JP2021064996A - Rotary electric machine system - Google Patents

Abstract

To maintain a desired operation in a rotary electric machine system even in the case where an earth fault occurs in a power supply path in which power is supplied to a control section of an inverter.SOLUTION: A first inverter 36 drives a first rotary electric machine 37. A second inverter 46 drives a second rotary electric machine 47. A first control section 33 controls the first inverter 36. A second control section 43 controls the second inverter 46. A first power supply path 30 supplies power to the first control section 33. A second power supply path 40 supplies power to the second control section 43. A connection path 50 electrically connects the first power supply path 30 and the second power supply path 40 with each other. A ground fault determination section 63 determines the presence/absence of a ground fault factor indicating whether or not a ground fault occurs in the first power supply path 30 or the second power supply path 40 or a possibility of the occurrence. Cut-off sections 54 and 64 cut off the connection path 50 on a condition that the presence of a predetermined ground fault factor is determined.SELECTED DRAWING: Figure 1

Description

The present invention relates to a rotary electric machine system including a rotary electric machine and an inverter for controlling the rotary electric machine.

Some rotary electrical systems for vehicles are configured as follows. That is, it has a left rotary electric machine for driving the left tire and a right rotary electric machine for driving the right tire. Then, when one of the left and right rotary electric machines fails, the operating state is brought closer to the operating state of the left and right rotary electric machines without stopping the other left and right rotary electric machines. Then, as a document showing such a technique, there is the following Patent Document 1.

Japanese Patent No. 5784930

According to the above technique, even if one of the left and right rotating electric machines fails, the running can be maintained by the left and right rotating electric machines. However, there are some failures that cannot be dealt with by the above techniques. The present inventor has noticed that one of them is a ground fault in the power supply path that supplies power to the control unit of the inverter.

That is, power is supplied from the battery to the left control unit that controls the inverter of the rotary electric machine on the left side and the control unit on the right side that controls the inverter of the rotary electric machine on the right side. If a ground fault occurs in the power supply path, both the left and right control units will run out of power, and neither the left or right inverter can be controlled. As a result, neither the left or right inverter can drive the rotary electric machine, and the rotary electric machine system cannot maintain the running. And, such a problem is not limited to the case of traveling in a rotary electric machine system for a vehicle, but is the same in the case of a desired operation in another rotary electric machine system.

The present invention has been made in view of the above circumstances, and an object of the present invention is to be able to maintain a desired operation in a rotary electric machine system even when a ground fault occurs in a power supply path for supplying power to an inverter control unit. And.

The rotary electric machine system of the present invention includes a first inverter for driving a predetermined first rotary electric machine, a second inverter for driving a predetermined second rotary electric machine, a first control unit for controlling the first inverter, and the above. It has a second control unit that controls the second inverter. Further, a connection that electrically connects the first power supply path for supplying power to the first control unit, the second power supply path for supplying power to the second control unit, and the first power supply path and the second power supply path to each other. It has a route and. Further, with a ground fault determination unit that determines whether or not there is a ground fault element indicating that a ground fault has occurred or is likely to occur in the first power supply path or the second power supply path. It has a blocking unit that shuts off the connection path on condition that it is determined that the ground fault element for dealing with a predetermined blocking exists.

According to the present invention, since there is a connection path, each of the first control unit and the second control unit has a redundant configuration in which power can be supplied from both the first power supply path and the second power supply path. Then, the blocking unit cuts off the connection path on condition that it is determined that a predetermined ground fault element for dealing with the blocking exists. Therefore, when a ground fault occurs in one of the first power supply path and the second power supply path, the influence can be prevented from affecting the other power supply path.

Therefore, when a ground fault occurs in one of the power supply paths and one of the control units runs out of power, the control unit stops controlling one inverter, and the one inverter stops driving one rotary electric machine. Even in such a case, the control of the other inverter can be maintained for the other control unit, and the driving of the other rotary electric power by the inverter can be maintained. The output of the other rotary electric machine can be used to maintain the desired operation in the rotary electric machine system.

Circuit diagram showing the rotary electric machine system of the first embodiment Flowchart showing ground fault provisional diagnosis control Flowchart showing ground fault main diagnostic control A graph showing the transition between the voltage of the first control unit and the torque of the first rotary electric machine.

Next, an embodiment of the present invention will be described with reference to the drawings. However, the present invention is not limited to the embodiments, and can be appropriately modified and implemented without departing from the spirit of the invention.

[First Embodiment]
FIG. 1 is a circuit diagram showing the rotary electric machine system 80 of the first embodiment and its surroundings. The rotary electric machine system 80 is mounted on the vehicle 90 and has a high-voltage circuit Hc and a low-voltage circuit Lc. The high-voltage circuit Hc includes a high-voltage battery 10, a first inverter 36 and a first rotary electric machine 37, and a second inverter 46 and a second rotary electric machine 47. The high-voltage battery 10 is, for example, a lithium battery and has a plurality of cell batteries in series. The first rotating electric machine 37 drives the first tire 38 which is the front wheel on the left side of the vehicle 90, and the second rotating electric machine 47 drives the second tire 48 which is the front wheel on the right side of the vehicle 90.

First, the first inverter 36 and the first rotary electric machine 37 will be described. The first rotary electric machine 37 has a three-phase coil (not shown) and a rotor (not shown) that is rotationally driven by the three-phase coil. The rotor is connected to the shaft of the first tire 38 via a speed reducer (not shown) and rotates together with the first tire 38.

The first inverter 36 has three-phase wiring (not shown) for supplying power to the three-phase coil of the first rotary electric machine 37. Each phase of the three-phase wiring has an upper arm that is electrically connected to the positive terminal of the high-voltage battery 10 and a lower arm that is electrically connected to the negative terminal of the high-voltage battery 10. Semiconductor switches are provided on each of the three upper arms and each of the three lower arms. A total of six semiconductor switches are controlled by a first control unit 33, which will be described later.

The first inverter 36 drives the first rotary electric machine 37 by converting the electric power supplied from the high-voltage battery 10 into alternating current and supplying the electric power to the first rotary electric machine 37. Further, when the vehicle 90 is decelerated, the first inverter 36 converts the rotational energy of the rotor of the first rotating electric machine 37 rotated by the first tire 38 into electric power energy, and supplies power to the high-voltage battery 10 and the low-voltage battery 20. This charges these batteries 10 and 20. In this way, the first inverter 36 controls both power running and regeneration of the first rotary electric machine 37.

Next, the second inverter 46 and the second rotary electric machine 47 will be described. The description of the second inverter 46 and the second rotary electric machine 47 corresponds to the above description of the first inverter 36 and the first rotary electric machine 37, replacing "first" with "second" and corresponding to the reference numerals. It is the same as the one.

The low-voltage circuit Lc includes a transformer circuit 13, a low-voltage battery 20, a first control unit 33, a second control unit 43, and an upper control unit 60. The transformer circuit 13 includes a control unit for controlling the transformer circuit 13 itself, and operates when electric power is supplied to the control unit or the like. The transformer circuit 13 is, for example, a DCDC converter that lowers the voltage supplied from the high-voltage battery 10 during operation to supply power to a predetermined first power supply path 30. The low-voltage battery 20 is, for example, a lead battery and supplies power to a predetermined second power supply path 40.

A power storage device 23 for supplying power to the transformer circuit 13 and the first control unit 33 is electrically connected to the first power supply path 30. The power storage device 23 may be, for example, a capacitor, or various batteries such as a lithium battery and a lead battery. The first feeding path 30 is provided with a first voltmeter 32 for measuring the first feeding voltage V1, which is the difference between the predetermined reference potential and the potential of the first feeding path 30. The above reference potential is the ground potential of the vehicle body in this embodiment. The first control unit 33 is supplied with power from the first power supply path 30. The first control unit 33 controls the first inverter 36 by controlling the six semiconductor switches of the first inverter 36 and the like.

The second feeding path 40 is provided with a second voltmeter 42 for measuring the second feeding voltage V2, which is the difference between the above reference potential and the potential of the second feeding path 40. The second control unit 43 is supplied with power from the second power supply path 40. The second control unit 43 controls the second inverter 46 by controlling the six semiconductor switches of the second inverter 46 and the like.

The first power supply path 30 and the second power supply path 40 are electrically connected to each other via the connection path 50. The connection path 50 is provided with an ammeter 51, a voltmeter 52, and a connection switch 54. The ammeter 51 measures the connection path current Ic, which is the current flowing through the connection path 50. The voltmeter 52 measures the connection path voltage Vc, which is the difference between the above reference potential and the potential of the connection path 50. When the connection switch 54 is turned on, the connection path 50 can be energized, and when it is turned off, the connection path 50 cannot be energized.

In the following, an element indicating that a ground fault has occurred or may occur in the first power supply path 30 or the second power supply path 40 is referred to as a “ground fault element”. The connection switch 54 is normally turned on when the ground fault element is not confirmed. Therefore, normally, for each of the first control unit 33 and the second control unit 43, a redundant configuration capable of supplying power from both the first power supply path 30 and the second power supply path 40 is established.

Therefore, the power supply to the first control unit 33 can normally be performed not only from the transformer circuit 13 and the power storage device 23 but also from the low voltage battery 20. Further, the power supply to the second control unit 43 can normally be performed not only from the low-voltage battery 20 but also from the transformer circuit 13 and the power storage device 23. Further, the power supply to the control unit and the like of the transformer circuit 13 can be normally supplied not only from the power storage device 23 but also from the low voltage battery 20. Further, each power source of the high-voltage battery 10, the low-voltage battery 20, and the power storage device 23 can normally supply power to another power source to charge the other power source.

On the other hand, when the connection switch 54 is turned off, the power supply to the first control unit 33 is inevitably performed from the transformer circuit 13 or the power storage device 23, and the power supply to the second control unit 43 is inevitably performed. It will be started from the low voltage battery 20. Further, when the connection switch 54 is turned off, the power storage device 23 is inevitably charged by the electric power of the high-voltage battery 10. Further, when the connection switch 54 is turned off, the power supply to the control unit or the like of the transformer circuit 13 is inevitably performed from the power storage device 23.

The upper control unit 60 includes a ground fault determination unit 63, a cutoff processing unit 64, a torque control unit 65, and a yaw control unit 66. The connection path current Ic is input from the ammeter 51, the connection path voltage Vc is input from the voltmeter 52, and the connection path voltage Vc is input from the voltmeter 32 to the upper control unit 60 via each communication line (not shown). 1 The feed voltage V1 is input, and the second feed voltage V2 is input from the second voltmeter 42.

The upper control unit 60 may have a redundant configuration in which power is supplied from both the first power supply path 30 and the second power supply path 40 by, for example, electrical wiring (not shown), or the first power supply path 30 and the second power supply path 30 and the second power supply may be supplied. The power may be supplied from a third power supply path different from any of the paths 40. In short, the upper control unit 60 may maintain power supply to itself even when any one of the first power supply path 30 and the second power supply path 40 has a ground fault.

The ground fault determination unit 63 performs the ground fault provisional diagnosis X1 based on the connection path current Ic and the connection path voltage Vc, and the first feed voltage is provided on the condition that the ground fault provisional determination is performed in the ground fault temporary diagnosis X1. The ground fault main diagnosis X2 is performed based on V1 and the second feed voltage V2. The cutoff processing unit 64 turns off the connection switch 54 on condition that the ground fault is provisionally confirmed. The cutoff processing unit 64 and the connection switch 54 correspond to the "cutoff unit" in the present invention.

The torque control unit 65 performs a predetermined limit control Q in the high-voltage circuit Hc on the condition that the ground fault is provisionally determined in the above-mentioned ground fault provisional diagnosis X1 for the low-voltage circuit Lc. As a result, the increase in power supply from the high-voltage battery 10 to the inverters 36 and 46 is limited as compared with the case where the limit control Q is not performed. As a result, the increase in the torque output by the first rotary electric machine 37 and the increase in the torque output by the second rotary electric machine 47 are limited. The limit control Q may, for example, completely prohibit the increase in the power supply to the inverters 36 and 46, or increase the power supply to the inverters 36 and 46 as compared with the case where the limit control Q is not performed. May be kept small.

Further, the torque control unit 65 gradually reduces the power supply to the first inverter 36 in the high-voltage circuit Hc, provided that the ground fault is confirmed in the first power supply path 30 forming a part of the low-voltage circuit Lc. The first reduction control R1 is started. As a result, the torque output by the first rotary electric machine 37 is gradually reduced as compared with the case where the first reduction control R1 is not performed. Further, the torque control unit 65 gradually reduces the power supply to the second inverter 46 in the high-voltage circuit Hc, provided that the ground fault is confirmed in the second power supply path 40 forming a part of the low-voltage circuit Lc. The second reduction control R2 is started. As a result, the torque output by the second rotary electric machine 47 is gradually reduced as compared with the case where the second reduction control R2 is not performed.

When the yaw control unit 66 performs the predetermined yaw control Y when the reduction controls R1 and R2, which are either the first reduction control R1 or the second reduction control R2, are performed, the yaw control Y is not performed. In comparison with the above, the traveling direction of the vehicle 90 is suppressed from being shifted by the reduction controls R1 and R2. Further, the yaw control unit 66 is in a state where the first control unit 33 has stopped controlling the first inverter 36 due to a ground fault in the first power supply path 30, or the second control unit 66 has a ground fault in the second power supply path 40. By performing the yaw control Y in the state where the 43 stops the control of the second inverter 46, the traveling direction of the vehicle 90 shifts due to the stop of the control as compared with the case where the yaw control Y is not performed. Suppress.

Specifically, the yaw control Y can be controlled as follows, for example. That is, when a ground fault occurs in the first power feeding path 30 during power running, the output of the first rotating electric machine 37 that drives the tire on the left side decreases, so that the traveling direction of the vehicle 90 shifts to the left side. Further, even if a ground fault occurs in the second power feeding path 40 during regeneration, the amount of power generated by the second rotating electric machine 47 generated by the tire on the right side decreases, that is, the amount of braking decreases, so that the vehicle 90 advances. The direction shifts to the left. Under such a situation, in the yaw control Y, a force is applied to the side that turns the steering wheel to the right side to assist the side that turns the steering wheel to the right side.

On the other hand, contrary to the above, when a ground fault occurs in the second feeding path 40 during power running or when a ground fault occurs in the first feeding path 30 during regeneration, the yaw control Y moves the handle. Apply force to the side that cuts to the left and assist the side that turns the handle to the left.

Next, with reference to FIG. 2, the ground fault temporary diagnosis control including the ground fault temporary diagnosis X1 and the countermeasures associated with the result will be described. FIG. 2 is a flowchart showing the ground fault provisional diagnosis control.

In the ground fault temporary diagnosis control, first, the ground fault determination unit 63 performs the ground fault temporary diagnosis X1. Specifically, first, the ground fault determination unit 63 acquires the connection path current Ic from the ammeter 51 (S101). At this time, if the first power supply path 30 has a ground fault, a large current should be flowing from the second power supply path 40 side to the first power supply path 30 side. If the second power supply path 40 has a ground fault, a large current should be flowing from the first power supply path 30 side to the second power supply path 40 side. In that state, it is determined whether or not the absolute value of the connection path current Ic is larger than the predetermined current value Icth, that is, whether or not there is a ground fault element for provisional determination (S102).

When it is determined in S102 that the absolute value of the connection path current Ic is smaller than the predetermined current value Icth (S102: NO), it is assumed that the ground fault element is not confirmed from the connection path current Ic, and then the voltmeter 52 Acquire the connection path voltage Vc (S103). At this time, if either the first power supply path 30 or the second power supply path 40 has a ground fault, the connection path voltage Vc should be lower than in the normal state due to electric leakage. In that state, it is determined whether or not the connection path voltage Vc is lower than the predetermined voltage value Vcth, that is, whether or not there is a ground fault element for provisional determination (S104). When it is determined that the connection path voltage Vc is larger than the predetermined voltage value Vcth (S104: NO), it is assumed that the ground fault element is not confirmed from the connection path voltage Vc, and the ground fault provisional determination (S105) is not performed. The ground fault provisional diagnosis X1 and the ground fault provisional diagnosis control are terminated.

On the other hand, in S102, when it is determined that the absolute value of the connection path current Ic is larger than the predetermined current value Icth (S102: YES), or in S104, it is determined that the connection path voltage Vc is smaller than the predetermined voltage value Vcth (S102). In S104: YES), assuming that the ground fault element is confirmed, the ground fault provisional determination is performed (S105), and the ground fault provisional diagnosis X1 is terminated. After that, the connection switch 54 is turned off by the cutoff processing unit 64 (S106) to cut off the connection path 50, and the torque control unit 65 performs the limit control Q (S107) to start each of the high-voltage batteries 10. Limit the increase in power supply to the inverters 36 and 46. Then, the ground fault provisional diagnosis control is terminated.

Next, with reference to FIG. 3, the ground fault main diagnosis control including the ground fault main diagnosis X2 and the countermeasures associated with the result will be described. FIG. 3 is a flowchart showing the ground fault main diagnostic control. The ground fault main diagnosis control is started on condition that the ground fault provisional confirmation (S105) is made in the ground fault provisional diagnosis X1. Ground fault In this diagnosis X2, first, the ground fault determination unit 63 acquires the first feed voltage V1 from the first voltmeter 32 and the second feed voltage V2 from the second voltmeter 42 (S201).

At this time, if the first power supply path 30 has a ground fault, the first power supply voltage V1 should be lower than in the normal state due to electric leakage. Further, if the second feeding path 40 has a ground fault, the second feeding voltage V2 should be lower than the normal time due to the electric leakage. In that state, it is determined whether or not either the first feed voltage V1 or the second feed voltage V2 is lower than the predetermined threshold value Vth, that is, whether or not the ground fault element for final determination exists (S202). ). When it is determined that both the first feed voltage V1 and the second feed voltage V2 are higher than the predetermined threshold value Vth (S202: NO), it is assumed that the ground fault element for final confirmation is not confirmed, and the ground fault provisional confirmation is cancelled. (S203), the ground fault main diagnosis X2 and the ground fault main diagnosis control are terminated.

On the other hand, when it is determined in S202 that either the first feed voltage V1 or the second feed voltage V2 is lower than the predetermined threshold value Vth (S202: YES), it is assumed that the ground fault element for final determination is confirmed. The entanglement is confirmed (S204). Specifically, when it is determined that the first feed voltage V1 is lower than the predetermined threshold value Vth, the ground fault is finally determined for the first feed path 30. On the other hand, when it is determined that the second feeding voltage V2 is lower than the predetermined threshold value Vth, the ground fault main determination is performed for the second feeding path 40, and the ground fault main diagnosis X2 is terminated.

After that, the torque control unit 65 starts the reduction controls R1 and R2 (S205). Specifically, when the ground fault is confirmed for the first power supply path 30, the first reduction control R1 that gradually reduces the power supply to the first inverter 36 is started, and the ground fault for the second power supply path 40. When this confirmation is made, the second reduction control R2 that gradually reduces the power supply to the second inverter 46 is started.

Then, with the start of the reduction controls R1 and R2 (S205), the yaw control unit 66 starts the yaw control Y (S206). Then, the ground fault main diagnostic control is terminated. After the first reduction control R1 is completed, the transformer circuit 13 is stopped to stop the power supply from the high-voltage battery 10 to the first power supply path 30. As a result, it is possible to stop wasting the power of the high-voltage battery 10 due to the ground fault of the first power feeding path 30. Further, after the second reduction control R2 is completed, the power supply from the low voltage battery 20 to the second power supply path 40 is stopped. As a result, it is possible to stop wasting the power of the low voltage battery 20 due to the ground fault of the second power feeding path 40.

Next, the details of the first reduction control R1 performed in S205 will be described with reference to FIG. FIG. 4 is a graph showing the transition between the first feed voltage V1 and the torque output by the first rotary electric machine 37 when a ground fault occurs in the first feed path 30. Specifically, a ground fault occurs in the first power supply path 30 at a predetermined ground fault timing t0, a ground fault provisional confirmation (S105) is performed at the subsequent provisional confirmation timing t1, and the first at the subsequent final confirmation timing t2. The case where the ground fault is confirmed (S204) for the power supply path 30 is shown.

In this case, the torque control unit 65 stops the first control unit 33 from stopping the control of the first inverter 36 based on the time change of the first feed voltage V1 from immediately before the final confirmation timing t2 to the final confirmation timing t2. Find the timing t3. Specifically, from the slope θ of the first feed voltage V1 from immediately before the final confirmation timing t2 to the final confirmation timing t2, the timing at which the first feed voltage V1 falls below the predetermined minimum required voltage Vlimit is obtained, and the timing below that is determined. The stop timing t3 is set. The required minimum voltage Vlimit is the first feed voltage V1 required for the first control unit 33 to maintain the activated state. In the first reduction control R1, the power supply from the high-voltage battery 10 to the first inverter 36 is gradually reduced so that the torque output by the first rotary electric machine 37 becomes exactly zero at the stop timing t3.

In the figure, the interval from "t0" to "t1" or "t2" is shown sufficiently large for easy understanding, but in reality, the time from the ground fault timing t0 to the stop timing t3 is millisecond. Whereas the time is on the order of seconds (ms), the time from the ground fault timing t0 to the tentative confirmation timing t1 and the final confirmation timing t2 is on the order of microseconds (μs). Therefore, the time from the ground fault timing t0 to the stop timing t3 is sufficiently longer than the ground fault determination time. By utilizing the time until the stop timing t3, the torque of the first rotary electric machine 37 can be gradually reduced in this way.

The description of the details of the second reduction control R2 performed in S205 includes the above description of the details of the first reduction control R1, the "first" being read as "second", and the reference numerals being replaced with the corresponding ones. The same applies to the description of the figure.

According to this embodiment, the following problems can be solved. If the voltage of both the first feed voltage V1 and the second feed voltage V2 drops due to a ground fault, the first control unit 33 cannot control the first inverter 36, and the second control unit 43 cannot control the second inverter. 46 cannot be controlled. Therefore, all of the six semiconductor switches of the first inverter 36 and the six semiconductor switches of the second inverter 46 are fixed in the OFF state or the like. Therefore, it becomes impossible to drive the first rotary electric machine 37 by the first inverter 36 and the second rotary electric machine 47 by the second inverter 46, and it becomes impossible to maintain the running of the vehicle 90. It ends up.

In that respect, in the present embodiment, the connection path 50 is blocked on the condition that the ground fault is provisionally confirmed. Therefore, when a ground fault occurs in the first power supply path 30, the influence can be prevented from affecting the second power supply path 40, and when a ground fault occurs in the second power supply path 40, the effect can be prevented. The influence can be prevented from reaching the first power feeding path 30.

Therefore, a ground fault occurs in the first power supply path 30 and the first control unit 33 runs out of power, so that the first control unit 33 stops the control of the first inverter 36, and the first inverter 36 stops the control. Even when the drive of the 1-rotary electric machine 37 is stopped, the second control unit 43 can maintain the control of the 2nd inverter 46 and maintain the drive of the 2nd rotary electric machine 47 by the 2nd inverter 46. .. The running can be maintained by the output of the second rotary electric machine 47. Similarly, even when a ground fault occurs in the second power feeding path 40, the driving of the first rotating electric machine 37 by the first inverter 36 can be maintained, and the running is maintained by the output of the first rotating electric machine 37. can do. Therefore, even if a ground fault occurs in either the first power supply path 30 or the second power supply path 40, the running of the vehicle 90 can be maintained.

In addition, the following problems can be solved. When a ground fault occurs in the first power feeding path 30, there is a high possibility that the ground fault will cause the first control unit 33 to run out of power and stop the control of the first inverter 36. Then, when the first control unit 33 suddenly stops controlling the first inverter 36 while the first inverter 36 is driving the first rotary electric machine 37 with a large output, the first inverter 36 suddenly stops. Stops driving the first rotary electric machine 37. Since the first rotary electric machine 37 drives the tire on the left side, the traveling direction of the vehicle 90 may suddenly change significantly to the left side.

In that respect, in the present embodiment, by performing the first reduction control R1 on the condition that the ground fault is finally determined for the first power supply path 30, the first rotary electric machine is compared with the case where the first reduction control R1 is not performed. The torque output by 37 is gradually reduced. Therefore, before the first control unit 33 stops the control of the first inverter 36, the output of the first rotary electric machine 37 may be gradually reduced in advance to make the drive stop of the first rotary electric machine 37 as gentle as possible. it can. Therefore, it is possible to prevent the traveling direction of the vehicle 90 from suddenly changing significantly to the left side.

Similarly, by performing the second reduction control R2 on the condition that the ground fault is finally determined for the second power supply path 40, the torque output by the second rotary electric machine 47 is compared with the case where the second reduction control R2 is not performed. Gradually decrease. Therefore, it is possible to prevent the traveling direction of the vehicle 90 from suddenly changing to the right side.

In addition, the following effects can be obtained. The blocking processing unit 64 shuts off the connection path 50 on condition that the ground fault is temporarily determined. Therefore, when the possibility of a ground fault is detected, the respective power supply paths 30 and 40 are quickly made independent so that the influence of the ground fault of one power supply path 30 and 40 does not reach the other power supply paths 40 and 30. Can be. On the other hand, the torque control unit 65 performs reduction controls R1 and R2 on condition that the ground fault is finally confirmed after the ground fault is provisionally confirmed. Therefore, it is possible to avoid the harmful effect of starting the reduction controls R1 and R2 due to an erroneous temporary ground fault determination different from the final ground fault. As described above, it is possible to achieve both the early independence of the power feeding paths 30 and 40 and the careful start of the reduction controls R1 and R2.

Further, the torque control unit 65 performs the limit control Q on the condition that the ground fault is temporarily determined, and starts the reduction controls R1 and R2 on the condition that the ground fault is finally confirmed. In this way, at the stage of provisionally determining the ground fault in which it is uncertain whether or not the ground fault has actually occurred, the increase in torque is limited by the limit control Q, and at the stage of final determination of the ground fault, the decrease control R1 By starting the torque reduction with R2, it is possible to achieve both an early response and a careful start of the reduction controls R1 and R2.

Further, when the torque control unit 65 performs the first reduction control R1, the torque control unit 65 predicts the time from the time change of the first feed voltage V1 until the first control unit 33 stops the control of the first inverter 36. The first reduction control R1 is performed based on the time. Therefore, by reducing the power supply to the first inverter 36 as slowly as possible within the time range until the control is stopped, the influence of the drive reduction of the first rotary electric machine 37 on the traveling direction of the vehicle 90 is as gentle as possible. It can be suppressed. Similarly, in the second reduction control R2, the power supply to the second inverter 46 is reduced as slowly as possible within the time until the second control unit 43 stops the control of the second inverter 46. , The influence of the drive reduction of the second rotary electric machine 47 on the traveling direction of the vehicle 90 can be suppressed as gently as possible.

Further, by performing the yaw control Y when the reduction controls R1 and R2 are performed, the traveling direction of the vehicle 90 is suppressed from being shifted by the reduction controls R1 and R2, so that the vehicle 90 can be stabilized. Further, even when the control of the first control unit 33 or the second control unit 43 is stopped due to a ground fault, the yaw control Y is performed to prevent the traveling direction of the vehicle 90 from shifting due to the stop of the control. Therefore, the vehicle 90 can be stabilized even after the control is stopped.

Further, since it has a transformer circuit 13 that transforms the electric power of the high-voltage battery 10 and supplies power to the first power supply path 30, and a low-voltage battery 20 that supplies power to the second power supply path 40, each power supply path 30 has a simple configuration. Each of the 40 can be powered from a separate power source.

In addition, the following effects can be obtained. When a ground fault occurs in the first power supply path 30, a large current flows from the second power supply path 40 to the first power supply path 30 via the connection path 50. On the other hand, when a ground fault occurs in the second power supply path 40, a large current flows from the first power supply path 30 to the second power supply path 40 via the connection path 50. In that respect, in the present embodiment, the ground fault provisional determination is performed on the condition that the absolute value of the connection path current Ic is larger than the predetermined current value Icth (S102: YES). Therefore, with a simple configuration, it is possible to detect that any one of the first power supply path 30 and the second power supply path 40 has a ground fault.

In addition, the following effects can be obtained. If either the first power supply path 30 or the second power supply path 40 has a ground fault, the connection path voltage Vc becomes lower than usual due to electric leakage. In that respect, in the present embodiment, the ground fault provisional determination is performed on the condition that the connection path voltage Vc is lower than the predetermined voltage value Vct (S104: YES). Therefore, with a simple configuration, it is possible to detect that any one of the first power supply path 30 and the second power supply path 40 has a ground fault.

In addition, the following effects can be obtained. If the first power supply path 30 has a ground fault, the first power supply voltage V1 becomes lower than in the normal state due to electric leakage. Further, if the second feeding path 40 has a ground fault, the second feeding voltage V2 becomes lower than in the normal state due to electric leakage. In that respect, in the present embodiment, on the condition that the first feed voltage V1 is lower than the predetermined threshold value Vth (S202: YES), the ground fault is finally determined for the first feed path 30, and the second feed voltage V2 is predetermined. On condition that it is lower than the threshold value Vth (S202: YES), the ground fault is finally determined for the second power feeding path 40. Therefore, the ground fault of each of the feeding paths 30 and 40 can be detected with a simple configuration.

[Other Embodiments]
The above embodiment can be modified and implemented as follows. For example, instead of driving the left front wheel with the first rotating electric machine 37 and driving the right front wheel with the second rotating electric machine 47, the left rear wheel is driven by the first rotating electric machine 37 and the right rear wheel. May be driven by the second rotary electric machine 47. Further, for example, both the left and right front wheels may be driven by the first rotary electric machine 37, and both the left and right rear wheels may be driven by the second rotary electric machine 47. Further, for example, two diagonal tires of the front left and the rear right are driven by the first rotary electric machine 37, and two diagonal tires of the front right and the rear left are driven by the second rotary electric machine 47. You may do so.

Further, for example, the rotary electric machine system 80 may drive not the vehicle 90 but another moving body such as a drone or a flying car. Even in this case, for example, when the drone or the flying car has four propellers of front left, front right, rear left, and rear right, the two propellers on one diagonal of the front left and the rear right are rotated for the first time. It can be driven by the electric machine 37, and the two diagonal propellers, the front right and the rear left, can be driven by the second rotating electric machine 47.

Further, for example, the torque control unit 65 may be eliminated, and in the event of a ground fault, only the connection path 50 may be cut off, and the reduction controls R1 and R2 may not be performed. Further, for example, the ground fault provisional diagnosis X1 may be eliminated and only the ground fault main diagnosis X2 may be performed. Then, the connection path 50 may be blocked on the condition that the ground fault is finally confirmed instead of the ground fault provisional confirmation. Further, for example, the limit control Q may not be performed, and only the reduction controls R1 and R2 may be performed. Further, for example, the yaw control unit 66 may be eliminated so that the yaw control Y may not be performed.

Further, for example, instead of the transformer circuit 13, a third battery that supplies power to the first power supply path 30 may be provided. Further, for example, one of the ammeter 51 and the voltmeter 52 may be eliminated, and the ground fault provisional diagnosis X1 may be performed based on only one of the connection path current Ic and the connection path voltage Vc.

Further, for example, on the condition that the absolute value of the connection path current Ic is larger than the predetermined current value Icth, there is a possibility of a ground fault in either the first power supply path 30 or the second power supply path 40. Instead of performing the entanglement provisional determination, the following may be performed. That is, on the condition that the current flowing through the connection path 50 from the second power supply path 40 side to the first power supply path 30 side is larger than the predetermined current value Icth, the ground fault provisional determination is performed for the first power supply path 30. You may. Then, on the condition that the current flowing through the connection path 50 from the first power supply path 30 side to the second power supply path 40 side is larger than the predetermined current value Icth, the ground fault provisional determination is performed for the second power supply path 40. You may.

Further, for example, in this case, the first reduction control R1 is started on the condition that the above-mentioned ground fault provisional determination is made for the first power supply path 30, and the second reduction control R2 is for the second power supply path 40. It may be started on the condition that the above-mentioned provisional ground fault is confirmed. Then, it may be canceled on the condition that the provisional ground fault is canceled.

Further, for example, the first power supply path 30 is provided on the condition that the current flowing from the transformer circuit 13 to the first power supply path 30 is larger than a predetermined value in a state where the first voltmeter 32 is eliminated and the connection path 50 is cut off. The ground fault may be confirmed. Further, for example, the second power supply path 40 is provided on the condition that the current flowing from the low voltage battery 20 to the second power supply path 40 is larger than a predetermined value in a state where the second voltmeter 42 is eliminated and the connection path 50 is cut off. The ground fault may be confirmed.

Further, for example, in the first reduction control R1, instead of gradually reducing the power supply to the first inverter 36, the first rotary electric machine is controlled by controlling each of the six semiconductor switches (duty control, etc.) of the first inverter 36. The torque output by the 37 may be gradually reduced. Similarly, in the second reduction control R2, instead of gradually reducing the power supply to the second inverter 46, the second rotation is performed by controlling each of the six semiconductor switches (duty control, etc.) of the second inverter 46. The torque output by the electric machine 47 may be gradually reduced.

Further, for example, in the limit control Q, instead of limiting the increase in power supply to the first inverter 36 and the second inverter 46, control of each semiconductor switch of the first inverter 36 and the second inverter 46 (duty control, etc.) Therefore, the increase in the torque output by the first rotary electric machine 37 and the second rotary electric machine 47 may be limited.

Further, for example, in FIG. 1, the first voltmeter 32 measures the voltage of a predetermined portion of the first feeding path 30 as the first feeding voltage V1, but instead of this, the voltage between terminals of the transformer circuit 13 ( The output voltage), the voltage between the terminals of the first control unit 33 (input voltage), and the voltage of the junk box to which the first control unit 33 is connected may be measured as the first feed voltage V1. .. Further, for example, in FIG. 1, the second voltmeter 42 measures the voltage of a predetermined portion of the second feeding path 40 as the second feeding voltage V2, but instead of this, the voltage between the terminals of the low voltage battery 20 ( The output voltage), the voltage between the terminals of the second control unit 43 (input voltage), and the voltage of the junk box to which the second control unit 43 is connected may be measured as the second feed voltage V2. ..

30 ... 1st power supply path, 33 ... 1st control unit, 36 ... 1st inverter, 37 ... 1st rotary electric machine, 40 ... 2nd power supply path, 43 ... 2nd control unit, 46 ... 2nd inverter, 47 ... 2 rotary electric machine, 50 ... connection path, 54 ... connection switch, 63 ... ground fault determination unit, 64 ... cutoff processing unit, 80 ... rotary electric machine system.

Claims (11)

A first inverter (36) for driving a predetermined first rotary electric machine (37) and
A second inverter (46) for driving a predetermined second rotary electric machine (47) and
The first control unit (33) that controls the first inverter and
A second control unit (43) that controls the second inverter, and
The first power supply path (30) for supplying power to the first control unit and
A second power supply path (40) for supplying power to the second control unit,
A connection path (50) that electrically connects the first power supply path and the second power supply path to each other, and
A ground fault determination unit (63) for determining whether or not there is a ground fault element indicating that a ground fault has occurred or is likely to occur in the first power supply path or the second power supply path. When,
A blocking unit (54,64) that cuts off the connection path on condition that it is determined that the ground fault element for dealing with a predetermined blocking exists.
Rotating electric machine system (80). The torque control unit has a predetermined torque control unit (65), and the torque control unit has a predetermined first feeding path on the condition that it is determined that the ground fault element for the predetermined first countermeasure is present in the first power feeding path. By performing the reduction control (R1), the torque output by the first rotary electric machine is gradually reduced as compared with the case where the first reduction control is not performed, and the second power feeding path is used for a predetermined second countermeasure. By performing the predetermined second reduction control (R2) on the condition that it is determined that the ground fault element is present, the second rotary electric machine outputs the output as compared with the case where the second reduction control is not performed. Gradually reduce the torque
The rotary electric machine system according to claim 1. The ground fault element for dealing with blocking is the ground fault element for provisional determination, and the ground fault elements for the first countermeasure and the second countermeasure are the ground fault elements for final determination. ,
The ground fault determination unit determines whether or not the ground fault element for final determination is present, on condition that the ground fault element for provisional determination is present.
The rotary electric machine system according to claim 2. The torque control unit performs the predetermined limit control (Q) on the condition that the ground fault element for provisional determination is determined to exist, as compared with the case where the limit control is not performed. The rotary electric machine system according to claim 3, which limits an increase in torque output by the first rotary electric machine and an increase in torque output by the second rotary electric machine. When the torque control unit performs the first reduction control, the time from the time change of the voltage (V1) of the first power supply path until the first control unit stops the control of the first inverter. When the first reduction control is performed based on the time and the second reduction control is performed, the second control unit performs the first reduction control based on the time change of the voltage (V2) of the second power feeding path. The time until the control of the second inverter is stopped is predicted, and the second reduction control is performed based on the time.
The rotary electric machine system according to any one of claims 2 to 4. The first rotary electric machine drives one of the left and right tires of the vehicle, and the second rotary electric machine drives the other left and right tire of the vehicle.
It has a yaw control unit (66) that controls the traveling direction of the vehicle, and the yaw control unit has a predetermined yaw control (Y) when the reduction control of the first reduction control or the second reduction control is performed. The rotary electric machine system according to any one of claims 2 to 5, wherein the traveling direction is suppressed from being shifted by the reduction control as compared with the case where the yaw control is not performed. The first rotary electric machine drives one of the left and right tires of the vehicle, and the second rotary electric machine drives the other left and right tire of the vehicle.
The yaw control unit (66) that controls the traveling direction of the vehicle is provided, and the yaw control unit has the yaw control unit stopped controlling the first inverter due to a ground fault in the first power supply path. The yaw control is not performed by performing the predetermined yaw control (Y) in the state or the state in which the second control unit stops the control of the second inverter due to the ground fault of the second power feeding path. The rotary electric system according to any one of claims 1 to 6, wherein the traveling direction is suppressed from being shifted due to the stop of the control as compared with the case. A first battery (10) that supplies power to the first inverter and the second inverter, a transformer circuit (13) that transforms the power of the first battery to supply power to the first power supply path, and the second power supply path. The rotary electric system according to any one of claims 1 to 7, further comprising a second battery (20) for supplying power to the The ground fault element for dealing with interruption according to any one of claims 1 to 8, wherein the absolute value of the current (Ic) flowing in the connection path is larger than the predetermined current value (Icth). Rotating electric system. Claims 1 to 1, wherein the ground fault element for dealing with the interruption includes that the connection path voltage (Vc), which is the difference between the predetermined reference potential and the potential of the connection path, is lower than the predetermined voltage value (Vcth). The rotary electric machine system according to any one of 9. The ground fault element for the first countermeasure is that the first feed voltage (V1), which is the difference between the predetermined reference potential and the potential of the first feed path, is lower than the predetermined threshold (Vth).
The ground fault element for the second countermeasure is that the second feed voltage (V2), which is the difference between the reference potential and the potential of the second feed path, is lower than the predetermined threshold value.
The rotary electric machine system according to any one of claims 2 to 6.

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