battery 80 to each of the plurality of electric devices when the abnormal state of the low voltage battery 80 is the abnormality level 1 and the cutoff permission condition is not satisfied. And. Further, when the abnormal state of the low voltage battery 80 is the abnormal level 2 having a higher degree of abnormality than the abnormal state of the low voltage battery 80, the first monitoring unit 200 shuts off even if the shutoff permission condition is not satisfied. It is assumed that the first relay 60 is controlled so as to be in a state.

In this way, when the abnormal state of the low voltage battery 80 is the abnormal level 1, the first relay 60 is controlled so as to be in the cutoff state when the cutoff permission condition is satisfied, so that the first relay 60 is set. It is possible to protect the power supply device 2 while suppressing the subsequent operation of the auxiliary equipment from being affected even if the power supply is cut off. Further, when the abnormality level is 1, when the cutoff permission condition is not satisfied, the power supply to the auxiliary machine is continued, so that the operation of the auxiliary machine can be continued. Further, in the case of the abnormality level 2, the power supply device 2 can be protected because the first relay 60 is controlled so as to be in the cutoff state even if the cutoff permission condition is not satisfied.

Hereinafter, the processing executed by the first monitoring unit 200 will be described with reference to FIG. FIG. 2 is a flowchart showing an example of processing executed by the first monitoring unit 200. The processing shown in this flowchart is repeatedly executed by the first monitoring unit 200 at a predetermined processing cycle.

In step 100 (hereinafter, step is referred to as S) 100, the first monitoring unit 200 determines whether or not the low voltage battery 80 is in an abnormal state of abnormality level 2.

The first monitoring unit 200 uses the information acquired from the HV system 10, the EPS system 20, the brake system 30, the first temperature sensor 202, the first voltage sensor 204, and the first current sensor 206 in a normal state of the low-voltage battery 80. It is determined whether there is an abnormal state of abnormal level 1, an abnormal state of abnormal level 2, or an abnormal state of abnormal level 2.

The abnormal states of the low voltage battery 80 are, for example, a high temperature state, an overvoltage state, an undervoltage state, a discharge overcurrent state, a charge overcurrent state, a failure state of the first temperature sensor 202, and a first voltage sensor 204. The failure state of the first current sensor 206, the failure state of the first relay 60, and the failure state of the first monitoring unit 200 are included.

In the first monitoring unit 200, for example, when the temperature TB of the low-voltage battery 80 is higher than the threshold TB (1) and is equal to or lower than the threshold TB (2), the low-voltage battery 80 has an abnormality level of 1. It is determined that the temperature is high. The threshold value TB (2) is higher than the threshold value TB (1).

Further, the first monitoring unit 200 determines that the low voltage battery 80 is in a high temperature state of abnormal level 2 when, for example, the temperature TB of the low voltage battery 80 is higher than the threshold value TB (2). When the temperature TB of the low-voltage battery 80 is equal to or less than the threshold value TB (1), the first monitoring unit 200 determines that the temperature of the low-voltage battery 80 is in a normal state.

Further, in the first monitoring unit 200, for example, when the voltage VB of the low voltage battery 80 is higher than the threshold value VB (1) and is equal to or lower than the threshold value VB (2), the low voltage battery 80 is at an abnormal level. It is determined that the overvoltage state is 1. The threshold value VB (2) is higher than the threshold value VB (1).

Further, the first monitoring unit 200 determines that the low voltage battery 80 is in an abnormal level 2 overvoltage state, for example, when the voltage VB of the low voltage battery 80 is higher than the threshold value VB (2).

Further, in the first monitoring unit 200, for example, when the voltage VB of the low voltage battery 80 is lower than the threshold value VB (3) and is equal to or higher than the threshold value VB (4), the low voltage battery 80 is at an abnormal level. It is determined that the voltage is in the low voltage state of 1. The threshold value VB (4) is lower than the threshold value VB (3).

Further, the first monitoring unit 200 determines that the low voltage battery 80 is in the low voltage state of the abnormality level 2 when, for example, the voltage VB of the low voltage battery 80 is lower than the threshold value VB (4). The first monitoring unit 200 determines that the voltage of the low voltage battery 80 is in the normal state if the low voltage battery 80 is neither in the overvoltage state nor in the low voltage state.

Further, in the first monitoring unit 200, the current IB of the low voltage battery 80 is the current on the discharge side (for example, a positive value), the magnitude of which is larger than the threshold value IB (1), and the threshold is large. When the value is IB (2) or less, it is determined that the low-voltage battery 80 is in an abnormal level 1 discharge overcurrent state. The threshold value IB (1) is a value larger than the threshold value IB (2).

Further, in the first monitoring unit 200, when the current IB of the low voltage battery 80 is the current on the discharge side and its magnitude is larger than the threshold value IB (2), the discharge overcurrent of the low voltage battery 80 is abnormal level 2. Determined to be in a state.

Further, in the first monitoring unit 200, the current IB of the low voltage battery 80 is the current on the charging side (for example, a negative value), the magnitude of which is larger than the threshold value IB (1), and the threshold is large. When the value is IB (2) or less, it is determined that the low-voltage battery 80 is in an abnormal level 1 charge overcurrent state.

Further, in the first monitoring unit 200, when the current IB of the low voltage battery 80 is the current on the charging side and its magnitude is larger than the threshold value IB (2), the charging overcurrent of the low voltage battery 80 is abnormal level 2. Determined to be in a state. A threshold value for determining whether the discharge overcurrent state is abnormal level 1 or an abnormal level 2 and a threshold value for determining whether the charging overcurrent state is abnormal level 1 or abnormal level 2. And may have different values.

Further, the first monitoring unit 200 is, for example, when the temperature TB of the low voltage battery 80 detected by the first temperature sensor 202 is a temperature which cannot be normally taken (for example, when it exceeds a predetermined temperature range which can be usually taken). ), It is determined that the first temperature sensor 202 is in a failed state. In this case, the first monitoring unit 200 determines that the low voltage battery 80 is in an abnormal state of abnormality level 2.

Further, the first monitoring unit 200 is used, for example, when the voltage VB of the low voltage battery 80 detected by the first voltage sensor 204 is at a temperature which cannot be normally taken (for example, when it exceeds a predetermined voltage range which can be usually taken). ), It is determined that the first voltage sensor 204 is in a failed state. In this case, the first monitoring unit 200 determines that the low voltage battery 80 is in an abnormal state of abnormality level 2.

Further, the first monitoring unit 200 is used, for example, when the current IB of the low voltage battery 80 detected by the first current sensor 206 is at a temperature which cannot be normally taken (for example, when it exceeds a predetermined current range which can be usually taken). ), It is determined that the first current sensor 206 is in a failed state. In this case, the first monitoring unit 200 determines that the low voltage battery 80 is in an abnormal state of abnormality level 2.

Further, for example, the first monitoring unit 200 may have a current flowing through the low voltage battery 80 even though an operation command for setting the first relay 60 to be cut off is output to the first relay 60, or the low voltage battery 80. When the voltage does not reach a predetermined state, it is determined that the first relay 60 is in a failed state.

Further, for example, when the first monitoring unit 200 outputs an operation command for connecting the first relay 60 to the first relay 60 but no current flows through the low voltage battery 80, or the low voltage battery 80. When the voltage of the first relay 60 does not reach a predetermined state, it is determined that the first relay 60 is in a failed state.

When it is determined that the first relay 60 is in a failed state, the first monitoring unit 200 determines that the low voltage battery 80 is in an abnormal state of abnormality level 2.

Further, when the first monitoring unit 200 cannot communicate with another electric device (for example, the second monitoring unit 300) that is communicably connected, the first monitoring unit 200 is in a faulty state. judge. When determining such a failure state, the first monitoring unit 200 determines that the low voltage battery 80 is in an abnormal state of abnormality level 2.

When it is determined that the low voltage battery 80 is in the abnormal state of the abnormality level 2 (YES in S100), the process is transferred to S108. On the other hand, when it is determined that the low voltage battery 80 is not in the abnormal state of the abnormality level 2 (NO in S100), the processing is transferred to S102.

In S102, the first monitoring unit 200 determines whether or not the low voltage battery 80 is in an abnormal state of abnormality level 1. When the low-voltage battery 80 is determined to be in the abnormal state of abnormal level 1 by being in any of the above-mentioned abnormal states of the plurality of types of abnormal level 1 (YES in S102), the process is S104. Moved to.

In S104, the first monitoring unit 200 determines whether or not the relay cutoff permission flag is in the off state. The relay cutoff permission flag is a flag indicating whether or not the cutoff permission condition is satisfied.

For example, the first monitoring unit 200 turns on the relay cutoff permission flag when the cutoff permission condition is satisfied, and turns off the relay cutoff permission flag when the cutoff permission condition is not satisfied.

For example, when at least one of the following plurality of conditions is satisfied, the first monitoring unit 200 determines that the cutoff permission condition is not satisfied, and turns off the relay cutoff permission flag. Further, the first monitoring unit 200 determines that the cutoff permission condition is satisfied when none of the following plurality of conditions are satisfied, and turns on the relay cutoff permission flag.

The plurality of conditions are, for example, that the low pressure battery 80 is being discharged, that the DC / DC converter 40 is not operating, and that the current required in the braking system 30 is equal to or greater than the threshold value. It includes a condition and a condition that the current required in the EPS system 20 is equal to or greater than the threshold value or the surge current is equal to or greater than the threshold value.

For example, when the current IB of the low-voltage battery 80 is the value on the discharge side, the first monitoring unit 200 determines that the condition that the low-voltage battery 80 is being discharged is satisfied.

Further, the first monitoring unit 200 is, for example, when an operation command is not output to the DC / DC converter 40 or when the output voltage of the DC / DC converter 40 is lower than a predetermined range indicating an operating state. , It is determined that the condition that the DC / DC converter 40 is not operating is satisfied.

Further, the first monitoring unit 200 starts a predetermined operation (for example, the vehicle 1) when the actuator of the brake system 30 is executing a predetermined operation (for example, anti-lock control at the time of sudden braking). The condition that the wheels are locked while the vehicle is running) is satisfied, or when the current flowing through the actuator of the brake system 30 is equal to or greater than the threshold value, the current required by the brake system 30 is the threshold value. It is determined that the above condition is satisfied.

Further, when the actuator of the EPS system 20 is executing a predetermined operation (for example, assist control at the time of a sharp turn), the first monitoring unit 200 starts a predetermined operation (for example, rotation of the handle). When the condition that the speed is equal to or higher than the threshold value) is satisfied, or when the current flowing through the actuator of the EPS system 20 is equal to or higher than the threshold value, the current required by the EPS system 20 is equal to or higher than the threshold value. It is determined that the condition is satisfied.

Alternatively, the first monitoring unit 200 generates a surge current when the surge current generated by the road surface reaction force being input to the actuator of the EPS system 20 such as when the steering wheel rides on a curb is equal to or higher than the threshold value. It is determined that the condition that the value is equal to or higher than the threshold value is satisfied.

When the first monitoring unit 200 determines that the relay cutoff permission flag is in the off state (YES in S104), the process is transferred to S106. Further, when it is determined in S102 that the low voltage battery 80 is not in the abnormal state of the abnormality level 1 (that is, it is in the normal state), the process is transferred to S106.

In S106, the first monitoring unit 200 controls the first relay 60 to be in the connected state. Specifically, the first monitoring unit 200 sets the cutoff request flag of the first relay 60 to the off state. The cutoff request flag is a flag indicating a state in which the cutoff of the first relay 60 is requested. When the cutoff request flag is off and the first relay 60 is in the connected state, the first monitoring unit 200 continues the connected state of the first relay 60. Further, the first monitoring unit 200 controls the first relay 60 so as to be in the connected state when the cutoff request flag is in the off state and the first relay 60 is in the cutoff state.

If it is determined in S104 that the relay cutoff permission flag is not in the off state (that is, it is in the on state) (NO in S104), the process is transferred to S108.

In S108, the first monitoring unit 200 controls the first relay 60 so as to be in the cutoff state. Specifically, the first monitoring unit 200 sets the cutoff request flag of the first relay 60 to the ON state. When the cutoff request flag is on and the first relay 60 is in the connected state, the first monitoring unit 200 controls the first relay 60 so as to be in the cutoff state. Further, when the cutoff request flag is on and the first relay 60 is in the cutoff state, the first monitoring unit 200 continues the cutoff state of the first relay 60.

The operation of the power supply device 2 according to the present embodiment based on the above structure and the flowchart will be described with reference to FIG.

FIG. 3 is a diagram for explaining a relay cutoff request flag set by a combination of the abnormal level of the low voltage battery 80 and the state of the relay cutoff permission flag. In FIG. 3, the state of the low-voltage battery 80 is divided into a normal state, an abnormal state of abnormal level 1, and an abnormal state of abnormal level 2, and the relay is shown in each case. The state of the cutoff request flag when the cutoff permission flag is on and the state of the cutoff request flag when the relay cutoff permission flag is off are shown.

For example, if any one of the first temperature sensor 202, the first voltage sensor 204, and the first current sensor 206 fails and the low pressure battery 80 is determined to be in an abnormal state of abnormality level 2 (in S100). YES), as shown in FIG. 3, the cutoff request flag is set to the on state regardless of whether the relay cutoff permission flag is on or off. Therefore, the first relay 60 is controlled so as to be in the cutoff state (S108).

On the other hand, for example, when the temperature TB of the low voltage battery 80 is higher than the threshold value TB (1) and is equal to or lower than the threshold value TB (2), the abnormal state of the low voltage battery 80 is the abnormality level 2. Since it is determined that the abnormal state is not an abnormal state (NO in S100) and is an abnormal state of abnormality level 1 (YES in S102), it is determined whether or not the relay cutoff permission flag is in the off state (S104). ..

For example, when the low-voltage battery 80 is being discharged, the relay cutoff permission flag is turned off because the cutoff permission condition is not satisfied (YES in S104). Therefore, as shown in FIG. 3, when the low-voltage battery 80 is in the abnormal state of the abnormality level 1 and the relay cutoff permission flag is in the off state, the cutoff request flag is set to the off state. Therefore, the first relay 60 is controlled so as to be in the connected state (S106).

On the other hand, if the low-voltage battery 80 is not discharging, the DC / DC converter 40 is operating, and neither the actuator of the brake system 30 nor the actuator of the EPS system requires a current exceeding the threshold value, cutoff is permitted. Since the condition is satisfied, the relay cutoff permission flag is turned on (NO in S104). Therefore, as shown in FIG. 3, when the low voltage battery 80 is in the abnormal state of the abnormality level 1 and the relay cutoff permission flag is in the on state, the cutoff request flag is set in the on state. As a result, the first relay 60 is controlled so as to be in the cutoff state (S108).

Further, for example, when the temperature TB of the low-voltage battery 80 becomes equal to or lower than the threshold value B (1) and the low-voltage battery 80 becomes a normal state (NO in S100, NO in S102), as shown in FIG. , The cutoff request flag is set to the off state regardless of whether the relay cutoff permission flag is on or off. Therefore, the first relay 60 is controlled so as to be in the connected state (S106).

As described above, according to the power supply device 2 according to the present embodiment, when the abnormal state of the low voltage battery 80 is the abnormal state of the abnormal level 1, the shutoff state is set when the cutoff permission condition is satisfied. Since the first relay 60 is controlled, even if the first relay 60 is cut off, the operation of the auxiliary equipment (for example, the auxiliary equipment of the HV system 10, the EPS system 20 and the brake system 30) after that is affected. It is possible to protect the power supply device 2 while suppressing the above. Further, in the case of the abnormal state of the abnormality level 1, when the cutoff permission condition is not satisfied, the power supply to the auxiliary machine is continued, so that the operation of the auxiliary machine can be continued. Further, in the case of the abnormal state of the abnormality level 2, the power supply device 2 can be protected because the first relay 60 is controlled so as to be in the cutoff state even if the cutoff permission condition is not satisfied. .. Therefore, it is possible to provide a power supply device that executes protection control at an appropriate time when an abnormality occurs in the power supply device.

Hereinafter, modification examples will be described.
In the above embodiment, the plurality of conditions are the condition that the low voltage battery 80 is being discharged, the condition that the DC / DC converter 40 is not operating, and the current required in the braking system 30. None of the plurality of conditions including the condition that the value is equal to or higher than the value and the condition that the current required in the EPS system 20 is equal to or higher than the threshold value or the surge current is equal to or higher than the threshold value is not satisfied. Although it has been described as determining that the cutoff permission condition is satisfied in this case, for example, the condition that the DC / DC converter 40 is in the non-operating state and the condition that the low voltage battery 80 is in the discharged state are not satisfied. (That is, when the DC / DC converter 40 is in operation and the low-voltage battery 80 is not in the discharged state), it may be determined that the cutoff permission condition is satisfied.

Further, in the above-described embodiment, the case where the vehicle 1 is a hybrid vehicle has been described as an example, but the vehicle 1 may be a vehicle equipped with a low-pressure battery and an electric device powered by the low-pressure battery, for example. It may be an electric vehicle or a vehicle equipped with an engine.

Hereinafter, the configuration when the vehicle 1 is a vehicle equipped with an engine will be described. FIG. 4 is a block diagram schematically showing an example of the overall configuration of a vehicle equipped with the power supply device 2 according to the modified example.

As shown in FIG. 4, the vehicle 1 in this modification includes a power supply device 2, an EFI (Electric Fuel Injection) system 12, an EPS (Electric Power Steering) system 20, and a brake system 30.

The EFI system 12 includes electrical equipment that acts as an auxiliary machine when fueling the engine. Electrical equipment that operates as an auxiliary machine when supplying fuel to an engine includes, for example, a fuel injection device and a fuel control device that controls the fuel injection device. The EFI system 12 further includes a sensor that detects a current flowing through an auxiliary machine (eg, a fuel injection device). The sensor transmits a signal indicating the detected current to the first monitoring unit 200. Further, the EFI system 12 transmits information regarding an operation command to the fuel injection device to the first monitoring unit 200.

Since the EPS system 20 and the brake system 30 have the same configurations as the EPS system 20 and the brake system 30 described with reference to FIG. 1, the detailed description thereof will not be repeated.

The power supply device 2 according to this modification includes an alternator 42, a first relay 60, a low voltage battery 80, and a first monitoring unit 200.

The alternator 42 is a generator that uses the power of the engine to generate electricity when the engine is operating. The alternator 42 is connected to the output shaft of the engine via, for example, a belt or the like, and the power generation operation can be performed by rotating the output shaft of the engine and rotating the rotor built in the alternator 42. The electric power generated in the alternator 42 is supplied to the low voltage battery 80 via the first relay 60, or is supplied to the EFI system 12, the EPS system 20, and the brake system 30.

Even in the power supply device 2 configured in this way, when the abnormal state of the low-voltage battery 80 is the abnormal level 1 of the first monitoring unit 200, the first condition that the alternator 42 is operating and the low-voltage battery 80 It is assumed that the first relay 60 is controlled so as to be in the cutoff state when the cutoff permission condition including the second condition that the current exceeding the threshold value is not in the discharge state is satisfied. Further, the first monitoring unit 200 continues to supply power from the low voltage battery 80 to each of the plurality of electric devices when the abnormal state of the low voltage battery 80 is the abnormality level 1 and the cutoff permission condition is not satisfied. And. Further, when the abnormal state of the low voltage battery 80 is the abnormal level 2 having a higher degree of abnormality than the abnormal state of the low voltage battery 80, the first monitoring unit 200 shuts off even if the cutoff permission condition is not satisfied. It is assumed that the first relay 60 is controlled so as to be in a state.

In this way, when the abnormal state of the low voltage battery 80 is the abnormal level 1, the first relay 60 is controlled so as to be in the cutoff state when the cutoff permission condition is satisfied, so that the first relay 60 is set. It is possible to protect the power supply device 2 while suppressing the subsequent operation of the auxiliary equipment from being affected even if the power supply is cut off. Further, when the abnormality level is 1, when the cutoff permission condition is not satisfied, the power supply to the auxiliary machine is continued, so that the operation of the auxiliary machine can be continued. Further, in the case of the abnormality level 2, the power supply device 2 can be protected because the first relay 60 is controlled so as to be in the cutoff state even if the cutoff permission condition is not satisfied.

In addition, the above-mentioned modification may be carried out by appropriately combining all or a part thereof.
It should be considered that the embodiments disclosed this time are exemplary in all respects and not restrictive. The scope of the present invention is shown by the scope of claims rather than the above description, and is intended to include all modifications within the meaning and scope equivalent to the scope of claims.

1 vehicle, 2 power supply, 10 HV system, 12 EFI system, 20 EPS system, 30 brake system, 40 DC / DC converter, 42 alternator, 60 1st relay, 70 2nd relay, 80 low voltage battery, 90 high voltage battery, 200 1st monitoring unit, 202 1st temperature sensor, 204 1st voltage sensor, 206 1st current sensor, 300 2nd monitoring unit, 302 2nd temperature sensor, 304 2nd voltage sensor, 306 2nd current sensor.

Claims (1)

A secondary battery that can supply power to each of multiple electrical devices that operate as auxiliary equipment while the vehicle is driving.
An electric power supply device capable of supplying electric power to the plurality of electric devices during a part of the operation of the vehicle, and an electric power supply device.
A relay capable of cutting off the power supply from the secondary battery to each of the plurality of electric devices,
A detection device that detects the abnormal state of the secondary battery, and
A control device for controlling the relay using the detection result by the detection device, the state of the secondary battery, and the operating state of the power supply device is provided.
The control device is
When the abnormal state of the secondary battery detected by the detection device is the first abnormal state, the first condition that the power supply device is operating and the second condition that the secondary battery is not in the discharged state. When the cutoff permission condition including the condition is satisfied, the relay is controlled so as to be in the cutoff state.
When the abnormal state of the secondary battery is the first abnormal state, when the cutoff permission condition is not satisfied, the power supply from the secondary battery to each of the plurality of electric devices is continued.
When the abnormal state of the secondary battery is the second abnormal state in which the degree of abnormality is higher than that in the case of the first abnormal state, the shutoff state is reached even if the cutoff permission condition is not satisfied. A power supply that controls the relay so as to.

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