Control device for rotary electric machine, program, and control method for rotary electric machine

Abstract

A control device (70) comprises a selection unit (85) and a switch control unit (86). The selection unit selects a control mode of first upper arm switches (SUHa to SWHa), first lower arm switches (SULa to SWLa), second upper arm switches (SUHb to SWHb), and second lower arm switches (SULb to SWLb). The switch control unit controls on or off of the first upper arm switches, the first lower arm switches, the second upper arm switches, and the second lower arm switches on the basis of the selected control mode. The selection unit selects Y drive control or H drive control as a control mode on the basis of the operation point (Trq *, Nr) of a rotary electric machine (40). Even when the Y drive control is selected on the basis of the operation point, the selection unit selects the H drive control when it is determined that a specific condition is satisfied.

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. 2023-214263, filed on December 19, 2023, 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. Drive control of the rotating electric machine is performed by switching control of the first and second inverters, thereby achieving high output and high efficiency of the system. An example of such a technology is disclosed in Patent Document 1.

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

[0005] In the above system, it is desirable to appropriately select the control modes of the first and second inverters.

[0006] A primary object of the present disclosure is to provide a control device for a rotating electric machine, a program, and a control method for a rotating electric machine that are capable of appropriately selecting the control modes of a first inverter and a second inverter.

[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 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 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 bus bar and the negative bus bar, wherein, 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, 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 a second end of the armature winding, 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, comprising: a selection unit that selects a control mode of the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch; 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 selected control mode, and the selection unit selects Y drive control or H drive control as the control mode based on an operating point of the rotating electric machine, and the Y drive control isThe control is such that when the changeover switch is turned off, the second upper arm switch of each phase is fixed on and the second lower arm switch of each phase is fixed off, or when the changeover switch is turned off, the second lower arm switch of each phase is fixed on and the second upper arm switch of each phase is fixed off, and the first upper arm switch and the first lower arm switch are PWM driven; the H drive control is such that the first upper arm switch, the first lower arm switch, the second upper arm switch and the second lower arm switch are PWM driven; and the selection unit selects the H drive control when it determines that a specific condition is met, even if the Y drive control is selected based on the operating point.

[0008] In the present disclosure, Y-drive control or H-drive control is selected as the control mode for each switch based on the operating point of the rotating electric machine.

[0009] Even if Y-drive control is selected, H-drive control is selected if it is determined that a specific condition is met, such as the condition that components of the rotating electrical machine or inverter are overheated.

[0010] According to the present disclosure, it is possible to appropriately select the control mode of each switch provided in the first and second inverters.

[0011] 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 an overall configuration diagram of a control system according to a first embodiment, Fig. 2 is a functional block diagram of control processing executed by a control device, Fig. 3 is a diagram showing areas of Y and H drive control, Fig. 4 is a diagram showing a control mode of H drive control, Fig. 5 is a diagram showing a control mode of Y drive control, Fig. 6 is a flowchart of control processing executed by a control device, Fig. 7 is a diagram showing an example of a pulse pattern, Fig. 8 is a time chart showing waveforms when interleaving control is performed, Fig. 9 is a time chart showing waveforms when interleaving control is not performed, Fig. 10 is a flowchart of control processing executed by a control device according to a second embodiment, Fig. 11 is a flowchart of control processing executed by a control device according to a third embodiment, and Fig. 12 is a flowchart of control processing executed by a control device according to a fourth embodiment. 16 is a diagram showing an overview of a battery ECU according to a sixth embodiment; FIG. 17 is a flowchart of control processing executed by a control device; FIG. 18 is a flowchart of control processing executed by a control device according to a seventh embodiment; FIG. 19 is a functional block diagram of control processing executed by a control device according to other embodiments; FIG. 20 is a diagram for explaining processing executed by a control device according to other embodiments; FIG. 21 is an overall configuration diagram of a control system according to other embodiments; and FIG. 22 is a diagram showing the control mode of Y drive control according to other embodiments.

[0012] 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.

[0013] A first embodiment of a control device according to the present disclosure will be described below with reference to the drawings. The control device of the present embodiment is applied to a control system mounted on an electrically powered vehicle such as an electric vehicle or a hybrid vehicle.

[0014] As shown in Fig. 1, the control system 100 includes a battery 10, which is a DC power supply, a first inverter 20, a second inverter 30, and a rotating electrical 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.

[0015] 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 .

[0016] 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.

[0017] 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.

[0018] 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.

[0019] 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.

[0020] 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.

[0021] The rotating electric machine 40 is an on-board main engine that serves as a power source for running the vehicle. The rotating electric machine 40 includes a rotor 41 and a stator 50. The rotor 41 is capable of transmitting power to the drive wheels of the vehicle. 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.

[0022] 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.

[0023] 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.

[0024] The control system 100 includes a changeover switch 13. The changeover switch 13 is provided on the positive bus 11 (corresponding to the "target bus"). The changeover switch 13 is, for example, a semiconductor switching element or a mechanical relay. When the changeover switch 13 is turned on, the changeover switch 13 electrically connects the collectors of the upper phase arm switches SUHa, SVHa, and SWHa of the first inverter 20 to the collectors of the upper phase arm switches SUHb, SVHb, and SWHb of the second inverter 30. When the changeover switch 13 is turned off, the changeover switch 13 electrically disconnects the collectors of the upper phase arm switches SUHa, SVHa, and SWHa of the first inverter 20 from the collectors of the upper phase arm switches SUHb, SVHb, and SWHb of the second inverter 30.

[0025] The changeover switch 13 may be, for example, an IGBT. In this case, a freewheel diode is connected in anti-parallel to the changeover switch 13. The collector of the IGBT is connected to the first inverter 20 side, and the emitter of the IGBT is connected to the second inverter 30 side.

[0026] Returning to the explanation of FIG. 1, the control system 100 includes a current sensor 60 , a rotation angle sensor 61 , a voltage sensor 62 , an inverter temperature sensor 63 , a motor temperature sensor 64 , a capacitor temperature sensor 65 , and a battery temperature sensor 66 .

[0027] 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 at one of the ends of each of the phase windings 51U, 51V, and 51W that is closer to the first inverter 20. Hereinafter, the sign of the phase current is defined as positive when the current flows from the first terminal 51Ua, 51Va, and 51Wa of each of the windings 51U, 51V, and 51W to the second terminal 51Ub, 51Vb, and 51Wb, and negative when the current flows from the second terminal 51Ub, 51Vb, and 51Wb to the first terminal 51Ua, 51Va, and 51Wa. Note that the current sensor 60 may also be provided at one of the ends of each of the phase windings 51U, 51V, and 51W that is closer to the second inverter 30.

[0028] 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 across the capacitor 15. The inverter temperature sensor 63 detects the temperatures of the first inverter 20 and the second inverter 30. For example, the inverter temperature sensor 63 detects the temperatures of the switches SUHa to SWLa and SUHb to SWLb that constitute each inverter 20, 30 as the temperatures of the first and second inverters 20, 30.

[0029] The motor temperature sensor 64 detects the temperature of the rotating electrical machine 40. The motor temperature sensor 64 detects the temperatures of the armature windings 51U to 51W, for example. The capacitor temperature sensor 65 detects the temperature of the capacitor 15. The battery temperature sensor 66 detects the temperature of the battery 10.

[0030] The detection values ​​of the sensors 60 to 66 are input to a control device 70 included in the control system 100. The control device 70 is an electronic control unit (ECU) that performs various controls of the control system 100, and includes a processor 71 and a storage unit 72 as hardware. In the control system 100, each on-board device can be controlled by an ECU corresponding to that device. However, for convenience, multiple ECUs are shown as a single control device 70 in FIG. 1.

[0031] 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 control device 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. 2 and 6, which will be described later.

[0032] For example, program information stored on a non-transient physical recording medium is installed in the storage unit 72. 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 unit 72.

[0033] In order to control the control variable of the rotary electric machine 40 to the command value, the control device 70 controls the changeover switch 13, the switches SUHa to SWLa of the first inverter 20, and the switches SUHb to SWLb of the second inverter 30 to turn on or off while the power switch 14 is on. In this embodiment, the control variable is torque.

[0034] FIG. 2 is a block diagram showing the control process of the rotating electrical machine 40 executed by the control device 70. As shown in FIG.

[0035] The command value calculation unit 80 calculates a d-axis current command value Id* and a q-axis current command value Iq* in a dq coordinate system based on the command torque Trq* received from a control device higher than the control device 70. When the command torque Trq* is positive, power running is performed. Power running is switching control of an inverter that converts DC power output from the battery 10 into AC power and supplies the converted AC power to the phase windings 51U, 51V, and 51W. When power running is performed, the rotating electric machine 40 functions as an electric motor. When the command torque Trq* is negative, regenerative driving is performed. Regenerative driving is switching control of an inverter that converts AC power generated by the rotating electric machine 40 into DC power and supplies the converted DC power to the battery 10. When regenerative driving is performed, the rotating electric machine 40 functions as a generator.

[0036] The two-phase conversion unit 81 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.

[0037] The current feedback unit 82 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 82 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 82 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.

[0038] The three-phase converter 83 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 voltages applied to the U-, V-, and W-phase windings 51U, 51V, and 51W. The U-, V-, and W-phase voltage command values ​​Vu*, Vv*, and Vw* are shifted in phase by 120° in electrical angle. In this embodiment, the sign of the applied voltage to each phase winding is positive when the potential at the first terminal 51Ua, 51Va, 51Wa of the windings 51U, 51V, 51W is higher than the potential at the second terminal 51Ub, 51Vb, 51Wb, and negative when the potential at the second terminal 51Ub, 51Vb, 51Wb of the windings 51U, 51V, 51W is higher than the potential at the first terminal 51Ua, 51Va, 51Wa.

[0039] The speed calculation unit 84 calculates the rotation speed Nr of the rotor 41 based on the electrical angle θr.

[0040] The selection unit 85 determines whether the drive state of the control system 100 should be Y drive control or H drive control. In the present embodiment, the selection unit 85 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 determined by the calculated rotation speed Nr and command torque Trq* and on the control map information.

[0041] 3 shows an example of the control map information. 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.

[0042] The selection unit 85 selects Y drive control when it determines that the rotation speed Nr is equal to or less than the determination threshold Jth. On the other hand, the selection unit 85 selects H drive control when it determines that the rotation speed Nr is higher than the determination threshold Jth or when it determines that the rotation speed Nr has exceeded a predetermined speed Nth. The determination threshold Jth increases as the command torque Trq* decreases in the region where the rotation speed Nr is equal to or less than the predetermined speed Nth.

[0043] Returning to the explanation of FIG. 2, the switch control unit 86 generates a carrier signal for generating drive signals for the switches SUHa-SWLa and SUHb-SWLb of the first and second inverters 20, 30. In this embodiment, the carrier signal is a triangular wave signal with equal increasing and decreasing speeds. The drive signals are comprised of switch on and off commands.

[0044] The switch control unit 86 generates drive signals for the switches SUHa to SWLa and SUHb to SWLb of the first and second inverters 20 and 30 based on the U-, V-, and W-phase voltage command values ​​Vu*, Vv*, and Vw*, the power supply voltage Vsr, which is the voltage detected by the voltage sensor 62, and the generated carrier signal.

[0045] Specifically, the switch control unit 86 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. 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 half the power supply voltage Vsr.

[0046] 4 , the switch control unit 86 performs H drive control by turning on the selector switch 13 to PWM-drive the switches SUHa to SWLa of the first inverter 20 and PWM-drive the switches SUHb to SWLb of the second inverter 30. The switch control unit 86 generates drive signals for the switches SUHa to SWLa and SUHb to SWLb of the first and second inverters 20 and 30 based on a magnitude comparison between the U-, V-, and W-phase normalized command values ​​Dutyu, Dutyv, and Dutyw and the carrier signal.

[0047] More specifically, the switch control unit 86 generates a first carrier signal Sg1 and a second carrier signal Sg2. The first carrier signal Sg1 is a signal for generating drive signals for the switches SUHa to SWLa of the first inverter 20. The second carrier signal Sg2 is a signal for generating drive signals for the switches SUHb to SWLb of the second inverter 30. The switch control unit 86 sets the phase difference between the first carrier signal Sg1 and the second carrier signal Sg2 to 0°.

[0048] The maximum value, minimum value, amplitude, and period of the first carrier signal Sg1 are the same as those of the second carrier signal Sg2, and therefore one switching period Tsw of each of the switches SUHa to SWLa and SUHb to SWLb is the same period.

[0049] The switch control unit 86 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 first carrier signal Sg1.

[0050] The switch control unit 86 calculates U-, V-, and W-phase inversion command values ​​1-Dutyu, 1-Dutyv, and 1-Dutyw, which are values ​​obtained by subtracting the U-, V-, and W-phase normalized command values ​​Dutyu, Dutyv, and Dutyw from 1 (100%). The switch control unit 86 generates drive signals for the switches SUHb to SWLb of the second inverter 30 based on a magnitude comparison between the calculated U-, V-, and W-phase inversion command values ​​1-Dutyu, 1-Dutyv, and 1-Dutyw and the second carrier signal Sg2.

[0051] On the other hand, when Y drive control is selected by the selector 85, the switch control unit 86 performs Y drive control by turning off the selector switch 13 and PWM-driving the switches SUHa to SWLa of the first inverter 20, as shown in FIG. 5 . The switch control unit 86 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. This results in a star connection of the phase windings 51U, 51V, and 51W via the second inverter 30. The switch control unit 86 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.

[0052] The maximum value, minimum value, amplitude, and period of the carrier signal used in the Y drive control are the same as those of the first carrier signal Sg1 used in the H drive control.

[0053] Based on the generated drive signal, the switch control unit 86 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 on / off of the switches SUHa-SWLa and SUHb-SWLb of the first and second inverters 20 and 30 is controlled in accordance with the drive signal.

[0054] The switching patterns of the switches of the inverters 20, 30, which are switching-controlled in accordance with the drive signal in the H drive control, are shifted in phase by 120° in electrical angle for each phase. Also, the switching patterns of the switches of the first inverter 20, which are switching-controlled in accordance with the drive signal in the Y drive control, are shifted in phase by 120° in electrical angle for each phase. The frequency of the voltage applied to each phase winding 51U, 51V, 51W in the H drive control is twice the frequency (e.g., 10 kHz) of the voltage applied to each phase winding 51U, 51V, 51W in the Y drive control.

[0055] In this embodiment, even if the selection unit 85 selects Y drive control based on the rotation speed Nr and the command torque Trq*, if it determines that a specific condition is met, it switches the selected control mode from Y drive control to H drive control.

[0056] 6 is a flowchart showing the control process of the rotary electric machine 40 executed by the control device 70. The process shown in FIG. 6 is repeatedly executed by the processor 71 of the control device 70, for example, at a predetermined control cycle.

[0057] In step S10, the command torque Trq* is acquired, and the speed calculation unit 84 calculates the rotation speed Nr.

[0058] In step S11, the selection unit 85 selects either the Y drive control or the H drive control based on the command torque Trq* and the rotation speed Nr.

[0059] If the H drive state is selected in step S11, the process proceeds to step S12, where the switch control section 86 executes the H drive control shown in FIG.

[0060] On the other hand, if the Y drive state is selected in step S11, the process proceeds to step S13, where it is determined whether the temperature detected by the motor temperature sensor 64 (hereinafter referred to as the motor temperature Tmt) is equal to or lower than the motor temperature threshold value Tmα. In this embodiment, the motor temperature Tmt is the temperature of each phase winding 51U, 51V, 51W. The motor temperature threshold value Tmα is, for example, the upper limit allowable temperature of each phase winding 51U, 51V, 51W that can maintain the reliability of each phase winding 51U, 51V, 51W. The motor temperature Tmt compared with the motor temperature threshold value Tmα may be, for example, the maximum or average value of the temperatures of each phase winding 51U, 51V, 51W.

[0061] If it is determined in step S13 that the motor temperature Tmt is equal to or lower than the motor temperature threshold value Tmα, the process proceeds to step S14, where the Y drive control shown in FIG. 5 is executed.

[0062] On the other hand, if it is determined in step S13 that the motor temperature Tmt exceeds the motor temperature threshold value Tmα, the process proceeds to step S15, where H drive control is selected.

[0063] The H drive control in step S15 is a switching control that causes less loss in the rotating electric machine 40 than the H drive control in step S12. For this control, the switch control unit 86 PWM-drives the switches SUHa to SWLb of the first and second inverters 20, 30 based on the electrical angle θr and a pulse pattern that is information that associates ON commands and OFF commands with the electrical angle θr. An example of the pulse pattern is shown in FIG. 7. The pulse pattern is a drive signal that is symmetrical about an electrical angle of 180°.

[0064] The pulse pattern of this embodiment is a pulse pattern that reduces iron loss in the rotating electric machine 40 compared to the H drive control in step S12, and is, for example, the pulse pattern described in Japanese Patent Application Laid-Open No. 2016-136838. Specifically, the pulse pattern for reducing iron loss is a pulse pattern determined under the condition that, among harmonic components contained in a pulse pattern subjected to Fourier analysis, harmonic components of specific orders that increase iron loss in the rotating electric machine 40 are reduced. More specifically, the pulse pattern is a pulse pattern determined under the condition that harmonic components of specific orders are set to zero. The specific orders of the harmonic components are, for example, the fifth and seventh orders.

[0065] After the process of step S15 is executed, if the determination in step S13 is affirmative, the process switches to Y drive control in step S14.

[0066] In this embodiment, even if Y-drive control is selected based on the operating point, if it is determined that the motor temperature Tmt exceeds the motor temperature threshold Tmα, H-drive control is executed in step S15. This reduces the current ripple flowing through the phase windings 51U, 51V, and 51W, thereby reducing iron loss in the rotating electric machine 40. As a result, the temperature rise of the phase windings 51U, 51V, and 51W can be suppressed.

[0067] The H drive control in step S15 can also be considered an interleaved control in which the polarity inversion period of the voltage applied to each phase winding 51U, 51V, 51W is shorter than that in the Y drive control in step S14. In other words, as described above, the frequency of the voltage applied to each phase winding 51U, 51V, 51W in the H drive control is twice the frequency of the voltage applied to each phase winding 51U, 51V, 51W in the Y drive control.

[0068] Figure 8 shows the transition of each waveform during interleaved control. Figure 8 and other figures show waveforms for only one phase in the control system 100. For this reason, the symbols U, V, and W that identify the phases have been removed from the symbols for each component.

[0069] 8, (a) shows the transition of the control state of the first upper arm switch SHa, and (b) shows the transition of the first voltage V1, which is the voltage of the winding on the side of the first inverter 20. The first upper arm switch SHa and the first lower arm switch SLa are not turned on simultaneously, but are turned on alternately.

[0070] 1C shows the transition of the control state of the second upper arm switch SHb, and 1D shows the transition of the second voltage V2, which is the voltage of the winding on the second inverter 30 side. The second upper arm switch SHb and the second lower arm switch SLb are not turned on simultaneously, but are turned on alternately.

[0071] 10(e) shows the change in the voltage difference ΔV obtained by subtracting the second voltage V2 from the first voltage V1, and FIG. 10(f) shows the change in the current Iph flowing from the battery 10 to the first inverter 20.

[0072] FIG. 9 shows the transition of each waveform in a comparative example in which interleave control is not performed.

[0073] In interleaved control, positive voltages and zero voltages are alternately applied to the windings. The phase difference between the center of the application period of the positive first voltage V1 and the center of the application period of the positive second voltage V2 is 180° electrical angle (i.e., Tsw / 2).

[0074] 8 and 9, with interleaved control, for example, the polarity inversion period of the voltage applied to each of the phase windings 51U, 51V, and 51W can be set to half the polarity inversion period of the voltage applied to each of the phase windings 51U, 51V, and 51W in the Y drive control of step S14. This reduces the current ripple shown in FIG. 8(f), and ultimately reduces iron loss in the rotating electric machine 40.

[0075] According to the present embodiment described above, it is possible to appropriately select a control mode so as to suppress the temperature rise of each of the phase windings 51U, 51V, 51W.

[0076] Second Embodiment A second embodiment will now be described with reference to the drawings, focusing on differences from the first embodiment. In this embodiment, the temperature of the first inverter 20 is used instead of the motor temperature Tmt.

[0077] 10 is a flowchart showing the control process of the rotary electric machine 40 executed by the control device 70. The process shown in FIG. 10 is repeatedly executed by the processor 71, for example, at a predetermined control cycle.

[0078] If the Y drive state is selected in step S11, the process proceeds to step S20, where it is determined whether the temperature of the first inverter 20 detected by the inverter temperature sensor 63 (hereinafter referred to as the first inverter temperature Tinv1) is equal to or lower than a first threshold value T1α. The first inverter temperature Tinv1 is, for example, the maximum value among the temperatures of the switches SUHa to SWLa of the first inverter 20. The first threshold value T1α is, for example, the upper limit temperature allowable for the first inverter 20 at which the reliability of the first inverter 20 can be maintained.

[0079] If it is determined in step S20 that the first inverter temperature Tinv1 is equal to or lower than the first threshold value T1α, the process proceeds to step S14.

[0080] On the other hand, if it is determined in step S20 that the first inverter temperature Tinv1 exceeds the first threshold value T1α, the process proceeds to step S21. In step S21, it is determined whether the temperature of the second inverter 30 detected by the inverter temperature sensor 63 (hereinafter referred to as the second inverter temperature Tinv2) exceeds the second threshold value T2α. The second inverter temperature Tinv2 is, for example, the maximum temperature among the temperatures of the switches SUHb to SWLb of the second inverter 30. The second threshold value T2α is, for example, the upper limit temperature allowable for the second inverter 30 at which the reliability of the second inverter 30 can be maintained. When the first and second inverters 20, 30 are used in the same manner, for example, the second threshold value T2α and the first threshold value T1α may be set to the same value.

[0081] If it is determined in step S21 that the second inverter temperature Tinv2 is equal to or lower than the second threshold value T2α, the process proceeds to step S22, where H drive control is selected. The frequency fh of the first and second carrier signals Sg1 and Sg2 used in the H drive control in step S22 is set to a frequency lower than the frequency fy of the carrier signal used in the Y drive control in step S14, specifically set to "fy / 2." As a result, the switching frequency of each switch SUHa-SWLb of the first and second inverters 20 and 30 in the H drive control in step S22 is lower than the switching frequency of each switch SUHa-SWLa of the first inverter 20 in the Y drive control in step S14, specifically set to half the frequency. This allows the number of switching operations per switching cycle in each of the first and second inverters 20 and 30 to be reduced compared to Y drive control. As a result, heat generation in the first inverter 20 can be suppressed.

[0082] Furthermore, the polarity inversion period of the voltage applied to each of the phase windings 51U, 51V, 51W in the H drive control of step S22 is the same as the polarity inversion period of the voltage applied to each of the phase windings 51U, 51V, 51W in the Y drive control of step S14. Therefore, even if the switching frequency is reduced in step S22, a decrease in the controllability of the controlled variable of the rotary electric machine 40 can be suppressed.

[0083] On the other hand, if it is determined in step S21 that the second inverter temperature Tinv2 exceeds the second threshold value T2α, the process proceeds to step S14, where Y drive control is selected, thereby preventing the second inverter 30 from overheating due to the continuation of the process in step S22.

[0084] According to the present embodiment described above, it is possible to appropriately select a control mode so as to suppress a rise in the temperature of the first inverter 20 .

[0085] Third Embodiment The first and second embodiments will be described below with reference to the drawings, focusing on differences from the first embodiment. In this embodiment, the temperature of the capacitor 15 is used instead of the motor temperature Tmt.

[0086] 11 is a flowchart showing the control process of the rotary electric machine 40 executed by the control device 70. The process shown in FIG. 11 is repeatedly executed by the processor 71, for example, at a predetermined control period.

[0087] If the Y drive state is selected in step S11, the process proceeds to step S30, where it is determined whether the temperature detected by the capacitor temperature sensor 65 (hereinafter referred to as capacitor temperature Tcnd) is equal to or lower than a capacitor temperature threshold value Tcα. The capacitor temperature threshold value Tcα is, for example, the upper limit temperature allowable for the capacitor 15 at which the reliability of the capacitor 15 can be maintained.

[0088] If it is determined in step S30 that the capacitor temperature Tcnd is equal to or lower than the capacitor temperature threshold value Tcα, the process proceeds to step S14.

[0089] On the other hand, if it is determined in step S30 that the capacitor temperature Tcnd exceeds the capacitor temperature threshold value Tcα, the process proceeds to step S31, where H drive control is selected.

[0090] The H drive control in step S31 is a switching control in which the current ripple flowing through the capacitor 15 is smaller than that in the H drive control in step S12. For this control, the switch control unit 86 PWM-drives the switches SUHb to SWLb of the second inverter 30 based on the electrical angle θr and the pulse pattern.

[0091] The pulse pattern of this embodiment is a pulse pattern that reduces the current ripple flowing through capacitor 15 compared to the H drive control in step S12, and is, for example, a pulse pattern described in Japanese Patent No. 6221958. More specifically, the pulse pattern for reducing the current ripple is a pulse pattern that is determined under the condition that it reduces harmonic components of specific orders among the harmonic components of the current flowing through capacitor 15. The specific orders are, for example, the 6th and 12th orders.

[0092] After the process of step S31 is executed, if an affirmative determination is made in step S30, the process switches to the Y drive control of step S14.

[0093] According to the present embodiment described above, it is possible to prevent the capacitor 15 from overheating in the region where Y drive control should be performed.

[0094] Fourth Embodiment A fourth embodiment will be described below with reference to the drawings, focusing on differences from the first embodiment. In this embodiment, the control system 100 includes a cooling device shown in FIG.

[0095] The cooling device cools the first and second inverters 20, 30, the rotating electric machine 40, and the battery 10 when switching control of the first and second inverters 20, 30 is performed to run the vehicle. Specifically, the cooling device includes a circulation path 200 through which coolant circulates, an electric water pump 201, a radiator 202, and an electric fan 203. The water pump 201 is powered and driven to circulate the coolant. In the example shown in FIG. 12 , the first inverter 20, the second inverter 30, the rotating electric machine 40, and the battery 10 are arranged in this order downstream of the water pump 201 in the circulation path 200. Note that the arrangement order of the devices in the circulation path 200 is not limited to the order shown in FIG. 12 .

[0096] A radiator 202 is provided in circulation path 200 between water pump 201 and battery 10. Radiator 202 cools the coolant that flows in via circulation path 200 and supplies the cooled coolant to water pump 201. The coolant that flows into radiator 202 is cooled by wind blown against radiator 202 as the vehicle moves and wind blown against radiator 202 by rotating fan 203. In this embodiment, circulation path 200, the coolant circulating through circulation path 200, and water pump 201 correspond to a "heat transfer unit" that transfers heat to battery 10, which is the target to be heated.

[0097] The control system 100 includes a water temperature sensor 67. The water temperature sensor 67 detects the temperature of the coolant circulating through the circulation path 200. The temperature detected by the water temperature sensor 67 (hereinafter referred to as the coolant temperature Thw) is input to the control device 70.

[0098] The water pump 201 and the fan 203 may be driven by a control device separate from the control device 70. However, in this embodiment, for convenience, it is assumed that the water pump 201 and the fan 203 are driven by the control device 70.

[0099] 13 is a flowchart showing the control process of the rotary electric machine 40 executed by the control device 70. The process shown in FIG. 13 is repeatedly executed by the processor 71, for example, at a predetermined control cycle.

[0100] If the Y drive state is selected in step S11, the process proceeds to step S40, where it is determined whether the coolant temperature Thw is equal to or lower than a water temperature threshold value Thα. The water temperature threshold value Thα is set, for example, from the viewpoint of ensuring that the temperatures of the first and second inverters 20, 30 do not exceed their respective upper limit temperatures, and that the temperature of the rotating electrical machine 40 does not exceed its own upper limit temperature.

[0101] If it is determined in step S40 that the coolant temperature Thw is equal to or lower than the water temperature threshold value Thα, the process proceeds to step S14.

[0102] On the other hand, if it is determined in step S40 that the coolant temperature Thw exceeds the water temperature threshold value Thα, the process proceeds to step S41. In step S41, the correction torque obtained by forcibly reducing the command torque Trq* received from the higher-level control device is used in the various processes shown in Fig. 2. As a result, the d-axis and q-axis current command values ​​Id* and Iq* are reduced, and switching control of the first and second inverters 20 and 30 is performed so that the torque of the rotating electrical machine 40 becomes a correction torque that is smaller than the command torque Trq*. As a result, temperature increases in the first and second inverters 20 and 30 and the rotating electrical machine 40 are suppressed.

[0103] In step S41, any of the following can be executed: (A) H drive control of step S15 in FIG. 6 in the first embodiment; (B) H drive control of step S22 in FIG. 10 in the second embodiment; or (C) H drive control of step S31 in FIG. 11 in the third embodiment. When control (A) is executed, iron loss of the rotating electric machine 40 can be reduced and a temperature rise of the rotating electric machine 40 can be suppressed with priority. When control (B) is executed, a temperature rise of the first inverter 20 can be suppressed with priority. When control (C) is executed, a temperature rise of the capacitor 15 can be suppressed with priority.

[0104] Note that any one of (A) to (C) may be executed, or the controls of (A) to (C) may be selected and executed.

[0105] According to the present embodiment described above, it is possible to appropriately select the control mode based on the coolant temperature Thw.

[0106] Fifth Embodiment A fifth embodiment will be described below with reference to the drawings, focusing on differences from the first to fourth embodiments. In this embodiment, the control device 70 changes the threshold value based on the power supply voltage Vsr detected by the voltage sensor 62.

[0107] 14, the higher the power supply voltage Vsr, the larger the threshold values ​​Tmα, T1α, T2α, Tcα, and Thα of the first to fourth embodiments are set by the selector 85 of the control device 70. As a result, the higher the power supply voltage Vsr, the larger the execution range of the Y drive control.

[0108] 15, when the rotary electric machine 40 is being regeneratively driven, the selection unit 85 sets the threshold values ​​Tmα, T1α, T2α, Tcα, and Thα to be smaller than when the rotary electric machine 40 is being powered. This expands the execution range of the H drive control during regenerative driving compared to powered driving.

[0109] The number of switches that are switched is greater in H drive control than in Y drive control, and the switching loss of the inverter increases. Therefore, during regenerative driving, the increase in the SOC of the battery 10 can be suppressed, and the effectiveness of regenerative braking on the drive wheels can be suppressed.

[0110] <Modification of Fifth Embodiment> The selector 85 may vary the thresholds Tmα, T1α, T2α, Tcα, and Thα in a stepwise manner based on the power supply voltage Vsr, instead of varying them continuously.

[0111] Sixth Embodiment A sixth embodiment will now be described with reference to the drawings, focusing on differences from the first to fifth embodiments. In this embodiment, the control device 70 changes the threshold value based on the state of the battery 10.

[0112] FIG. 16 is a diagram showing the battery ECU 250 included in the control system 100. The battery ECU 250 includes an input power calculation unit 251 and an output power calculation unit 252. The input power calculation unit 251 calculates the current input power Winr of the battery 10. The input power calculation unit 251 also calculates an upper limit input power WinH based on the state of the battery 10. The upper limit input power WinH is the maximum value of power that can be input to the battery 10. The state of the battery 10 includes the battery temperature Tbat detected by the battery temperature sensor 66 and the SOC of the battery 10. For example, the lower the battery temperature Tbat or the higher the SOC of the battery 10, the smaller the calculated upper limit input power WinH.

[0113] The output power calculation unit 252 calculates the current output power Woutr of the battery 10. The output power calculation unit 252 also calculates an upper limit output power WoutH based on the state of the battery 10. WoutH is the maximum value of power that can be output from the battery 10. For example, the higher the battery temperature Tbat or the higher the SOC of the battery 10, the larger the calculated upper limit output power WoutH.

[0114] The battery ECU 250 transmits the calculated input power Winr, output power Woutr, upper limit input power WinH, and upper limit output power WoutH to the control device 70. The SOC used in calculating the upper limit input power WinH and the upper limit output power WoutH may be, for example, the maximum value of the SOC of each unit battery constituting the battery 10 or the average value of the SOC of each unit battery.

[0115] 17 is a flowchart showing the threshold setting process executed by the selection unit 85 of the control device 70. The process shown in FIG. 17 is repeatedly executed by the processor 71, for example, at a predetermined control cycle.

[0116] In step S50, it is determined whether power driving or regenerative driving is being performed.

[0117] If it is determined in step S50 that power running is being performed, the process proceeds to step S51, where it is determined whether the received output power Woutr is equal to or greater than the output limit value Woth, which is the received upper limit output power WoutH or a value obtained by subtracting a margin ΔW from the upper limit output power WoutH.

[0118] If it is determined in step S51 that the output power Woutr is lower than the output limit value Woth, the process proceeds to step S52, where the threshold values ​​Tmα, T1α, T2α, Tcα, and Thα are set to default values.

[0119] On the other hand, if it is determined in step S51 that the output power Woutr is equal to or greater than the output limit value Woth, the process proceeds to step S53, where the threshold values ​​Tmα, T1α, T2α, Tcα, and Thα are increased from their default values. This allows the execution range of Y drive control to be expanded during power running. Y drive control has fewer switches to be switched than H drive control, so switching losses and the like are smaller and it is more efficient. Therefore, by expanding the execution range of Y drive control, the output power of the battery 10 required per unit torque is reduced, and it is possible to prevent the output power of the battery 10 from exceeding the upper limit output power WoutH.

[0120] If it is determined in step S50 that regenerative driving is being performed, the process proceeds to step S54, where it is determined whether the received input power Winr is equal to or greater than an input limit value With. The input limit value With is the received upper limit input power WinH or a value obtained by subtracting a margin ΔW from the upper limit input power WinH.

[0121] If it is determined in step S54 that the input power Winr is lower than the input limit value With, the process proceeds to step S52.

[0122] On the other hand, if it is determined in step S54 that the input power Winr is equal to or greater than the input limit value With, the process proceeds to step S55, where the threshold values ​​Tmα, T1α, T2α, Tcα, and Thα are set to be smaller than their default values. This allows the range of H drive control to be expanded during regenerative driving. H drive control involves a larger number of switches than Y drive control, resulting in greater switching losses and lower efficiency. Therefore, by expanding the range of H drive control, the power loss of each inverter 20, 30 relative to the power generated by the rotating electric machine 40 can be increased. As a result, the effectiveness of regenerative braking can be ensured while preventing the input power of the battery 10 from exceeding the upper limit input power WinH.

[0123] Seventh Embodiment The seventh embodiment will be described below with reference to the drawings, focusing on differences from the first to sixth embodiments. The control system 100 of this embodiment includes the cooling device shown in Fig. 12. In this embodiment, when there is a request to increase the temperature of the battery 10, the threshold value is reduced to 0 or a value close to 0.

[0124] 18 shows a flowchart of the threshold setting process executed by the selection unit 85 of the control device 70. The process shown in FIG. 18 is repeatedly executed by the processor 71, for example, at a predetermined control period.

[0125] In step S60, it is determined whether there is a request to increase the temperature of the battery 10. For example, if it is determined that the battery temperature Tbat is lower than the target temperature, it is determined that there is a request to increase the temperature.

[0126] If it is determined in step S60 that there is no temperature increase request, the process proceeds to step S61, where the threshold values ​​Tmα, T1α, T2α, Tcα, and Thα are set to default values.

[0127] On the other hand, if it is determined in step S60 that there is a temperature increase request, the process proceeds to step S62, where each threshold value Tmα, T1α, T2α, Tcα, and Thα is set to a value smaller than the default value, specifically, reduced to 0 or a value close to 0.

[0128] This allows the execution range of H drive control, which involves large switching losses, to be expanded, and the amount of heat generated to raise the temperature of the battery 10 to be increased.

[0129] When the control device 70 determines that there is a temperature increase request, it drives the water pump 201 so as to transfer the generated heat to the battery 10, which is the target for temperature increase, via the coolant in the circulation path 200.

[0130] According to the present embodiment described above, the temperature of the battery 10 can be raised quickly when the vehicle is placed in a low-temperature environment, while the vehicle is running, or while the vehicle is being externally charged while stopped.

[0131] Other Embodiments The above-described embodiments may be modified as follows.

[0132] In each of the above embodiments, control that can increase the torque of the rotary electric machine 40 may be applied.

[0133] First, the first example will be described with reference to FIG.

[0134] The control device 70 includes a zero-phase-sequence signal generating unit 87 and U-, V-, and W-phase superimposing units 88U, 88V, and 88W.

[0135] A zero-phase signal generating unit 87 generates a zero-phase signal V0* indicating a target value for the zero-phase current flowing through the U-, V-, and W-phase windings 51U, 51V, and 51W, and outputs the signal to U-, V-, and W-phase superimposing units 88U, 88V, and 88W. The zero-phase signal V0* is a sine wave signal having a frequency three times the frequency of the U-, V-, and W-phase voltage command values ​​Vu*, Vv*, and Vw*, for example.

[0136] The U, V, and W-phase superimposing units 88U, 88V, and 88W add a common zero-phase sequence signal V0* to the U, V, and W-phase voltage command values ​​Vu*, Vv*, and Vw*, and output the result to the switch control unit 86. The switch control unit 86 generates a drive signal using "Vu*+V0*, Vv*+V0*, and Vw*+V0*." This generates torque in the rotor 41 due to the magnetic interaction between the rotor 41 and the zero-phase sequence magnetic flux based on the zero-phase sequence current. As a result, the torque of the rotating electric machine 40 can be increased.

[0137] Next, a second example will be described with reference to FIG.

[0138] The control device 70 may perform H drive control so that a current "Ib+I0" obtained by superimposing an N×K-th harmonic current component I0 that generates zero-phase magnetic flux on a fundamental wave current component Ib that generates rotational magnetic flux in the rotor 41 flows through each of the phase windings 51U, 51V, and 51W. Here, N is the number of phases (3), and K is a positive integer, for example, 1. This makes it possible to increase the torque of the rotating electric machine 40 while reducing the peaks of the phase currents that flow through the phase windings 51U, 51V, and 51W.

[0139] The above-mentioned two methods are preferably applied simultaneously with the process of forcibly reducing the command torque Trq* in step S41 of FIG.

[0140] As shown in FIG. 21 , the control system 100 may include a second changeover switch 16 in addition to the first changeover switch 13. The second changeover switch 16 is provided on the negative bus 12. The second changeover switch 16 is, for example, a semiconductor switching element or a mechanical relay. When turned on, the second changeover switch 16 electrically connects the emitters of the lower phase arm switches SULa, SVLa, and SWLa of the first inverter 20 to the emitters of the lower phase arm switches SULb, SVLb, and SWLb of the second inverter 30. When turned off, the second changeover switch 16 electrically disconnects the emitters of the lower phase arm switches SULa, SVLa, and SWLa of the first inverter 20 from the emitters of the lower phase arm switches SULb, SVLb, and SWLb of the second inverter 30. The second changeover switch 16 may be, for example, an IGBT. In this case, a freewheel diode is connected in anti-parallel to the second changeover switch 16. The collector of the IGBT is connected to the second inverter 30 side, and the emitter of the IGBT is connected to the first inverter 20 side.

[0141] When H drive control is selected, the control device 70 turns on the first changeover switch 13 and the second changeover switch 16. On the other hand, when Y drive control is selected, the control device 70 turns off the first changeover switch 13 and the second changeover switch 16. In Y drive control, as shown in Fig. 22 , the control device 70 fixes the upper arm switches SUHb, SVHb, and SWHb of each phase of the second inverter 30 to off, and fixes the lower arm switches SULb, SVLb, and SWLb of the second inverter 30 to on. Note that in the configuration in which the control of Fig. 22 is performed, the first changeover switch 13 does not have to be provided in the control system 100.

[0142] In the seventh embodiment, the target to be heated may be, for example, the coolant in the circulation path 200. If the vehicle is equipped with an air conditioning system that uses the coolant as a heat source for heating the passenger compartment, the temperature of the heating heat source can be quickly increased. In this case, the selection unit 85 may determine that a temperature increase request exists when, for example, it is determined that the coolant temperature Thw is lower than the target temperature.

[0143] The heat transfer unit is not limited to a unit that uses cooling water as a cooling fluid, and may be, for example, an air-cooled unit that uses gas (air) as a cooling fluid, or may be a metal heat sink. When a heat sink is used as the heat transfer unit, for example, the first and second inverters 20, 30 and the battery 10 may be provided on the heat sink.

[0144] The carrier signal is not limited to a triangular wave signal, but may be, for example, a sawtooth wave signal.

[0145] In each of the above embodiments, the control device 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.

[0146] The DC power source is not limited to a battery, and may be, for example, a fuel cell.

[0147] The rotating electric machine is not limited to a permanent magnet field type synchronous machine, and may be, for example, an induction machine.

[0148] 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.

[0149] 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.

[0150] The inverter, rotating electric machine, and control device may be installed in a mobile body other than a vehicle, such as an aircraft or a ship. If the mobile body is an aircraft, the rotating electric machine serves as a power source for the aircraft's flight, and if the mobile body is a ship, the rotating electric machine serves as a power source for the ship's navigation. Furthermore, the inverter, rotating electric machine, and control device may be installed in a mobile body other than a vehicle.

[0151] 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.

[0152] The following describes characteristic configurations extracted from the above-described embodiments. [Configuration 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 body of the 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 (13, 16) provided on a target bus which is at least one of the positive bus and the negative bus, wherein, 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 a first end of the armature winding, 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 a second end of the armature winding, 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, and a selection unit (85) which selects a control mode of the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch; a switch control unit (86) that controls the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch to be on or off based on the selected control mode, wherein the selection unit selects Y drive control or H drive control as the control mode based on an operating point (Trq*, Nr) of the rotating electric machine,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 PWM driving the first upper arm switch and the first lower arm switch, The H drive control is a control for PWM driving the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch, The control device for a rotating electric machine according to configuration 1, [Configuration 3] The control device for a rotating electric machine according to Configuration 2, wherein, when the selection unit determines that the specific condition is met and selects the H-drive control, the selection unit shortens the polarity inversion period of the voltage applied to the armature winding compared to when the Y-drive control is selected. [Configuration 4] The control device for a rotating electric machine according to any one of Configurations 1 to 3, wherein the specific condition is a condition that the temperature (Tinv1) of the first inverter exceeds a threshold value (T1α). [Configuration 5] The control device for a rotating electric machine according to Configuration 4, wherein the threshold value is a first threshold value, and the selection unit selects the Y-drive control if, after determining that the specific condition is met and selecting the H-drive control, the selection unit determines that the temperature of the second inverter exceeds a second threshold value (T2α). [Configuration 6] The control device for a rotating electric machine according to any one of Configurations 1 to 5, wherein the system includes a capacitor (15) connected in parallel to a series connection of the first upper arm switch and the first lower arm switch, and the specific condition is a condition that the temperature (Tcnd) of the capacitor exceeds a threshold value (Tcα). [Configuration 7] The system includes a cooling device (200 to 203) containing a cooling fluid that cools the first inverter, the second inverter, and the rotating electric machine,The control device for a rotating electric machine according to any one of configurations 1 to 6, wherein the specific condition is a condition that a temperature (Thw) of the cooling fluid exceeds a threshold value (Thα). [Configuration 8] The control device for a rotating electric machine according to any one of configurations 2 to 7, wherein the selection unit increases the threshold value when a voltage (Vsr) of the DC power supply is high compared to when the voltage of the DC power supply is low. [Configuration 9] The control device for a rotating electric machine according to configuration 8, wherein the selection unit decreases the threshold value when the rotating electric machine is regeneratively driven compared to when the rotating electric machine is powered. [Configuration 10] The control device for a rotating electric machine according to any one of claims 2 to 9, wherein the selection unit increases the threshold value when it is determined that an output power (Woutr) of the DC power supply is equal to or greater than a limit value (Wth) when the rotating electric machine is powered. [Configuration 11] The control device for a rotating electric machine according to any one of claims 2 to 10, wherein the selection unit reduces the threshold value when it determines that the input power (Winr) of the DC power supply is equal to or greater than a limit value (With) in a state in which the rotating electric machine is regeneratively driven. [Configuration 12] The control device for a rotating electric machine according to any one of configurations 1 to 11, wherein the specific condition is a condition in which there is a request to increase the temperature of a temperature-increase target (10).

[0153] 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 connection of the 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 side bus (11) electrically connecting a high potential terminal of the first upper arm switch and a high potential terminal of the second upper arm switch in each phase; and a negative side bus (12) electrically connecting a low potential terminal of the first lower arm switch and a low potential terminal of the second lower arm switch in each phase. a changeover switch (13, 16) provided on a target busbar which is at least one of the positive busbar and the negative busbar; 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 a first end of the armature winding; 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 a second end of the armature winding; the changeover switch electrically connects the first inverter and the second inverter via the target busbar when turned on, and cuts off the electrical connection between the first inverter and the second inverter via the target busbar when turned off; a selection unit (85) which selects a control mode of the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch; a switch control unit (86) that controls the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch to be on or off based on the selected control mode, wherein the selection unit selects an operating point (Trq*,Nr), the Y drive control selects Y drive control or H drive control as the 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 in an off state, 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 in an off state, and PWM-driving the first upper arm switch and the first lower arm switch, the H drive control is a control for PWM-driving the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch, and the selection unit selects the H drive control when it determines that a specific condition is established, even if the Y drive control has been selected based on the operating point.

2. The control device for a rotating electric machine according to claim 1, wherein the specific condition is that the temperature (Tmt) of the rotating electric machine exceeds a threshold value (Tmα).

3. A control device for a rotating electric machine as described in claim 2, wherein when the selection unit determines that the specific condition is satisfied and selects the H drive control, the selection unit shortens the polarity inversion period of the voltage applied to the armature winding compared to when the Y drive control is selected.

4. A control device for a rotating electric machine according to any one of claims 1 to 3, wherein the specific condition is that the temperature (Tinv1) of the first inverter exceeds a threshold value (T1α).

5. The control device for a rotating electric machine as described in claim 4, wherein the threshold value is a first threshold value, and the selection unit selects the Y drive control if it determines that the temperature of the second inverter has exceeded a second threshold value (T2α) after determining that the specific condition is satisfied and selecting the H drive control.

6. A control device for a rotating electric machine according to any one of claims 1 to 3, wherein the system comprises a capacitor (15) connected in parallel to a series connection of the first upper arm switch and the first lower arm switch, and the specific condition is that the temperature (Tcnd) of the capacitor exceeds a threshold value (Tcα).

7. A control device for a rotating electric machine according to any one of claims 1 to 3, wherein the system comprises a cooling device (200 to 203) containing a cooling fluid that cools the first inverter, the second inverter and the rotating electric machine, and the specific condition is that the temperature (Thw) of the cooling fluid exceeds a threshold value (Thα).

8. The control device for a rotating electric machine according to claim 2 or 3, wherein the selection section increases the threshold value when the voltage (Vsr) of the DC power supply is high, more than when the voltage of the DC power supply is low.

9. The control device for a rotating electric machine according to claim 8, wherein the selection unit reduces the threshold value when the rotating electric machine is regeneratively driven, more than when the rotating electric machine is powered.

10. A control device for a rotating electric machine as described in claim 2 or 3, wherein the selection unit increases the threshold value when it determines that the output power (Woutr) of the DC power supply is equal to or greater than a limit value (Woth) when the rotating electric machine is powered.

11. A control device for a rotating electric machine as described in claim 2 or 3, wherein the selection unit reduces the threshold value when it determines that the input power (Winr) of the DC power source is equal to or greater than a limit value (With) when the rotating electric machine is regeneratively driven.

12. A control device for a rotating electric machine according to any one of claims 1 to 3, wherein the specific condition is a condition that there is a request to increase the temperature of an object (10) to be heated.

13. 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 connection of the 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 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 (13, 16) provided on a target busbar which is at least one of the positive busbar and the negative busbar, wherein 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 a first end of the armature winding, 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 a second end of the armature winding, and the changeover switch electrically connects the first inverter and the second inverter via the target busbar when turned on, and cuts off the electrical connection between the first inverter and the second inverter via the target busbar when turned off, and the program is applied to a system including: a changeover switch (13, 16) provided on a target busbar which is at least one of the positive busbar and the negative busbar, A process of controlling the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch to be on or off based on the selected control mode is executed, and in the selection process, an operating point (Trq*,Nr), the Y drive control or the H drive control is selected as the 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 in an off state, 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 in an off state, and for PWM driving the first upper arm switch and the first lower arm switch, and the H drive control is a control for PWM driving the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch, and the selection process selects the H drive control when it is determined that a specific condition is established, even if the Y drive control is selected based on the operating point.

14. 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 connection of the 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 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 (13, 16) provided on a target busbar which is at least one of the positive busbar and the negative busbar, wherein, 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 a first end of the armature winding, 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 a second end of the armature winding, the changeover switch electrically connects the first inverter and the second inverter via the target busbar when turned on, and cuts off the electrical connection between the first inverter and the second inverter via the target busbar when turned off, a selection step of selecting a control mode of the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch; and controlling the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch to be turned on or off based on the selected control mode, wherein in the selection step, an operating point (Trq*,Nr), Y-drive control or H-drive control is selected as the control mode, the Y-drive control being 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 in an off state, 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 in an off state, and for PWM-driving the first upper arm switch and the first lower arm switch, and the H-drive control being a control for PWM-driving the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch, and the H-drive control being selected when it is determined that a specific condition is established, even if the Y-drive control has been selected based on the operating point in the selection step.

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