Control device for rotary electrical machine, program, and method for controlling rotary electrical machine

Abstract

A control device (70) comprises: a setting unit (95) that sets Y drive control or H drive control as a control mode for a first inverter (20) and a second inverter (30); and a switch control unit (96) that controls the first inverter and the second inverter on the basis of the set control mode. The control device comprises a determination unit (97) that determines whether a wheel (220RL, 220RR, 210FL, 210FR) is in a slipping situation during traveling of a vehicle (200). When the determination unit determines the presence of the slipping situation, the setting unit switches between the Y drive control and the H drive control from the currently set control mode to the other control mode.

Description

Rotating electric machine control device, program, and rotating electric machine control method CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Japanese Application No. 2024-012324, filed on January 30, 2024, the contents of which are incorporated herein by reference.

[0002] The present disclosure relates to a control device for a rotating electric machine, a program, and a control method for a rotating electric machine.

[0003] Conventionally, a system for controlling the drive of a rotating electric machine using two inverters has been known. In this system, a first inverter is electrically connected to first ends of a multi-phase armature winding of the rotating electric machine, and a second inverter is electrically connected to second ends of the armature winding. The drive of the rotating electric machine is controlled by switching control of the first and second inverters. An example of such a technology is disclosed in Patent Document 1.

[0004] Japanese Patent Application Laid-Open No. 2017-175747

[0005] The above system may be installed in a vehicle. In this case, it is desirable to control the first and second inverters so as to minimize the loss of vehicle running stability.

[0006] A primary object of the present disclosure is to provide a control device, a program, and a control method for a rotating electric machine that can minimize the impairment of vehicle running stability.

[0007] The present disclosure relates to a control device for a rotating electric machine that is applied to a system including: a rotating electric machine having a multi-phase armature winding; a first inverter having first upper arm switches and first lower arm switches connected in series for the same number of phases, and a series connection of the first upper arm switches and the first lower arm switches connected in parallel to a DC power source; a second inverter having second upper arm switches and second lower arm switches connected in series for the same number of phases; a positive side bus bar that electrically connects, in each phase, a high potential side terminal of the first upper arm switch and a high potential side terminal of the second upper arm switch; a negative side bus bar that electrically connects, in each phase, a low potential side terminal of the first lower arm switch and a low potential side terminal of the second lower arm switch; and a changeover switch provided on a target bus bar that is at least one of the positive side bus bar and the negative side bus bar, wherein the system is provided on a vehicle and configured so that a rotational force of a rotor of the rotating electric machine is transmitted to wheels of the vehicle, In each phase, the low potential side terminal of the first upper arm switch and the high potential side terminal of the first lower arm switch are electrically connected to a first end of the armature winding, and in each phase, the low potential side terminal of the second upper arm switch and the high potential side terminal of the second lower arm switch are electrically connected to a second end of the armature winding, and when the changeover switch is turned on, it electrically connects the first inverter and the second inverter via the target bus, and when turned off, it cuts off the electrical connection between the first inverter and the second inverter via the target bus.

[0008] The present disclosure comprises a setting unit that sets Y drive control or H drive control as the control mode of the first inverter and the second inverter; and a switch control unit that controls the on or off of the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch based on the set control mode, wherein the Y drive control is control that fixes the second upper arm switch of each phase on and fixes the second lower arm switch of each phase off when the changeover switch is off, or fixes the second lower arm switch of each phase on and fixes the second upper arm switch of each phase off when the changeover switch is off, and turns the first upper arm switch and the first lower arm switch on and off; and the H drive control is control that turns the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch on and off.

[0009] The present disclosure includes a determination unit that determines whether or not the wheels are in a state where they will slip while the vehicle is traveling, and when the determination unit determines that the wheels are in a state where they will slip, the setting unit switches from one of the currently set control modes of the Y drive control and the H drive control to the other control mode.

[0010] According to the present disclosure, it is possible to minimize the impairment of vehicle running stability.

[0011] The present disclosure can be embodied, for example, as follows: When the setting unit determines that the vehicle is in a slipping situation while the H drive control is set, the setting unit switches the control mode from the H drive control to the Y drive control.

[0012] The present disclosure can be embodied, for example, as follows: the determination unit determines whether one of the left and right wheels of the vehicle is in a slipping state, and the setting unit switches the control mode from the Y drive control to the H drive control when it is determined that the wheel is in a slipping state while the Y drive control is set.

[0013] The above and other objects, features, and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which Fig. 1 is a schematic diagram of a vehicle according to a first embodiment, Fig. 2 is an overall configuration diagram of a control system, Fig. 3 is a functional block diagram of control processing executed by a motor ECU, Fig. 4 is a diagram showing a control aspect of Y drive control, Fig. 5 is a diagram showing a control aspect of H drive control, Fig. 6 is a diagram showing control map information, Fig. 7 is a flowchart of processing executed by the motor ECU, Fig. 8 is a schematic diagram of a vehicle according to a second embodiment, Fig. 9 is a flowchart of processing executed by the motor ECU, Fig. 10 is a schematic diagram of a vehicle according to a third embodiment, Fig. 11 is a flowchart of processing executed by the motor ECU, Fig. 12 is a schematic diagram of a vehicle according to a fourth embodiment, Fig. 13 is a flowchart of processing executed by the motor ECU, Fig. 14 is an overall configuration diagram of a control system according to other embodiments, and Fig. 15 is a diagram showing a control aspect of Y drive control according to other embodiments.

[0014] Several embodiments will be described with reference to the drawings. In several embodiments, functionally and / or structurally corresponding and / or associated parts may be designated by the same reference numerals or reference numerals that differ in the hundredth or more digit. For corresponding and / or associated parts, reference may be made to the descriptions of other embodiments.

[0015] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First Embodiment A first embodiment of a control device according to the present disclosure will now be described with reference to the drawings. The control device of this embodiment is applied to an electric vehicle.

[0016] 1, the vehicle 200 includes a vehicle body 201 and wheels, which are a left front wheel 210FL, a right front wheel 210FR, a left rear wheel 220RL, and a right rear wheel 220RR.

[0017] The vehicle 200 is equipped with a rotating electric machine 40 that serves as a driving power source. The rotating electric machine 40 of this embodiment is an onboard motor provided on the vehicle body 201. Furthermore, the rotational force of the rotating electric machine 40 of this embodiment is transmitted to a left rear wheel 220RL and a right rear wheel 220RR. That is, the left rear wheel 220RL and the right rear wheel 220RR are rotationally driven by the common rotating electric machine 40. The left rear wheel 220RL and the right rear wheel 220RR are driving wheels, and the left front wheel 210FL and the right front wheel 210FR are driven wheels.

[0018] The vehicle 200 is equipped with a mechanical brake device 230. The brake device 230 is provided corresponding to each of the wheels 210FL, 210FR, 220RL, and 220RR, and is a device that generates a braking force by applying a frictional force to the wheel.

[0019] As shown in Figures 1 and 2, a vehicle 200 includes a control system 100 that performs various driving controls, etc. The control system 100 includes a battery 10, which is a DC power source, a first inverter 20, a second inverter 30, and the rotating electric machine 40. The battery 10 is, for example, a battery pack including a series connection of unit cells. The unit cell is a single battery cell or a series connection of multiple battery cells. The battery cell is, for example, a secondary battery such as a lithium-ion battery.

[0020] The first inverter 20 and the second inverter 30 are power conversion circuits that convert DC power supplied from the battery 10 into three-phase AC power and supply it to the rotating electric machine 40 .

[0021] The first inverter 20 includes a series connection of U-, V-, and W-phase first upper arm switches SUHa, SVHa, and SWHa and U-, V-, and W-phase first lower arm switches SULa, SVLa, and SWLa. The second inverter 30 includes a series connection of U-, V-, and W-phase second upper arm switches SUHb, SVHb, and SWHb and U-, V-, and W-phase second lower arm switches SULb, SVLb, and SWLb.

[0022] In this embodiment, each of the switches SUHa to SWLa and SUHb to SWLb is a voltage-controlled semiconductor switching element, more specifically, an IGBT. In this case, the high-potential terminal of each of the switches SUHa to SWLa and SUHb to SWLb is the collector, and the low-potential terminal is the emitter. A freewheel diode is connected in anti-parallel to each of the switches SUHa to SWLb. Specifically, U-, V-, and W-phase first upper-arm diodes DUHa, DVHa, and DWHa are connected in anti-parallel to the U-, V-, and W-phase first upper-arm switches SUHa, SVHa, and SWHa, respectively, and U-, V-, and W-phase first lower-arm diodes DULa, DVLa, and DWLa are connected in anti-parallel to the U-, V-, and W-phase first lower-arm switches SULa, SVLa, and SWLa, respectively. U, V, W-phase second upper-arm diodes DUHb, DVHb, DWHb are connected in anti-parallel to the U, V, W-phase second upper-arm switches SUHb, SVHb, SWHb, and U, V, W-phase second lower-arm diodes DULb, DVLb, DWLb are connected in anti-parallel to the U, V, W-phase second lower-arm switches SULb, SVLb, SWLb.

[0023] The collectors of the first upper arm switches SUHa, SVHa, SWHa for each phase and the collectors of the second upper arm switches SUHb, SVHb, SWHb for each phase are connected via a positive bus 11, which is an electrical path such as a bus bar. The emitters of the first lower arm switches SULa, SVLa, SWLa for each phase and the emitters of the second lower arm switches SULb, SVLb, SWLb for each phase are connected via a negative bus 12, which is an electrical path such as a bus bar. The emitters of the second lower arm switches SULb, SVLb, SWLb for each phase are connected to the negative bus 12.

[0024] The control system 100 includes a power switch 14. The power switch 14 is, for example, a semiconductor switching element or a mechanical relay. The power switch 14 connects the positive bus 11 and the positive terminal of the battery 10. When the power switch 14 is turned on, the positive terminal of the battery 10 is electrically connected to the collectors of the first upper arm switches SUHa, SVHa, and SWHa of each phase. When the power switch 14 is turned off, the positive terminal of the battery 10 is electrically disconnected from the collectors of the first upper arm switches SUHa, SVHa, and SWHa of each phase.

[0025] The control system 100 includes a capacitor 15. The capacitor 15 functions as a smoothing capacitor. The capacitor 15 is connected in parallel to the series-connected body of the first upper arm switches SUHa to SWHa of each phase and the first lower arm switches SULa to SWLa of each phase.

[0026] The rotating electric machine 40 includes a rotor 41 and a stator 50. The rotor 41 is capable of transmitting power to the left rear wheel 220RL and the right rear wheel 220RR. In this embodiment, the rotating electric machine 40 is a permanent magnet field type synchronous machine. The rotor 41 includes permanent magnets 42 (e.g., neodymium magnets) as field poles.

[0027] The stator 50 includes a U-phase winding 51U, a V-phase winding 51V, and a W-phase winding 51W as armature windings. The phase windings 51U, 51V, and 51W are arranged at intervals of 120 electrical degrees on the stator core that constitutes the stator 50. The phase windings 51U, 51V, and 51W are open windings.

[0028] In each phase, the emitters of first upper switches SUHa, SVHa, SWHa and the collectors of first lower switches SULa, SVLa, SWLa are connected to first ends 51Ua, 51Va, 51Wa of the windings 51U, 51V, 51W, respectively. In each phase, the emitters of second upper switches SUHb, SVHb, SWHb and the collectors of second lower switches SULb, SVLb, SWLb are connected to second ends 51Ub, 51Vb, 51Wb of the windings 51U, 51V, 51W, respectively.

[0029] The control system 100 includes a changeover switch QH and a diode DH. The changeover switch QH is provided on the positive bus 11 (corresponding to the "target bus"). The changeover switch QH is, for example, a semiconductor switching element or a mechanical relay. In this embodiment, the changeover switch QH is an IGBT. The collector of the changeover switch QH is connected to the first inverter 20 side, and the emitter of the changeover switch QH is connected to the second inverter 30 side. A diode DH is connected in antiparallel to the changeover switch QH.

[0030] When the changeover switch QH is turned on, it electrically connects the collectors of the upper phase arm switches SUHa, SVHa, SWHa of the first inverter 20 to the collectors of the upper phase arm switches SUHb, SVHb, SWHb of the second inverter 30. On the other hand, when the changeover switch QH is turned off, it electrically disconnects the collectors of the upper phase arm switches SUHa, SVHa, SWHa of the first inverter 20 from the collectors of the upper phase arm switches SUHb, SVHb, SWHb of the second inverter 30.

[0031] The control system 100 includes a current sensor 60, a rotation angle sensor 61, and a voltage sensor 62. The current sensor 60 detects the phase current flowing through each of the phase windings 51U, 51V, and 51W. In this embodiment, the current sensor 60 is provided on one of both ends of each of the phase windings 51U, 51V, and 51W that is closer to the first inverter 20. Note that the current sensor 60 may also be provided on one of both ends of each of the phase windings 51U, 51V, and 51W that is closer to the second inverter 30.

[0032] The rotation angle sensor 61 is, for example, a resolver, and detects the electrical angle of the rotor 41. The voltage sensor 62 detects the voltage between the terminals of the capacitor 15.

[0033] The control system 100 includes a vehicle speed sensor 63, a wheel speed sensor 64, an outside air temperature sensor 65, and a navigation device 66. The vehicle speed sensor 63 detects the traveling speed of the vehicle 200. The wheel speed sensor 64 detects the rotation speed of each wheel. The outside air temperature sensor 65 detects the outside air temperature around the vehicle 200.

[0034] Map information including road information is stored in a memory unit (e.g., storage) of the navigation device 66. The navigation device 66 receives current position information of the vehicle 200 detected by a GPS sensor (not shown) provided in the control system 100 and weather information.

[0035] The control system 100 includes a motor ECU 70 and a host ECU 80. The motor ECU 70 receives detection values ​​from a current sensor 60, a rotation angle sensor 61, and a voltage sensor 62. The host ECU 80 receives detection values ​​from a vehicle speed sensor 63, a wheel speed sensor 64, and an outside air temperature sensor 65, as well as information from a navigation device 66. The motor ECU 70 and the host ECU 80 are configured to be able to communicate information acquired by them with each other. The host ECU 80 is configured to be able to communicate with the navigation device 66.

[0036] The motor ECU 70 is an electronic control unit that controls the rotating electric machine 40. The motor ECU 70 includes a processor 71 and a storage unit 72 as hardware components. In the motor ECU 70, the processor 71 and the storage unit 72 are connected to each other via a communication bus 73.

[0037] The memory unit 72 includes a memory and a storage as hardware. The memory is a storage device for storing data used in the processing of the motor ECU 70. The memory provides the processor 71 with a working area for temporary use when the processor 71 performs processing, for example. The memory includes, for example, a ROM or a RAM. The storage is a storage device for storing various programs and data to be read and executed by the processor 71, and is a non-transitory tangible storage medium. The storage includes, for example, an HDD or a flash memory. The storage stores program information and the like for the processing shown in FIGS. 3 and 7, which will be described later.

[0038] The host ECU 80 is an electronic control unit that controls the running of the vehicle 200, such as controlling the brake device 230. Similar to the motor ECU 70, the host ECU 80 includes a processor 81 and a storage unit 82 as hardware. In the host ECU 80, the processor 81 and the storage unit 82 are connected to each other via a communication bus 83.

[0039] For example, program information stored on a non-transient physical recording medium is installed in the storage units 72 and 82. The recording medium is, for example, a USB memory, a CD-ROM, or a DVD. Also, for example, program information transmitted via a communication network, such as over the air (OTA), is installed in the storage units 72 and 82.

[0040] FIG. 3 is a block diagram showing the control process of the rotary electric machine 40 executed by the motor ECU 70. As shown in FIG.

[0041] The command value calculation unit 90 calculates a d-axis current command value Id* and a q-axis current command value Iq* in the dq coordinate system based on the command torque Trq* received from the host ECU 80 .

[0042] The two-phase conversion unit 91 calculates the d-axis current value Idr and the q-axis current value Iqr based on the phase currents Iur, Ivr, and Iwr detected by the current sensor 60 and the electrical angle θr detected by the rotation angle sensor 61.

[0043] The current feedback unit 92 calculates a d-axis voltage command value Vd* and a q-axis voltage command value Vq* based on the d- and q-axis current command values ​​Id* and Iq* and the d- and q-axis current values ​​Idr and Iqr. Specifically, the current feedback unit 92 calculates a d-axis current deviation, which is the difference between the d-axis current command value Id* and the d-axis current value Idr, and calculates a d-axis voltage command value Vd* as a manipulated variable for feedback-controlling the calculated d-axis current deviation to zero. The current feedback unit 92 calculates a q-axis current deviation, which is the difference between the q-axis current command value Iq* and the q-axis current value Iqr, and calculates a q-axis voltage command value Vq* as a manipulated variable for feedback-controlling the calculated q-axis current deviation to zero. The feedback control is, for example, proportional-plus-integral control.

[0044] The three-phase converter 93 calculates U-, V-, and W-phase voltage command values ​​Vu*, Vv*, and Vw* based on the d- and q-axis voltage command values ​​Vd*, Vq* and the electrical angle θr. The U-, V-, and W-phase voltage command values ​​Vu*, Vv*, and Vw* are command values ​​for the voltages applied to the U-, V-, and W-phase windings 51U, 51V, and 51W.

[0045] The speed calculation unit 94 calculates the rotation speed Nr of the rotor 41 based on the electrical angle θr.

[0046] The setting unit 95 generates drive signals for the switches SUHa to SWLa and SUHb to SWLb of the first and second inverters 20 and 30. The drive signals are made up of on and off commands for the switches.

[0047] Specifically, the setting unit 95 calculates U-, V-, and W-phase normalized command values ​​Dutyu, Dutyv, and Dutyw by normalizing the U-, V-, and W-phase voltage command values ​​Vu*, Vv*, and Vw* by the power supply voltage Vsr, which is the detection voltage of the voltage sensor 62. Specifically, the U-, V-, and W-phase normalized command values ​​Dutyu, Dutyv, and Dutyw are values ​​obtained by dividing the U-, V-, and W-phase voltage command values ​​Vu*, Vv*, and Vw* by 1 / 2 of the power supply voltage Vsr.

[0048] The setting unit 95 selects whether the drive state of the control system 100 should be Y drive control or H drive control. In the present embodiment, the setting unit 95 selects whether the drive state should be Y drive control or H drive control based on the operating point of the rotating electric machine 40, which is determined by the calculated rotation speed Nr and command torque Trq*, and on the control map information. As shown in FIG. 6 , the control map information is information that defines the Y drive control region and the H drive control region in association with the rotation speed Nr and the command torque Trq*. The control map information is stored in the storage unit 72.

[0049] 6 shows control map information according to this embodiment. The control map information defines an operating region of the rotating electrical machine 40, bounded by the first maximum torque line Ltmax1, the second maximum torque line Ltmax2, the first line L1, the second line L2, the axis of the rotational speed Nr (hereinafter referred to as the horizontal axis), and the axis of the command torque Trq* (hereinafter referred to as the vertical axis). The first and second maximum torque lines Ltmax1 and Ltmax2 define the maximum torque Tmax, which is the maximum value of the command torque Trq*, and extend along the horizontal axis (specifically, extend parallel to the horizontal axis). The first maximum torque line Ltmax1 is a line extending from the vertical axis. The second maximum torque line Ltmax2 is a line extending from one end of the first maximum torque line Ltmax1 along the horizontal axis (specifically, extend parallel to the horizontal axis).

[0050] The first line L1 extends from one end of the second maximum torque line Ltmax2 and decreases in value on the vertical axis as the rotational speed Nr increases. The second line L2 extends along the vertical axis from one end of the first line L1 to the horizontal axis (specifically, extends parallel to the vertical axis). The value on the horizontal axis of the second line L2 is the maximum rotational speed Nmax, which is the maximum value of the rotational speed Nr.

[0051] The judgment threshold Jth is made up of a first threshold line J1 and a second threshold line J2. The first threshold line J1 is a line extending along the first line L1 from the boundary between the first maximum torque line Ltmax1 and the second maximum torque line Ltmax2. The first threshold line J1 is a line extending such that the value on the vertical axis decreases as the rotation speed Nr increases. The second threshold line J2 is a line extending from one end of the first threshold line J1 along the second line L2 (specifically, extending parallel to the second line L2). The value on the horizontal axis of the second threshold line J2 is a judgment speed Nth (>0) that is lower than the maximum rotation speed Nmax.

[0052] The region of the operating range where the rotation speed Nr is equal to or less than the judgment threshold Jth is the Y drive control region, while the region of the operating range where the rotation speed Nr exceeds the judgment threshold Jth is the H drive control region.

[0053] The setting unit 95 selects Y drive control when it determines that the operating point determined from the command torque Trq* and the rotation speed Nr is in the Y drive control region, whereas the setting unit 85 selects H drive control when it determines that the operating point is in the H drive control region.

[0054] When Y-drive control is selected, the setting unit 95 turns off the selector switch QH and performs PWM drive of the switches SUHa to SWLa of the first inverter 20 as Y-drive control, as shown in Fig. 4. The setting unit 95 also fixes the upper arm switches SUHb, SVHb, and SWHb of the second inverter 30 to on, and fixes the lower arm switches SULb, SVLb, and SWLb of the second inverter 30 to off. As a result, the phase windings 51U, 51V, and 51W are star-connected via the second inverter 30.

[0055] The setting unit 95 generates drive signals for the switches SUHa to SWLa of the first inverter 20 based on a magnitude comparison between the U-, V-, and W-phase normalized command values ​​Dutyu, Dutyv, and Dutyw and the carrier signal Sgc. The carrier signal Sgc is, for example, a triangular wave signal whose gradual increase and decrease rates are equal.

[0056] On the other hand, when the setting unit 95 selects the H drive control, as shown in FIG. 5, the setting unit 95 turns on the changeover switch QH, PWM-drives each of the switches SUHa to SWLa of the first inverter 20, and PWM-drives each of the switches SUHb to SWLb of the second inverter 30.

[0057] Specifically, the setting unit 95 generates drive signals for the switches SUHa-SWLa of the first inverter 20 based on a magnitude comparison between the U-, V-, and W-phase normalized command values ​​Dutyu, Dutyv, and Dutyw and the first carrier signal Sg1, similar to the Y-drive control. The setting unit 95 generates drive signals for the switches SUHb-SWLb of the second inverter 30 based on a magnitude comparison between the U-, V-, and W-phase normalized command values ​​Dutyu, Dutyv, and Dutyw and the second carrier signal Sg2, similar to the Y-drive control. The first and second carrier signals Sg1 and Sg2 are, for example, triangular wave signals with equal increasing and decreasing speeds. The frequency, amplitude, and fluctuation center value of the second carrier signal Sg2 are the same as those of the first carrier signal Sg1. The phase difference between the first carrier signal Sg1 and the second carrier signal Sg2 is 180°. In this embodiment, the frequency of the carrier signals Sg1 and Sg2 used in the H drive control is the same as the frequency of the carrier signal Sgc used in the Y drive control.

[0058] Based on the generated drive signal, the switch control unit 96 controls the charge / discharge current of the gates of the switches SUHa-SWLa and SUHb-SWLb of the first and second inverters 20 and 30. As a result, the switches SUHa-SWLa and SUHb-SWLb of the first and second inverters 20 and 30 are controlled to be turned on or off in accordance with the drive signal.

[0059] The switching patterns of the switches of the inverters 20, 30, which are switched in accordance with the drive signal in the H drive control, are shifted in phase by 120° in electrical angle in each phase. Also, the switching pattern of the switches of the first inverter 20, which is switched in accordance with the drive signal in the Y drive control, is shifted in phase by 120° in electrical angle in each phase.

[0060] The maximum value of the torque generated by the rotary electric machine 40 is greater when H drive control is performed than when Y drive control is performed. This is because the maximum value of the voltage applied across the armature winding is higher when H drive control is performed than when Y drive control is performed. In a situation where the drive wheels of the vehicle 200 slip, it is necessary to appropriately select Y drive control or H drive control to minimize the loss of driving stability of the vehicle 200.

[0061] Therefore, the motor ECU 70 includes a determination unit 97. The determination unit 97 determines whether or not the drive wheels 220 are in a slipping state while the vehicle 200 is traveling. In this embodiment, the determination unit 97 calculates the slip ratio of the drive wheels and determines whether or not a slipping state is occurring based on the calculated slip ratio. The slip ratio in this embodiment is expressed by the following equation (eq1):

[0062] In the above equation (eq1), Vlc is the traveling speed Vlc of the vehicle 200 detected by the vehicle speed sensor 63. Vlt is the peripheral speed of the drive wheels. The determination unit 97 may calculate the peripheral speed based on the rotation speed of the drive wheels detected by the wheel speed sensor 64.

[0063] If the determination unit 97 determines that the slip ratio exceeds the threshold value, it determines that a situation in which slip will occur exists, and if the determination unit 97 determines that the slip ratio is equal to or less than the threshold value, it determines that a situation in which slip will not occur exists. Specifically, for example, if the determination unit 97 determines that the higher of the slip ratios of the left rear wheel 220RL and the right rear wheel 220RR exceeds the threshold value, it determines that a situation in which slip will occur exists.

[0064] Note that the determination unit 97 may determine that the road surface on which the vehicle 200 is traveling is a low μ road if it determines that the road surface is prone to slippage. Here, the determination unit 97 may determine that the road surface is a low μ road if it determines that the outside air temperature detected by the outside air temperature sensor 65 is equal to or lower than a determination temperature, for example. The determination temperature may be set to a temperature at which the road surface on which the vehicle 200 is traveling is expected to freeze, specifically, a temperature below freezing. Furthermore, the determination unit 97 may determine that the road surface is a low μ road if it determines that the weather around the vehicle 200 is raining or snowing based on weather information received by the navigation device 66, for example.

[0065] When the determination unit 97 determines that a situation in which slip would occur if the currently set control mode were H drive control, the setting unit 95 switches the control mode to Y drive control and prohibits the execution of H drive control. This reduces at least one of the rotation speed and torque of the drive wheels, making it difficult for slip to occur and minimizing impairment of the running stability of the vehicle 200.

[0066] A flowchart of the control mode switching process is shown in Fig. 7. The process shown in Fig. 7 is repeatedly executed by the processor 71 included in the motor ECU 70 at a predetermined control cycle, for example.

[0067] In step S10, the setting unit 95 determines whether the current operating point is in the H drive control region or the Y drive control region.

[0068] If it is determined in step S10 that the operating point is in the Y drive control region, the process proceeds to step S11, where the setting unit 95 selects the Y drive control.

[0069] On the other hand, if it is determined in step S10 that the operating point is in the H drive control range, the process proceeds to step S12. In step S12, the determination unit 97 determines whether or not a slip situation exists. If it is determined in step S12 that a slip situation does not exist, the process proceeds to step S13, where the setting unit 95 selects H drive control.

[0070] On the other hand, if it is determined in step S12 that a slip situation exists, the process proceeds to step S14, where the setting unit 95 selects Y drive control instead of H drive control. By performing the process of step S14 while H drive control is being performed, for example, in the operating region of FIG. 6, the operating point existing in the H drive control region moves along the horizontal axis to the Y drive control region. As a result, the occurrence of slip can be suppressed, and the driving stability of the vehicle 200 can be prevented from being impaired as much as possible.

[0071] Second Embodiment A second embodiment will be described below with reference to the drawings, focusing on differences from the first embodiment. In this embodiment, as shown in Fig. 8, a vehicle 200 is provided with a rotating electric machine that rotates the front wheels and a rotating electric machine that rotates the rear wheels. In other words, the vehicle 200 is an electric four-wheel drive vehicle.

[0072] More specifically, the control system 100 includes a front rotating electric machine 40F and a rear rotating electric machine 40R. The configuration of each of the rotating electric machines 40F, 40R is similar to the configuration of the rotating electric machine 40 of the first embodiment.

[0073] The control system 100 includes a first inverter 20F and a second inverter 30F corresponding to the front rotating electric machine 40F, and a first inverter 20R and a second inverter 30R corresponding to the rear rotating electric machine 40R. Each of the first inverters 20F, 20R has the same configuration as the first inverter 20 of the first embodiment. Furthermore, each of the second inverters 30F, 30R has the same configuration as the second inverter 30 of the first embodiment.

[0074] A first end of the armature winding of the front rotating electric machine 40F is connected to the battery 10 via the first inverter 20F. A second end of the armature winding of the front rotating electric machine 40F is connected to the second inverter 30F. A first end of the armature winding of the rear rotating electric machine 40R is connected to the battery 10 via the first inverter 20R. A second end of the armature winding of the rear rotating electric machine 40R is connected to the second inverter 30R.

[0075] Vehicle 200 is configured so that the rotational force of the rotor of front rotating electric machine 40F is transmitted to left front wheel 210FL and right front wheel 210FR, and the rotational force of the rotor of rear rotating electric machine 40R is transmitted to left rear wheel 220RL and right rear wheel 220RR.

[0076] A flowchart of the control mode switching process is shown in Fig. 9. The process shown in Fig. 9 is repeatedly executed by the processor 71, for example, at a predetermined control cycle.

[0077] In step S20, the setting unit 95 determines whether the current operating point is in the H drive control region or the Y drive control region.

[0078] If it is determined in step S20 that the operating point is in the Y drive control region, the process proceeds to step S21, where the setting unit 95 selects Y drive control as the front control mode and the rear control mode. The front control mode is the control mode of the first and second inverters 20F, 30F corresponding to the front rotating electric machine 40F. The rear control mode is the control mode of the first and second inverters 20R, 30R corresponding to the rear rotating electric machine 40R.

[0079] On the other hand, if it is determined in step S20 that the operating point is in the H drive control region, the process proceeds to step S22. In step S22, the determination unit 97 determines whether or not the front wheels are in a slipping state. Specifically, if the determination unit 97 determines that the value obtained by subtracting the rear wheel rotation speed Vr detected by the wheel speed sensor 64 from the front wheel rotation speed Vf detected by the wheel speed sensor 64 (hereinafter referred to as the rotation speed difference ΔV) exceeds the speed threshold, the determination unit 97 determines that the front wheels are in a slipping state. On the other hand, if the determination unit 97 determines that the rotation speed difference ΔV is equal to or less than the speed threshold, the determination unit 97 determines that the front wheels are not in a slipping state. Here, the front wheel rotation speed Vf may be, for example, the higher of the rotation speeds of the left front wheel 210FL and the right front wheel 210FR detected by the wheel speed sensor 64, or the average value of the rotation speeds of the left front wheel 210FL and the right front wheel 210FR. The rear wheel rotation speed Vr may be, for example, the higher of the rotation speeds of the left rear wheel 220RL and the right rear wheel 220RR detected by the wheel speed sensor 64, or the average value of the rotation speeds of the left rear wheel 220RL and the right rear wheel 220RR.

[0080] If it is determined in step S22 that the front wheels are not in a state where they will slip, the process proceeds to step S23, where the setting unit 95 selects H drive control as the front control mode and rear control mode.

[0081] On the other hand, if it is determined in step S22 that the front wheels are in a slipping state, the process proceeds to step S24, where the setting unit 95 selects Y drive control instead of H drive control as the front control mode and rear control mode. This reduces the torque of the rotating electric machine 40, suppresses the occurrence of slippage, and minimizes the loss of running stability of the vehicle 200.

[0082] Furthermore, since slip determination is performed on the front wheels, it is possible to determine as early as possible that a slip situation is occurring and switch to Y drive control.

[0083] <Modification of Second Embodiment> The determination unit 97 may determine that the front wheels are slipping when it determines that the value obtained by subtracting the slip ratio of the rear wheels from the slip ratio of the front wheels (hereinafter referred to as the slip ratio difference) exceeds a threshold value for the slip ratio difference, instead of the rotational speed difference ΔV.

[0084] Third Embodiment Hereinafter, a third embodiment will be described with reference to the drawings, focusing on differences from the first embodiment. In this embodiment, as shown in Fig. 10 , the rotational force of a rotor 41 included in a rotating electric machine 40 is transmitted to a left front wheel 210FL and a right front wheel 210FR via an open-type differential gear device 250 that does not limit differential movement between the left and right wheels.

[0085] The differential gear device 250 includes a pinion shaft 252, a pair of pinion gears (not shown) journaled on the pinion shaft 252, side gears (not shown) meshed with the pinion gears, and left and right drive shafts 251L, 251R mechanically connected to the side gears. The pinion shaft 252 extends in the vehicle length direction of the vehicle 200. The drive shafts 251L, 251R extend in the vehicle width direction of the vehicle 200.

[0086] A rotor 41 is mechanically connected to the pinion shaft 252. A left front wheel 210FL is mechanically connected to the left drive shaft 251L, and a right front wheel 210FR is mechanically connected to the right drive shaft 251R. As a result, the rotational force of the rotor 41 is transmitted to the left front wheel 210FL and the right front wheel 210FR via the differential gear device 250.

[0087] A flowchart of the control mode switching process is shown in Fig. 11. The process shown in Fig. 11 is repeatedly executed by the processor 71, for example, at a predetermined control cycle.

[0088] In step S30, the setting unit 95 determines whether the current operating point is in the H drive control region or the Y drive control region.

[0089] If it is determined in step S30 that the operating point is in the H drive control region, the process proceeds to step S31, where the setting unit 95 selects H drive control.

[0090] On the other hand, if it is determined in step S30 that the operating point is in the Y drive control region, the process proceeds to step S32. In step S32, the determination unit 97 determines whether one of the left front wheel 210FL and the right front wheel 210FR is in a state where it will slip. This determination process is, for example, a process for determining whether the vehicle 200 is traveling on a split μ road. A split μ road is a road surface on which one of the left and right wheels has a relatively low coefficient of friction and the other has a relatively high coefficient of friction.

[0091] When the determination unit 97 determines that the absolute value of the speed difference, which is the difference between the rotation speed VL of the left front wheel 210FL detected by the wheel speed sensor 64 and the rotation speed VR of the right front wheel 210FR detected by the wheel speed sensor 64, exceeds the speed threshold Vth, the determination unit 97 determines that one of the left front wheel 210FL and the right front wheel 210FR is in a state where it will slip. On the other hand, when the determination unit 97 determines that the absolute value of the speed difference is equal to or less than the speed threshold Vth, the determination unit 97 determines that neither the left front wheel 210FL nor the right front wheel 210FR is in a state where it will slip.

[0092] If it is determined in step S32 that the vehicle is not in a slipping state, the process proceeds to step S33, where the setting unit 95 selects Y drive control.

[0093] On the other hand, if it is determined in step S32 that a slip situation exists, the process proceeds to step S34, where the setting section 95 selects H drive control instead of Y drive control.

[0094] In this embodiment, when the host ECU 80 determines that the absolute value of the difference between the rotation speed VL of the left front wheel 210FL and the rotation speed VR of the right front wheel 210FR exceeds a predetermined threshold (for example, a speed threshold Vth), the host ECU 80 performs brake LSD (Limited Slip Differential) control. This control applies a braking force by the brake device 230 to the wheel having the higher rotation speed out of the left front wheel 210FL and the right front wheel 210FR, in order to reduce the absolute value of the difference.

[0095] In a situation where slippage occurs on one of left front wheel 210FL and right front wheel 210FR, brake LSD control is performed, thereby increasing the torque distributed from differential gear device 250 to the wheel that is not slipping. In this case, H drive control is performed, which further increases the torque of the wheel that is not slipping, thereby minimizing impairment of the driving stability of vehicle 200.

[0096] <Modification of Third Embodiment> The host ECU 80 does not need to perform brake LSD control.

[0097] Fourth Embodiment A fourth embodiment will be described below with reference to the drawings, focusing on differences from the first embodiment. In this embodiment, as shown in Fig. 12, a vehicle 200 is provided with a left rotating electric machine 40LL that rotates a left front wheel 210FL and a right rotating electric machine 40RR that rotates a right front wheel 210FR. The configuration of each rotating electric machine 40RR, 40LL is similar to the configuration of the rotating electric machine 40 of the first embodiment.

[0098] The control system 100 includes a first inverter 20LL and a second inverter 30LL corresponding to the left rotating electric machine 40LL, and a first inverter 20RR and a second inverter 30RR corresponding to the right rotating electric machine 40RR. Each of the first inverters 20LL, 20RR has the same configuration as the first inverter 20 of the first embodiment. Furthermore, each of the second inverters 30LL, 30RR has the same configuration as the second inverter 30 of the first embodiment.

[0099] A first end of the armature winding of the left rotating electric machine 40LL is connected to the battery 10 via the first inverter 20LL. A second end of the armature winding of the left rotating electric machine 40LL is connected to the second inverter 30LL. A first end of the armature winding of the right rotating electric machine 40RR is connected to the battery 10 via the first inverter 20RR. A second end of the armature winding of the right rotating electric machine 40RR is connected to the second inverter 30RR.

[0100] Vehicle 200 is configured so that the rotational force of the rotor of left rotating electric machine 40LL is transmitted to left front wheel 210FL, and the rotational force of the rotor of right rotating electric machine 40RR is transmitted to right front wheel 210FR.

[0101] A flowchart of the control mode switching process is shown in Fig. 13. The process shown in Fig. 13 is repeatedly executed by the processor 71, for example, at a predetermined control cycle.

[0102] In step S40, the setting unit 95 determines whether the current operating point is in the H drive control region or the Y drive control region.

[0103] If it is determined in step S40 that the operating point is in the Y drive control region, the process proceeds to step S41, where the determination unit 97 determines whether or not one of the left front wheel 210FL and the right front wheel 210FR is in a state where it will slip. This determination process is a process for determining, for example, whether or not the vehicle 200 is traveling on a split μ road.

[0104] When the determination unit 97 determines that a first speed difference, which is a value obtained by subtracting the rotation speed VR of the right front wheel 210FR detected by the wheel speed sensor 64 from the rotation speed VL of the left front wheel 210FL detected by the wheel speed sensor 64, exceeds the speed threshold Vth, the determination unit 97 determines that a situation exists in which the left front wheel 210FL of the left front wheel 210FL and the right front wheel 210FR is likely to slip. On the other hand, when the determination unit 97 determines that a second speed difference, which is a value obtained by subtracting the rotation speed VL of the left front wheel 210FL from the rotation speed VR of the right front wheel 210FR, exceeds the speed threshold Vth, the determination unit 97 determines that a situation exists in which the right front wheel 210FR of the left front wheel 210FL and the right front wheel 210FR is likely to slip. On the other hand, if the judgment unit 97 determines that the absolute value of the difference between the rotation speed VL of the left front wheel 210FL and the rotation speed VR of the right front wheel 210FR is less than or equal to the speed threshold Vth, it determines that the left front wheel 210FL and the right front wheel 210FR are not in a situation where they will slip.

[0105] If it is determined in step S41 that a slip situation does not occur, the process proceeds to step S42, where the setting unit 95 selects Y-drive control as the left control mode and the right control mode. The left control mode is a control mode for the first and second inverters 20LL, 30LL corresponding to the left rotating electric machine 40LL. The right control mode is a control mode for the first and second inverters 20RR, 30RR corresponding to the right rotating electric machine 40RR.

[0106] On the other hand, if it is determined in step S41 that the left front wheel 210FL is in a state where it will slip, Y drive control is selected as the left side control mode and H drive control is selected as the right side control mode.

[0107] When the left and right control modes are set to Y drive control and it is determined in step S41 that the left front wheel 210FL is slipping, the right control mode is switched to H drive control. This makes it possible to increase the torque of the right front wheel 210FR, which is not slipping, and minimize the loss of driving stability of the vehicle 200.

[0108] On the other hand, when the left and right control modes are set to Y drive control and it is determined in step S41 that the right front wheel 210FR is slipping, the left control mode is switched to H drive control, which increases the torque of the left front wheel 210FL, which is not slipping, and minimizes the loss of driving stability of the vehicle 200.

[0109] If it is determined in step S40 that the operating point is in the H drive control region, the process proceeds to step S44, and the determination unit 97 determines whether one of the left front wheel 210FL and the right front wheel 210FR is in a slipping state using a method similar to that of step S41.

[0110] If it is determined in step S44 that the vehicle is not in a slipping state, the process proceeds to step S45, where the setting unit 95 selects H drive control as the left and right control modes.

[0111] On the other hand, if it is determined in step S44 that the left front wheel 210FL is in a state where it will slip, Y drive control is selected as the left side control mode and H drive control is selected as the right side control mode.

[0112] When the left side control mode and the right side control mode are set to H drive control, if it is determined in step S44 that the left front wheel 210FL is in a state where it will slip, the left side control mode is switched to Y drive control. This makes it possible to reduce the torque of the left front wheel 210FL where slip occurs, and to minimize impairment of the running stability of the vehicle 200.

[0113] On the other hand, when the left and right control modes are set to H drive control and it is determined in step S44 that the right front wheel 210FR is in a state where it is slipping, the right control mode is switched to Y drive control, which reduces the torque of the right front wheel 210FR where slipping occurs, thereby minimizing the loss of driving stability of the vehicle 200.

[0114] Other Embodiments The above-described embodiments may be modified as follows.

[0115] As shown in Fig. 14, the control system 100 may include a second changeover switch QL in addition to the first changeover switch QH. The second changeover switch QL is provided on the negative bus 12 (corresponding to the "target bus"). The second changeover switch QL is, for example, a semiconductor switching element or a mechanical relay. In this embodiment, the second changeover switch QL is an IGBT. A freewheel diode DL is connected in anti-parallel to the second changeover switch QL. The collector of the second changeover switch QL is connected to the second inverter 30 side, and the emitter of the second changeover switch QL is connected to the first inverter 20 side.

[0116] When the second changeover switch QL is turned on, it electrically connects the emitters of the lower phase arm switches SULa, SVLa, SWLa of the first inverter 20 to the emitters of the lower phase arm switches SULb, SVLb, SWLb of the second inverter 30. When the second changeover switch QL is turned off, it electrically disconnects the emitters of the lower phase arm switches SULa, SVLa, SWLa of the first inverter 20 from the emitters of the lower phase arm switches SULb, SVLb, SWLb of the second inverter 30.

[0117] When the motor ECU 70 selects the H drive control, it turns on the first changeover switch QH and the second changeover switch QL. On the other hand, when the motor ECU 70 selects the Y drive control, it turns off the first changeover switch QH and the second changeover switch QL.

[0118] In the Y-drive control, the motor ECU 70 may fix the upper arm switches SUHb, SVHb, and SWHb of the second inverter 30 to OFF and fix the lower arm switches SULb, SVLb, and SWLb of the second inverter 30 to ON, as shown in FIG. 15 . In this case, the lower arm side of the second inverter 30 functions as the neutral point. Incidentally, the configuration shown in FIG. 14 does not necessarily require the first changeover switch QH and the diode DH. In this case, the high-potential side terminals of the upper arm switches of the first and second inverters 20 and 30 are constantly connected to the positive bus 11.

[0119] The rotating electric machine is not limited to an on-board motor provided on the vehicle body, and may be an in-wheel motor.

[0120] In the above embodiments, the carrier signal is not limited to a triangular wave signal, and may be, for example, a sawtooth wave signal.

[0121] In each of the above embodiments, the motor ECU 70 may perform PWM driving based on space vector modulation instead of PWM driving based on a magnitude comparison between the command value and the carrier signal.

[0122] The DC power source is not limited to a battery, and may be, for example, a fuel cell.

[0123] The rotating electric machine is not limited to a permanent magnet field type synchronous machine, and may be, for example, an induction machine.

[0124] The rotating electric machine is not limited to a three-phase one, but may be a two-phase one or a four-phase or more phase one.

[0125] The semiconductor switches constituting the first inverter and the second inverter are not limited to IGBTs, but may be, for example, N-channel MOSFETs. In this case, the high-potential terminal of the switch is the drain, and the low-potential terminal is the source. Each switch also has a body diode.

[0126] The control unit and method described herein may be implemented by a special-purpose computer configured by configuring a processor and memory programmed to perform one or more functions embodied in a computer program. Alternatively, the control unit and method described herein may be implemented by a special-purpose computer configured by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the control unit and method described herein may be implemented by one or more special-purpose computers configured by combining a processor and memory programmed to perform one or more functions with a processor configured with one or more hardware logic circuits. Furthermore, the computer program may be stored in a computer-readable non-transitory tangible recording medium as instructions executed by a computer.

[0127] Although the present disclosure has been described with reference to the embodiments, it is understood that the present disclosure is not limited to the embodiments or structures. The present disclosure also encompasses various modifications and equivalent modifications. In addition, various combinations and forms, including only one element, more than one element, or less than one element, are also within the scope and spirit of the present disclosure.

Claims

1. A rotating electric machine (40) having a multi-phase armature winding (51U to 51W); a first inverter (20) having first upper arm switches (SUHa to SWHa) and first lower arm switches (SULa to SWLa) connected in series for the number of phases, the series-connected first upper arm switches and the first lower arm switches being connected in parallel to a DC power source (10); a second inverter (30) having second upper arm switches (SUHb to SWHb) and second lower arm switches (SULb to SWLb) connected in series for the number of phases; a positive bus (11) electrically connecting a high potential side terminal of the first upper arm switch and a high potential side terminal of the second upper arm switch in each phase; and a negative bus (12) electrically connecting a low potential side terminal of the first lower arm switch and a low potential side terminal of the second lower arm switch in each phase. a changeover switch (QH, QL) provided on a target busbar that is at least one of the positive busbar and the negative busbar, the control device (70) for a rotating electric machine applied to a system including the system, the system being provided on a vehicle (200), and configured to control a rotational force of a rotor (41) of the rotating electric machine to rotate wheels (220RL, 220RR, 210FL,210FR), in each phase, a low potential side terminal of the first upper arm switch and a high potential side terminal of the first lower arm switch are electrically connected to first ends (51Ua to 51Wa) of the armature windings, in each phase, a low potential side terminal of the second upper arm switch and a high potential side terminal of the second lower arm switch are electrically connected to second ends (51Ub to 51Wb) of the armature windings, the changeover switch electrically connects the first inverter and the second inverter via the target bus when turned on, and cuts off the electrical connection between the first inverter and the second inverter via the target bus when turned off, a setting unit (95) that sets Y-drive control or H-drive control as the control mode of the first inverter and the second inverter, and a switch control unit (96) that controls the on or off of the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch based on the set control mode, The Y drive control is a control for fixing the second upper arm switch of each phase on and fixing the second lower arm switch of each phase off when the changeover switch is off, or for fixing the second lower arm switch of each phase on and fixing the second upper arm switch of each phase off when the changeover switch is off, and for turning the first upper arm switch and the first lower arm switch on and off, and the H drive control is a control for turning the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch on and off, and the control device for a rotating electric machine includes a determination unit (97) that determines whether or not the wheels are in a slipping state while the vehicle is traveling, and the setting unit switches from one control mode currently set between the Y drive control and the H drive control to the other control mode when the determination unit determines that the wheels are in a slipping state.

2. The control device for a rotating electric machine according to claim 1, wherein the setting unit switches the control mode from the H drive control to the Y drive control when it is determined that the slip situation occurs when the H drive control is set.

3. The system is provided with a front rotating electric machine (40F) and a rear rotating electric machine (40R) as the rotating electric machines, the system is provided with the first inverter (20F) and the second inverter (30F) corresponding to the front rotating electric machine, and the first inverter (20R) and the second inverter (30R) corresponding to the rear rotating electric machine, the system is configured so that the rotational force of the rotor of the front rotating electric machine is transmitted to front wheels (210FL, 210FR) of the vehicle and the rotational force of the rotor of the rear rotating electric machine is transmitted to rear wheels (220RL, 220RR) of the vehicle, the determination unit determines whether or not the front wheels are in a slipping state, 3. The control device for a rotating electric machine according to claim 2, wherein the setting unit switches the front control mode and the rear control mode to the Y drive control when the determination unit determines that the front wheels are in a slipping state when the H drive control is set to a front control mode, which is the control mode of the first inverter and the second inverter corresponding to the front rotating electric machine, and a rear control mode, which is the control mode of the first inverter and the second inverter corresponding to the rear rotating electric machine.

4. A control device for a rotating electric machine as described in claim 1, wherein the judgment unit judges whether or not one of the left wheel (210FL) and the right wheel (210FR) of the vehicle is in a state where it will slip, and the setting unit switches the control mode from the Y drive control to the H drive control if it is determined that the slip situation exists when the Y drive control is set.

5. The control device for a rotating electric machine according to claim 4, wherein the vehicle is provided with an open type differential gear device (250) that transmits the rotational force of the rotor to the left wheel and the right wheel.

6. The system is provided with a left rotating electric machine (40LL) and a right rotating electric machine (40RR) as the rotating electric machines, the system is provided with the first inverter (20LL) and the second inverter (30LL) corresponding to the left rotating electric machine, and the first inverter (20RR) and the second inverter (30RR) corresponding to the right rotating electric machine, the system is configured so that the rotational force of the rotor of the left rotating electric machine is transmitted to the left wheel (210FL) of the vehicle, and the rotational force of the rotor of the right rotating electric machine is transmitted to the right wheel (210FR) of the vehicle, the setting unit, when a left control mode which is a control mode of the first inverter and the second inverter corresponding to the left rotating electric machine and a right control mode which is a control mode of the first inverter and the second inverter corresponding to the right rotating electric machine are set to the Y drive control, and when the determination unit determines that the left wheel is in a slipping situation, switches the right control mode to the H drive control, 5. The control device for a rotating electric machine according to claim 4, wherein, when the left side control mode and the right side control mode are set to the Y drive control, if the determination unit determines that the right wheel is in a slipping state, the left side control mode is switched to the H drive control.

7. A control device for a rotating electric machine as described in claim 6, wherein the setting unit switches the left side control mode to the Y drive control when the judgment unit judges that the left wheel is in a slipping state while the left side control mode and the right side control mode are set to the H drive control, and switches the right side control mode to the Y drive control when the judgment unit judges that the right wheel is in a slipping state while the left side control mode and the right side control mode are set to the H drive control.

8. A rotating electric machine (40) having a multi-phase armature winding (51U to 51W); a first inverter (20) having first upper arm switches (SUHa to SWHa) and first lower arm switches (SULa to SWLa) connected in series for the number of phases, and a series connection of the first upper arm switches and the first lower arm switches connected in parallel to a DC power source (10); a second inverter (30) having second upper arm switches (SUHb to SWHb) and second lower arm switches (SULb to SWLb) connected in series for the number of phases; a positive side bus (11) electrically connecting a high potential side terminal of the first upper arm switch and a high potential side terminal of the second upper arm switch in each phase; and a negative side bus (12) electrically connecting a low potential side terminal of the first lower arm switch and a low potential side terminal of the second lower arm switch in each phase. a changeover switch (QH, QL) provided on a target busbar that is at least one of the positive busbar and the negative busbar, the system being provided on a vehicle (200), and configured to transmit a rotational force of a rotor (41) of the rotating electric machine to wheels (220RL, 220RR, 210FL,210FR), in each phase, a low potential side terminal of the first upper arm switch and a high potential side terminal of the first lower arm switch are electrically connected to first ends (51Ua to 51Wa) of the armature windings, and in each phase, a low potential side terminal of the second upper arm switch and a high potential side terminal of the second lower arm switch are electrically connected to second ends (51Ub to 51Wb) of the armature windings, and the changeover switch electrically connects the first inverter and the second inverter via the target bus when turned on, and cuts off the electrical connection between the first inverter and the second inverter via the target bus when turned off, causing a processor (71) to execute a setting process for setting Y-drive control or H-drive control as the control mode of the first inverter and the second inverter, and a process for controlling the on or off of the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch based on the set control mode, The Y drive control is a control for fixing the second upper arm switch of each phase on and fixing the second lower arm switch of each phase off when the changeover switch is off, or fixing the second lower arm switch of each phase on and fixing the second upper arm switch of each phase off when the changeover switch is off, and turning the first upper arm switch and the first lower arm switch on and off, and the H drive control is a control for turning the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch on and off, and the program causes the processor to execute a determination process for determining whether or not the wheels are in a slipping state while the vehicle is traveling, and when it is determined by the determination process that the wheels are in a slipping state in the setting process, switches from one control mode currently set of the Y drive control or the H drive control to the other control mode.

9. A rotating electric machine (40) having a multi-phase armature winding (51U to 51W); a first inverter (20) having first upper arm switches (SUHa to SWHa) and first lower arm switches (SULa to SWLa) connected in series for the number of phases, the series-connected first upper arm switches and the first lower arm switches being connected in parallel to a DC power source (10); a second inverter (30) having second upper arm switches (SUHb to SWHb) and second lower arm switches (SULb to SWLb) connected in series for the number of phases; a positive bus (11) for each phase electrically connecting a high potential side terminal of the first upper arm switch and a high potential side terminal of the second upper arm switch; and a negative bus (12) for each phase electrically connecting a low potential side terminal of the first lower arm switch and a low potential side terminal of the second lower arm switch. a changeover switch (QH, QL) provided on a target busbar that is at least one of the positive busbar and the negative busbar, the system being provided on a vehicle (200), and a control method for a rotating electric machine, the system being provided on a vehicle (200), and a control method for a rotating electric machine, the control method being applied to a vehicle (200),210FR), in each phase, a low potential side terminal of the first upper arm switch and a high potential side terminal of the first lower arm switch are electrically connected to first ends (51Ua to 51Wa) of the armature windings, in each phase, a low potential side terminal of the second upper arm switch and a high potential side terminal of the second lower arm switch are electrically connected to second ends (51Ub to 51Wb) of the armature windings, the changeover switch electrically connects the first inverter and the second inverter via the target bus when turned on, and cuts off the electrical connection between the first inverter and the second inverter via the target bus when turned off, a setting step of setting Y drive control or H drive control as the control mode of the first inverter and the second inverter, and a step of controlling the on or off of the first upper arm switch, the first lower arm switch, the second upper arm switch and the second lower arm switch based on the set control mode, the Y drive control is a control method for controlling a rotating electric machine, the control being to fix the second upper arm switch of each phase on and fix the second lower arm switch of each phase off when the changeover switch is in an off state, or to fix the second lower arm switch of each phase on and fix the second upper arm switch of each phase off when the changeover switch is in an off state, and to turn on and off the first upper arm switch and the first lower arm switch, the H drive control being a control to turn on and off the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch, the method comprising a determination step of determining whether or not the wheels are in a slipping state while the vehicle is traveling, and when it is determined in the determination step that the wheels are in a slipping state in the setting step, switching from one of the control modes currently set among the Y drive control and the H drive control to the other control mode.

Images