JP7679783B2 - Anomaly detection device and program - Google Patents

Description

The present invention relates to an abnormality detection device and program.

Conventionally, there are known abnormality detection devices that detect abnormalities in resolvers and the like. For example, in Patent Document 1, an abnormality inside the resolver or in the wiring is detected based on the sum of squares of the sine signal and cosine signal obtained from the resolver.

Japanese Patent Application Publication No. 9-72758

For example, in a device that requires a boost power supply to operate a resolver or the like, if an abnormality determination is performed while the boost circuit is stopped, there is a risk that the resolver signal will be erroneously determined to be abnormal, even though the resolver itself is normal. The same applies to devices other than resolvers that use a boost power supply.

The present invention has been made in consideration of the above-mentioned problems, and its purpose is to provide an abnormality detection device and program that can prevent erroneous abnormality determination.

The abnormality detection device of the present invention includes a boost circuit (31), an internal power supply (41, 42), a boosted power supply-using component (15, 45, 47), and a control unit (50). The boost circuit boosts the power from the battery (7). The internal power supply supplies the power boosted by the boost circuit. The boosted power supply-using component operates using the power supplied from the internal power supply.

The control unit has a drive signal generation unit (51) that generates a boost circuit drive signal that drives the boost circuit, and an abnormality determination unit (55) that determines an abnormality related to a component that uses a boost power supply. When the operation of the boost circuit is stopped by turning off the boost circuit drive signal, the abnormality determination unit controls to disable abnormality determination related to the component that uses the boost power supply. This makes it possible to avoid erroneous determination of an abnormality in the component that uses the boost power supply.

The present invention is also provided as a program for operating an abnormality determination unit in an abnormality detection device. This provides the same effects as the abnormality determination device.

1 is a block diagram showing a configuration of a vehicle drive system according to an embodiment; FIG. 2 is a block diagram showing a configuration of a control unit according to one embodiment. 10 is a flowchart illustrating an abnormality monitoring execution determination process according to an embodiment. 4 is a time chart illustrating an abnormality monitoring execution determination process according to an embodiment.

(One embodiment)
An abnormality detection device according to the present invention will be described below with reference to the drawings. One embodiment is shown in Figures 1 to 4. As shown in Figure 1, a vehicle drive system 1 includes a main battery 5, an auxiliary battery 7, a main motor 10, and a power control unit 20.

The main battery 5 is a DC power source consisting of a chargeable and dischargeable secondary battery, such as a nickel-metal hydride or lithium ion battery. The power of the main battery 5 is supplied to the main motor 10 mainly via a bridge circuit 22 and is used to drive the main motor 10. The main battery 5 is charged with power generated by regeneration of the main motor 10. The main battery 5 can also be charged by an external power source (not shown). The auxiliary battery 7 is a secondary battery, such as a lead storage battery, and supplies power to the control unit 30 and auxiliary devices (not shown).

The main motor 10 is a permanent magnet type synchronous three-phase AC rotating electric machine, a so-called "motor generator" that functions both as an electric motor and as a generator. The main motor 10 is used as a driving source for the vehicle. The vehicle may be an EV vehicle that runs on the driving force of the main motor 10, or a hybrid vehicle that runs on the driving force of the main motor 10 and an engine (not shown). The main motor 10 is provided with a resolver 15, which is a rotation angle sensor that detects the rotation angle.

As shown in Figures 1 and 2, the power control unit 20 has an inverter 21, a control unit 30, etc. The inverter 21 has a bridge circuit 22, and a temperature sensor 25. The bridge circuit 22 has inverter elements such as IGBTs connected in a bridge configuration, converts DC power supplied from the main battery 5 into three-phase AC power, and outputs it to the main motor 10. The temperature sensor 25 detects the temperature of the inverter elements that make up the bridge circuit 22. In the figures, the power control unit is referred to as "PCU" and the control unit is referred to as "ECU."

2, the control unit 30 includes a boost circuit 31, a first internal power supply 41, a second internal power supply 42, a resolver excitation circuit 45, a gate drive IC 47, and a control unit 50, and operates on power from the auxiliary battery 7. The boost circuit 31 has a boost element such as an IGBT, and boosts the voltage of the auxiliary battery 7 (e.g., 12 V) by switching the boost element to generate boost voltages for the first internal power supply 41 and the second internal power supply 42. In this embodiment, the first internal power supply 41 is, for example, a 30 V power supply, and the second internal power supply is, for example, a 17 V power supply, but the number of internal power supplies and the boost voltage may be different.

The resolver excitation circuit 45 generates a resolver excitation signal using power supplied from the first internal power supply 41. The generated resolver excitation signal is output to the resolver 15. The resolver 15 uses the resolver excitation signal to output a sine signal and a cosine signal, which are angle signals corresponding to the rotational position of the main motor 10, to the control unit 50. In addition, the RDC (resolver digital converter) 16 performs angle calculation based on the sine signal and the cosine signal output from the resolver 15, and outputs an angle calculation signal to the control unit 50 as a digital signal. Hereinafter, the sine signal and the cosine signal output from the resolver 15 are referred to as resolver signals, and the signal from the RDC 16 is referred to as an RDC signal, as appropriate.

The gate drive IC 47 is supplied with power from the second internal power supply 42 and outputs a gate signal to the inverter 21. The gate drive IC 47 also acquires the detection value of the temperature sensor 25 and the detection value of a current sensor (not shown) as inverter element information. The gate drive IC 47 outputs a temperature detection signal, which is a pulse signal whose duty is changed according to the inverter element temperature, to the control unit 50.

The control unit 50 is mainly composed of a microcomputer and includes a CPU, ROM, RAM, I/O, and bus lines connecting these components (none of which are shown). Each process in the control unit 50 may be software processing in which the CPU executes a program prestored in a physical memory device such as a ROM (i.e., a readable non-transitory tangible recording medium), or it may be hardware processing using a dedicated electronic circuit. The control unit 50 is supplied with power from the auxiliary battery 7 via a regulator (not shown) without passing through the boost circuit 31.

The control unit 50 has, as functional blocks, a drive signal generation unit 51, an angle calculation unit 52, a temperature calculation unit 53, and an abnormality determination unit 55. The drive signal generation unit 51 generates a boost circuit drive signal related to driving the boost circuit 31 and outputs it to the boost circuit 31.

The angle calculation unit 52 obtains the AD converted values of the sine and cosine signals output from the resolver 15, and calculates information related to the rotational position of the main motor 10 by a tan calculation or the like. The information related to the rotational position of the main motor 10 includes the number of rotations, the resolver angle, and the electrical angle.

The temperature calculation unit 53 acquires a temperature detection signal related to the inverter element temperature from the gate drive IC 47, and calculates the inverter element temperature based on the duty of the acquired temperature detection signal.

The abnormality determination unit 55 monitors abnormalities in the resolver 15, the inverter element, the first internal power supply 41, etc. Specifically, the abnormality determination unit 55 monitors the sum of the squares of the sine signal and the cosine signal output from the resolver 15, and determines that the resolver 15 is abnormal if the sum of the squares of the sine signal and the cosine signal falls outside a predetermined range. Note that resolver abnormalities include not only abnormalities in the resolver 15 itself, but also abnormalities in the wiring from the resolver 15 to the control unit 50. The same applies to other abnormalities.

The abnormality determination unit 55 compares the angle information based on the resolver signal acquired from the resolver 15 with the angle information acquired from the RDC 16, and if the difference is outside the coincidence determination range, it determines that an angle calculation abnormality has occurred. The abnormality determination unit 55 also receives an excitation period signal, which is a pulse signal output for each period of the excitation signal, from the resolver excitation circuit 45 and monitors the excitation signal period. If the excitation period signal cannot be acquired from the resolver excitation circuit 45 or if the signal period is outside the normal range, the abnormality determination unit 55 determines that the resolver excitation signal is abnormal.

The abnormality determination unit 55 monitors the temperature detection signal output from the gate drive circuit 47. If the abnormality determination unit 55 cannot obtain the temperature detection signal or if the inverter element temperature is outside the normal range, it determines that there is a temperature detection abnormality. In addition, the abnormality determination unit 55 obtains a voltage obtained by converting the power supply voltage of the first internal power supply 41, which is the power supply for the resolver excitation circuit 45, into a predetermined range (for example, 0 [V] to 5 [V]), and monitors whether the first internal power supply 41 is within the normal operating range. If the voltage of the first internal power supply 41 is outside the normal operating range, the abnormality determination unit 55 determines that there is an abnormality in the power supply voltage of the resolver excitation circuit 45. Note that some control lines have been omitted from FIG. 2 to avoid complication.

The resolver excitation circuit 45 and the gate drive IC 47 require a voltage higher than that of the auxiliary battery 7, so they are configured to supply power via internal power sources 41 and 42 generated using the boost circuit 31.

When generating the boost voltage, the boost circuit 31 switches the boost element, generating noise. In addition, as vehicles become more electrified, EMC (Electromagnetic Compatibility) requirements tend to become stricter. For example, if the boost circuit 31 is operating when charging the main battery 5 from an external power source, there is a possibility that the EMC requirements will not be met due to switching noise.

Therefore, in this embodiment, when the main battery 5 is being charged, the operation of the boost circuit 31, which boosts the voltage of the auxiliary battery 7, is stopped. When the operation of the boost circuit 31 is stopped, the operation of the resolver excitation circuit 45 and the like, which are operated by power supplied from the internal power sources 41, 42, is stopped. Hereinafter, the parts that are operated by power supplied from the internal power sources 41, 42 are collectively referred to as "components using boost power supply".

On the other hand, because the control unit 50 receives power from the auxiliary battery 7 without passing through the boost circuit 31, it continues to operate even when the boost circuit 31 is stopped. If the abnormality determination unit 55 continues to monitor for abnormalities in the resolver 15, which is powered by the internal power sources 41 and 42 and operates, there is a risk that the resolver 15 may be erroneously determined to be abnormal even though it is actually normal.

Therefore, in this embodiment, when the boost circuit 31 is normally stopped by command from the control unit 50, such as when the main battery 5 is being charged, abnormality monitoring of components that use the internal power supplies 41 and 42 is disabled.

The abnormality monitoring implementation determination process of this embodiment will be described with reference to the flowchart in FIG. 3. This process is executed at a predetermined cycle by the control unit 50. Hereinafter, the "step" such as step S101 will be omitted and simply referred to as the symbol "S".

In S101, the control unit 50 acquires charging information related to the charging state of the main battery 5 from the vehicle system. In S102, the control unit 50 determines whether the main battery 5 is being charged by an external power source. If it is determined that the main battery 5 is being charged (S102: YES), the process proceeds to S103. Note that in this case, charging is not by regeneration, and the main motor 10 is stopped. If it is determined that the main battery 5 is not being charged (S102: NO), the process proceeds to S105.

In S103, the drive signal generating unit 51 turns off the boost circuit drive signal and stops the boost circuit 31. In S104, the abnormality determination unit 55 disables abnormality determination related to the components using the boost power supply. Specifically, the abnormality determination unit 55 disables abnormality determination of the resolver signal based on the sum of squares of the sine signal and cosine signal acquired from the resolver 15, abnormality determination of the resolver excitation circuit based on the excitation period signal acquired from the resolver excitation circuit 45, abnormality determination of the angle calculation by comparing the angle calculation value based on the resolver signal with the angle calculation value based on the RDC signal, abnormality determination of the inverter element temperature based on the temperature detection signal acquired from the gate drive IC 47, and abnormality determination of the internal power supply voltage. Also, if the boost drive signal is off and abnormality monitoring related to the components using the boost power supply is disabled, the state is maintained.

If it is determined that the main battery 5 is not being charged (S102: NO), the control unit 50 proceeds to S105, where it determines whether the boost circuit 31 is in operation. If it is determined that the boost circuit 31 is in operation (S105: YES), the control unit 50 skips the processing from S106 onwards and continues to operate the boost circuit 31. If it is determined that the boost circuit 31 is stopped (S105: NO), it proceeds to S106. In S106, the drive signal generation unit 51 turns on the boost circuit drive signal and starts operating the boost circuit 31.

In S107, the abnormality determination unit 55 determines whether the abnormality monitoring recovery condition is satisfied. Here, it is determined that the abnormality monitoring recovery condition is satisfied when the waiting time Xw has elapsed since the boost circuit 31 started to operate. The waiting time Xw is set according to the time required for the voltages of the internal power supplies 41 and 42 to stabilize after the boost circuit 31 starts to operate.

It may also be determined that the abnormality monitoring recovery condition is met by receiving a notification that a function that is activated after the boost circuit 31 is driven has been activated. For example, it may be determined that the abnormality monitoring recovery condition is met when the voltage of the first internal power supply 41 is within a normal range as a function that is activated after the boost circuit 31 is driven. Furthermore, it may also be determined that the abnormality monitoring recovery condition is met when the pulse signal obtained from the resolver excitation circuit 45 has a normal amplitude and period.

If it is determined that the abnormality monitoring recovery condition is not met (S107: NO), this determination process is repeated. If it is determined that the abnormality monitoring recovery condition is met (S107: YES), the process proceeds to S108, where abnormality monitoring for components using boost power is performed.

The abnormality monitoring implementation determination process according to this embodiment will be described based on the time chart in Figure 4. In Figure 4, the horizontal axis represents a common time axis, and from the top, the charging implementation state of the main battery 5, the driving state of the boost circuit 31, the implementation state of resolver abnormality monitoring, the state of the resolver 15, the resolver signal, and the sum of squares of the resolver signal are shown. Note that Figure 4 shows abnormality monitoring based on the sum of squares of the resolver signal as an example of abnormality monitoring related to components that use a boost power source.

Before time x10, the main battery 5 is not charging and the boost circuit 31 is operating normally. In addition, the resolver 15 is normal and the sum of the squares of the resolver signal is the predetermined value A, so the abnormality determination unit 55 determines that the resolver 15 is normal.

When charging of the main battery 5 starts at time x10, the drive signal generation unit 51 turns off the boost circuit drive signal and stops driving the boost circuit 31. When the drive of the boost circuit 31 stops, the resolver excitation circuit 45 cannot generate an excitation signal, so the resolver signal becomes fixed at a predetermined value (0 in the example of FIG. 4) and the sum of the squares of the resolver signal also becomes 0, which is a value different from the predetermined value A. Therefore, if abnormality monitoring continues after time x10, the abnormality determination unit 55 will erroneously determine that there is an abnormality in the resolver 15.

Therefore, in this embodiment, abnormality monitoring of the resolver signal is disabled while the main battery 5 is charging. This makes it possible to avoid erroneously determining that the resolver 15 is abnormal when it is actually normal. However, abnormality monitoring of components other than those using a boost power supply may continue even while the main battery 5 is charging.

When charging of the main battery 5 ends at time x11, the drive signal generating unit 51 turns on the boost circuit drive signal at time x12, and the boost circuit 31 starts to be driven. When the boost circuit 31 starts to be driven, the first internal power supply 41 starts up, and an excitation signal is generated from the resolver excitation circuit 45. There is a delay from the start of driving the boost circuit 31 until the excitation signal returns to normal. In this embodiment, taking into account the delay from the start of driving the boost circuit 31, the boost circuit drive signal is turned on, and at time x13 when the waiting time Xw has elapsed, abnormality monitoring based on the sum of squares of the resolver signal in the abnormality determining unit 55 is started. This makes it possible to avoid erroneously determining that the delay from the start of driving the boost circuit 31 until the resolver signal becomes stable is an abnormality in the resolver 15.

As described above, the control unit 30 includes the boost circuit 31, the internal power sources 41 and 42, the components that use the boosted power source, and the control unit 50. The boost circuit 31 boosts the power from the auxiliary battery 7. The internal power sources 41 and 42 supply the power boosted by the boost circuit 31. The components that use the boosted power source operate using the power supplied from the internal power sources 41 and 42.

The control unit 50 has a drive signal generation unit 51 and an abnormality determination unit 55. The drive signal generation unit 51 generates a boost circuit drive signal that drives the boost circuit 31. The abnormality determination unit 55 determines an abnormality related to the components using the boost power supply. When the drive of the boost circuit 31 is stopped normally by turning off the boost circuit drive signal, the abnormality determination unit 55 controls to disable abnormality determination related to the components using the boost power supply. This makes it possible to avoid erroneously determining that a state in which a signal related to abnormality determination of the components using the boost power supply differs from normal due to the stop of the boost circuit 31 is an abnormality in the components using the boost power supply.

When the boost circuit drive signal is turned on from off and the boost circuit 31 starts to drive, the abnormality determination unit 55 starts abnormality determination for the components using the boost power supply after the recovery condition is satisfied. This makes it possible to avoid erroneously determining that the delay between when the boost circuit 31 starts up and when the components using the boost power supply start to operate normally is an abnormality.

The component using the boost power supply is the resolver 15 that detects the rotational position of the main motor 10, and the abnormality determination unit 55 disables abnormality determination of the signal acquired from the resolver 15 when the drive of the boost circuit 31 is stopped. In detail, it disables abnormality determination based on the sum of the squares of the sine signal and cosine signal acquired from the resolver 15. This makes it possible to avoid erroneously determining that a state in which the resolver signal is a different value from normal due to the boost circuit 31 being stopped is an abnormality in the resolver 15.

In addition, when the operation of the boost circuit is stopped, the abnormality determination unit 55 disables the abnormality determination of the voltage supplied to the resolver excitation circuit 45 (the voltage of the first internal power supply 41 in this embodiment). This makes it possible to prevent erroneous determination of an abnormality in the resolver excitation circuit power supply.

The boost power supply-using component is the resolver excitation circuit 45, which outputs an excitation signal to the resolver 15 that detects the rotational position of the main motor 10. When the drive of the boost circuit 31 is stopped, the abnormality determination unit 55 disables the abnormality determination of the excitation periodic signal that is periodically output from the resolver excitation circuit. This makes it possible to prevent erroneous determination of an abnormality in the resolver excitation circuit 45.

The boost power supply using component is the gate drive IC 47 that outputs a gate signal to the inverter element that constitutes the inverter 21, and the abnormality determination unit 55 disables abnormality determination of the signal related to the inverter element information output from the gate drive IC 47 when the drive of the boost circuit 31 is stopped. The inverter element information is, for example, the temperature of the inverter element. This makes it possible to avoid erroneous determination of an abnormality in the inverter element information.

In addition, when the drive of the boost circuit 31 is stopped, the abnormality determination unit 55 disables abnormality determination based on a comparison between the angle calculation value based on the signal obtained from the resolver 15 and the angle calculation value obtained via the resolver digital converter 16. This makes it possible to avoid erroneous determination of an abnormality in the angle calculation.

In addition, the program of the abnormality detection device that detects abnormalities related to components that use a boost power supply operates the abnormality determination unit 55, which controls to disable abnormality determination related to components that use the boost circuit, when the boost circuit 31 is stopped by turning off the boost drive circuit signal. Such a program also has the same effect.

In this embodiment, the control unit 30 corresponds to the "abnormality detection device," the auxiliary battery 7 corresponds to the "battery," the main motor 10 corresponds to the "motor," and the gate drive IC 47 corresponds to the "gate drive circuit."

Other Embodiments
In the above embodiment, when the boost circuit is stopped while the main battery is being charged, the following are invalidated: abnormality determination of the resolver signal based on the sum of squares of the sine signal and cosine signal from the resolver, abnormality determination of the resolver excitation circuit, abnormality determination of the angle calculation, abnormality determination of the inverter element temperature, and abnormality determination of the internal power supply voltage. In other embodiments, some of the abnormality determinations that are invalidated when the boost circuit is stopped may be omitted, or other abnormality determinations related to components that use the boost power supply may be invalidated.

In the above embodiment, the components using the boosted power supply are the resolver, the resolver excitation circuit, and the gate drive circuit. In other embodiments, the components using the boosted power supply may be other than the resolver, the resolver excitation circuit, and the gate drive circuit that operate with power boosted by the boost circuit. Also, when the boost circuit is stopped, abnormality monitoring based on other than the sum of squares of the sine signal and cosine signal from the resolver, the resolver excitation circuit power supply voltage, and the pulse signal from the resolver excitation circuit or the gate drive circuit may be stopped.

In the above embodiment, if the boost circuit is stopped while the main battery is charging, the abnormality determination for the components using the boost power source is invalidated. In another embodiment, if the power supply to the control unit continues at a time other than when the main battery is charging and the boost circuit is normally stopped by a command from the control unit, the abnormality determination for the components using the boost power source may be invalidated.

In the above embodiment, the control unit acquires information related to the motor rotational position via the resolver and the RDC. In other embodiments, the RDC may be omitted. Also, the configuration of the control unit may differ from that of the above embodiment, for example, by using a rotation angle sensor other than a resolver.

The control unit and the method described in the present disclosure may be realized by a dedicated computer provided by configuring a processor and a memory programmed to execute one or more functions embodied in a computer program. Alternatively, the control unit and the method described in the present disclosure may be realized by a dedicated computer provided by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the control unit and the method described in the present disclosure may be realized by one or more dedicated computers configured by combining a processor and a memory programmed to execute one or more functions with a processor configured with one or more hardware logic circuits. In addition, the computer program may be stored in a computer-readable non-transient tangible recording medium as instructions executed by a computer. As described above, the present invention is not limited to the above embodiment, and can be implemented in various forms within the scope of the invention.

7. Auxiliary battery (battery)
10...Main motor (motor)
15...Resolver (component using boost power supply)
30: Control unit (abnormality detection device)
31: Boost circuit 41, 42: Internal power supply 45: Resolver excitation circuit (component using boost power supply)
47...Gate driving IC (components using boosted power supply, gate driving circuit)
50: Control unit 51: Drive signal generating unit 55: Abnormality determining unit

Claims (8)

A boost circuit (31) for boosting the power from the battery (7);
an internal power supply (41, 42) for supplying power boosted by the boost circuit;
A boosted power supply component (15, 45, 47) that operates using power supplied from the internal power supply;
a control unit (50) having a drive signal generating unit (51) for generating a boost circuit drive signal for driving the boost circuit, and an abnormality determining unit (55) for determining an abnormality related to a component using a boost power supply;
Equipped with
The abnormality detection device, wherein the abnormality determination unit performs control so as to disable abnormality determination related to the component using the boost power supply when the boost circuit drive signal is turned off to stop driving the boost circuit. The abnormality detection device according to claim 1, wherein the abnormality determination unit starts abnormality determination for the boost power supply-using component after the recovery condition is satisfied when the boost circuit drive signal is turned on from off and the boost circuit starts to be driven. The boost power supply-using component is a resolver (15) that detects the rotational position of a motor (10),
3. The abnormality detection device according to claim 1, wherein the abnormality determination unit disables abnormality determination of the signal acquired from the resolver when driving of the boost circuit is stopped. The boost power supply component is a resolver excitation circuit (45) that outputs an excitation signal to a resolver (15) that detects the rotational position of a motor (10),
4. The abnormality detection device according to claim 1, wherein the abnormality determination unit disables abnormality determination of the voltage supplied to the resolver excitation circuit when driving of the boost circuit is stopped. The boost power supply component is a resolver excitation circuit (45) that outputs an excitation signal to a resolver (15) that detects the rotational position of a motor (10),
The abnormality detection device according to any one of claims 1 to 4, wherein the abnormality determination unit disables abnormality determination of the excitation periodic signal periodically output from the resolver excitation circuit when driving of the boost circuit is stopped. The boost power supply component is a gate drive circuit (47) that outputs a gate signal to an inverter element constituting an inverter (21) that converts the power of a motor (10),
The abnormality detection device according to any one of claims 1 to 5, wherein the abnormality determination unit disables abnormality determination of a signal related to inverter element information output from the gate drive circuit when driving of the boost circuit is stopped. The boost power supply-using component is a resolver (15) that detects the rotational position of a motor (10),
The abnormality detection device according to any one of claims 1 to 6, wherein the abnormality determination unit invalidates abnormality determination based on a comparison between an angle calculation value based on a signal obtained from the resolver and an angle calculation value obtained via a resolver digital converter (16) when driving of the boost circuit is stopped. A program for an abnormality detection device (30) that detects an abnormality related to a component that uses a boost power supply,
The abnormality detection device includes:
A boost circuit (31) for boosting the power from the battery (7);
an internal power supply (41, 42) for supplying power boosted by the boost circuit;
A boosted power supply component (15, 45, 47) that operates using power supplied from the internal power supply;
a control unit (50) having a drive signal generating unit (51) for generating a boost circuit drive signal for driving the boost circuit, and an abnormality determining unit (55) for determining an abnormality related to a component using a boost power supply;
Equipped with
a program for operating the abnormality determination unit to perform control so as to disable abnormality determination relating to the component using the boost power supply when the boost circuit is stopped by turning off the boost circuit drive signal ;

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