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

Abstract

A control device (60) for a rotary electric machine is applied to a system (100) comprising: a rotary electric machine (40) having armature windings (51U, 51V, 51W) of multiple phases; a first inverter (20); a second inverter (30); a positive electrode-side bus bar (11); and a negative electrode-side bus bar (12). The control device (60) comprises: a switch control unit (71) for turning on and off each switch in a predetermined switching pattern; a learning unit (72) for learning a correction value (ΔD) for correcting a PWM control signal on the basis of a result detected by a current detection unit (16) when each switch is turned on and off by the switch control unit; and a correction unit (66) for correcting the pulse width of the PWM control signal to be long or short on the basis of the correction value.

Description

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

[0001] This application is based on Japanese Application No. 2023-219447 filed on December 26, 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 control program for a rotating electric machine, 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] Patent No. 7361222

[0005] In the above technology, the first inverter and the second inverter must be switched on and off in the same way. However, even if the same dead time is set for the first inverter and the second inverter, the pulse width may differ. In this case, for example, variations in the motor current may occur, which may increase common-node noise.

[0006] A primary object of the present disclosure is to provide a control device for a rotating electric machine, a control program for a rotating electric machine, and a control method for a rotating electric machine that are capable of causing an appropriate motor current to flow.

[0007] A first means for solving the above problem is a control device for a rotary electric machine that is applied to a system including: a rotary electric machine having armature windings of multiple phases; a first inverter having first upper arm switches and first lower arm switches connected in series for the same number of phases, and wherein the series-connected body of the first upper arm switches and the first lower arm switches is 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; and 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, wherein the first upper arm switch and the first lower arm switch are alternately turned on and off with a dead time therebetween, and the second upper arm switch and the second lower arm switch are alternately turned on and off with a dead time therebetween, a signal generating unit that generates a PWM control signal based on a torque command value of the rotary electric machine; a dead time generating unit that generates, based on the PWM control signal, an operation signal that controls the on / off state of each switch of each inverter so as to generate the dead time; a current detecting unit that detects a phase current flowing through the armature winding; a switch control unit that turns on and off each switch in a predetermined switching pattern; a learning unit that learns a correction value for correcting the PWM control signal based on the result detected by the current detecting unit when each switch is turned on and off by the switch control unit; and a correction unit that corrects the pulse width of the PWM control signal to be longer or shorter based on the correction value learned by the learning unit, wherein the switch control unit is capable of turning on and off each switch in a first switching pattern that alternates between on and off states of each switch of the first inverter while fixing the on / off state of each switch of the second inverter, and a second switching pattern that alternates between on and off states of each switch of the first inverter while fixing the on / off state of each switch of the first inverter,The learning unit learns and stores a correction value for the PWM control signal based on a comparison between the phase current detected by the current detection unit when each switch is turned on and off in the first switching pattern and the phase current detected by the current detection unit when each switch is turned on and off in the second switching pattern.

[0008] A second means for solving the above problem is a control program for a rotating electric machine executed by a control device of the rotating electric machine that is applied to a system including: a rotating electric machine having armature windings of multiple phases; a first inverter having first upper arm switches and first lower arm switches connected in series for the same number of phases, and wherein the series-connected body of the first upper arm switches and the first lower arm switches is 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; and 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, wherein the first upper arm switch and the first lower arm switch are alternately turned on and off with a dead time therebetween, and the second upper arm switch and the second lower arm switch are alternately turned on and off with a dead time therebetween, a signal generating step of generating a PWM control signal based on a torque command value of the rotary electric machine; a dead time generating step of generating, based on the PWM control signal, an operation signal for controlling the on / off state of each switch of each of the inverters so as to generate the dead time; a current detecting step of detecting a phase current flowing through the armature winding; a switch control step of turning on and off each of the switches in a predetermined switching pattern; a learning step of learning a correction value for correcting the PWM control signal based on the result detected in the current detecting step when each of the switches is turned on and off in the switch control step; and a correction step of lengthening or shortening the pulse width of the PWM control signal based on the correction value learned in the learning step, wherein the switch control step includes: a first switching pattern of alternately switching on and off the switches of the first inverter while fixing the on / off state of each switch of the second inverter;While the on / off state of each switch of the first inverter is fixed, the switches of the second inverter are turned on and off in a second switching pattern that alternately switches the on / off state of each switch of the first inverter, and in the learning step, a correction value of the PWM control signal is learned and stored based on a comparison between the phase current detected in the current detection step when each switch is turned on and off in the first switching pattern and the phase current detected in the current detection step when each switch is turned on and off in the second switching pattern.

[0009] A third means for solving the above problem is a control method for a rotating electric machine implemented by a control device of the rotating electric machine that is applied to a system including: a rotating electric machine having armature windings of multiple phases; a first inverter having first upper arm switches and first lower arm switches connected in series for the same number of phases, and wherein the series-connected body of the first upper arm switches and the first lower arm switches is 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; and 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, wherein the first upper arm switch and the first lower arm switch are alternately turned on and off with a dead time therebetween, and the second upper arm switch and the second lower arm switch are alternately turned on and off with a dead time therebetween, a signal generating step of generating a PWM control signal based on a torque command value of the rotary electric machine; a dead time generating step of generating, based on the PWM control signal, an operation signal for controlling the on / off state of each switch of each of the inverters so as to generate the dead time; a current detecting step of detecting a phase current flowing through the armature winding; a switch control step of turning on and off each of the switches in a predetermined switching pattern; a learning step of learning a correction value for correcting the PWM control signal based on the result detected by the current detecting step when each of the switches is turned on and off in the switch control step; and a correction step of lengthening or shortening the pulse width of the PWM control signal based on the correction value learned in the learning step, wherein the switch control step includes: a first switching pattern of alternately switching on and off the switches of the first inverter while fixing the on / off state of each switch of the second inverter;While the on / off state of each switch of the first inverter is fixed, the switches of the second inverter are turned on and off in a second switching pattern that alternately switches the on / off state of each switch of the first inverter, and in the learning step, a correction value of the PWM control signal is learned and stored based on a comparison between the phase current detected in the current detection step when each switch is turned on and off in the first switching pattern and the phase current detected in the current detection step when each switch is turned on and off in the second switching pattern.

[0010] According to the above means, even if the same dead time is provided, the pulse widths of the first inverter and the second inverter can be made closer to each other. Furthermore, even if the state of each inverter changes over time, the correction value is learned at a predetermined timing, so that the pulse widths of the first inverter and the second inverter can be made closer to each other.

[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. 10 is a timing chart of the gate signal for the 1B switching pattern; FIG. 11 is a diagram showing the current flow in the 2B switching pattern; FIG. 12 is a timing chart of the gate signal for the 2B switching pattern; FIG. 13 is a flowchart of the learning process; FIG. 14 is a diagram showing the pulse width before correction; FIG. 15 is a diagram showing the pulse width after correction; FIG. 16 is a diagram showing the pulse width before correction; and FIG. 17 is a diagram showing the pulse width after correction.

[0012] The present disclosure will now be described with reference to the drawings with respect to a control device, a control program, and a control method for a rotating electric machine. In the embodiments and the modifications, functionally and / or structurally corresponding and / or associated parts may be designated by the same reference numerals. For corresponding and / or associated parts, the description of the embodiments can be referenced.

[0013] The control device 60 for the rotating electric machine 40 of this embodiment is mounted on an electric vehicle such as an electric car or a hybrid car, and is applied to a control system 100 for the rotating electric machine 40 (hereinafter simply referred to as the control system 100).

[0014] As shown in FIG. 1, the control system 100 of this embodiment includes a battery 10, a first inverter 20, a second inverter 30, a rotating electric machine 40, and a control device 60 for the rotating electric machine (hereinafter, in the first embodiment, simply referred to as the control device 60).

[0015] The battery 10 is, for example, a battery pack including a series connection of unit cells, and is a DC power supply in this embodiment. 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.

[0016] 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 .

[0017] The first inverter 20 includes a series connection of a U-phase first upper arm switch SUHa and a U-phase first lower arm switch SULa, a V-phase first upper arm switch SVHa and a V-phase first lower arm switch SVLa, and a W-phase first upper arm switch SWHa and a W-phase first lower arm switch SWLa. Hereinafter, these will be collectively referred to as switches SUHa to SWLa.

[0018] Similarly, the second inverter 30 includes a series connection of a U-phase second upper arm switch SUHb and a U-phase second lower arm switch SULb, a series connection of a V-phase second upper arm switch SVHb and a V-phase second lower arm switch SVLb, and a series connection of a W-phase second upper arm switch SWHb and a W-phase second lower arm switch SWLb. Hereinafter, these will be collectively referred to as switches SUHb to SWLb.

[0019] In this embodiment, voltage-controlled semiconductor switching elements, more specifically, IGBTs, are used as the switches SUHa to SWLa and SUHb to SWLb. In this embodiment, the high-potential terminal of each switch is the collector, and the low-potential terminal is the emitter. Freewheeling diodes DUHa, DVHa, DWHa, DULa, DVLa, DWLa, DUHb, DVHb, DWHb, DULb, DVLb, and DWLb are connected in anti-parallel to the switches SUHa, SVHa, SWHa, SULa, SVLa, SWLa, SUHb, SVHb, SWHb, SULb, SVLb, and SWLb, respectively.

[0020] The collectors of the first upper arm switches SUHa, SVHa, SWHa of each phase and the collectors of the second upper arm switches SUHb, SVHb, SWHb of each phase are electrically connected by a positive bus 11 serving as a high-potential side connecting line such as a bus bar. The emitters of the first lower arm switches SULa, SVLa, SWLa of each phase and the emitters of the second lower arm switches SULb, SVLb, SWLb of each phase are electrically connected by a negative bus 12 serving as a low-potential side connecting line such as a bus bar.

[0021] The positive terminal of the battery 10 is electrically connected to the positive bus 11, and the negative terminal of the battery 10 is electrically connected to the negative bus 12. The battery 10 is electrically connected to the buses 11, 12 on the opposite side of the first inverter 20 from the second inverter 30.

[0022] The rotating electric machine 40 is, for example, a main motor mounted on a vehicle. A rotor 41 of the rotating electric machine 40 is capable of transmitting power to drive wheels (not shown) 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 (for example, neodymium magnets) as field poles.

[0023] The rotating electric machine 40 includes a stator 50. The stator 50 includes armature windings, namely, a U-phase winding 51U, a V-phase winding 51V, and a W-phase winding 51W. The phase windings 51U, 51V, and 51W are arranged with an electrical angle of 120°. The phase windings 51U, 51V, and 51W are open-connected, and both ends of each phase winding 51U, 51V, and 51W are electrically connected to the first inverter 20 or the second inverter 30.

[0024] Specifically, in each phase, first ends 51Ua, 51Va, 51Wa of the windings 51U, 51V, 51W are electrically connected to first upper switches SUHa, SVHa, SWHa and first lower switches SULa, SVLa, SWLa of the corresponding phase. Also, second ends 51Ub, 51Vb, 51Wb of the windings 51U, 51V, 51W are electrically connected to second upper switches SUHb, SVHb, SWHb and second lower switches SULb, SVLb, SWLb of the corresponding phase.

[0025] The control system 100 includes a changeover switch 13. The changeover switch 13 is provided on the positive electrode side bus 11 between the first inverter 20 and the second inverter 30. When the changeover switch 13 is turned on, it electrically connects the first inverter 20 and the second inverter 30, and when turned off, it electrically disconnects the first inverter 20 and the second inverter 30. The changeover switch 13 is controlled by the control device 60. The changeover switch 13 is provided to switch the driving state of the control system 100, as will be described later.

[0026] For example, the changeover switch 13 is a semiconductor switching element such as an IGBT or a relay. When an IGBT is used as the changeover switch 13, a freewheel diode is connected in parallel to the changeover switch 13. In this case, the anode of the freewheel diode is electrically connected to the second inverter 30 side, and the cathode is electrically connected to the first inverter 20 side.

[0027] The control system 100 includes a power switch 14 as a power switch unit, and a capacitor 15. The power switch 14 is, for example, a semiconductor switching element or a relay. The power switch 14 is provided on the positive bus 11 between the positive terminal of the battery 10 and the first inverter 20. When the power switch 14 is turned on, it electrically connects the battery 10 and the rotating electric machine 40, and when it is turned off, it electrically disconnects the battery 10 and the rotating electric machine 40. The power switch 14 is driven by the control device 60.

[0028] A first end of the capacitor 15 is electrically connected to the positive bus 11 between the power switch 14 and the first inverter 20. A second end of the capacitor 15 is electrically connected to the negative bus 12 between the negative terminal of the battery 10 and the first inverter 20.

[0029] The control system 100 includes a current sensor 16 and a rotation angle sensor 17 as current detection units. The current sensor 16 detects phase currents Iu, Iv, and Iw flowing through the respective phase windings 51U, 51V, and 51W. In this embodiment, the current sensor 16 is provided at one of both ends of each phase winding 51U, 51V, and 51W closer to the first inverter 20. The sign of the detected value of the current sensor 16 is positive when the current flows from the first terminal 51Ua, 51Va, and 51Wa of the winding 51U, 51V, and 51W to the second terminal 51Ub, 51Vb, and 51Wb of the winding 51U, 51V, and 51W for each phase, and negative when the current flows from the second terminal 51Ub, 51Vb, and 51Wb to the first terminal 51Ua, 51Va, and 51Wa. The current sensor 16 may be provided on the second inverter 30 side of either end of each of the phase windings 51U, 51V, 51W.

[0030] The rotation angle sensor 17 is, for example, a resolver, and detects the electrical angle θ of the rotor 41. The phase currents Iur, Ivr, and Iwr detected by the current sensor 16 and the electrical angle θr detected by the rotation angle sensor 17 are input to the control device 60.

[0031] The control system 100 includes a voltage sensor 18 that detects a system voltage Vsys between the positive bus 11 and the negative bus 12. The voltage sensor 18 is connected in parallel with the capacitor 15. That is, a first end of the voltage sensor 18 is electrically connected to the positive bus 11 between the power switch 14 and the first inverter 20. A second end of the voltage sensor 18 is electrically connected to the negative bus 12 between the negative terminal of the battery 10 and the first inverter 20. The detection result of the voltage sensor 18 is input to the control device 60. When the power switch 14 is turned on, the system voltage Vsys matches the power supply voltage of the battery 10, and when the power switch 14 is turned off, the system voltage Vsys matches the voltage across the capacitor 15.

[0032] The control device 60 is primarily composed of a microcomputer including a processing unit 60a such as a CPU and a storage unit 60b such as various types of memory. The functions provided by the microcomputer can be provided by software stored in a physical memory device and a computer executing the software, software alone, hardware alone, or a combination thereof. For example, when the microcomputer is provided by electronic circuits, which are hardware, the functions can be provided by digital circuits including numerous logic circuits or analog circuits. For example, the processing unit 60a of the microcomputer executes programs stored in a non-transitory tangible storage medium (non-transitory tangible storage medium) that serves as the storage unit 60b. The programs include, for example, control programs that realize the functions shown in FIG. 2 and the like. Execution of a program (e.g., a control program) results in the execution of a method (e.g., a control method) corresponding to the program. The storage unit 60b is, for example, a non-volatile memory. The programs stored in the storage unit 60b can be downloaded and updated via a communication network such as the Internet, for example, via OTA (Over the Air).

[0033] The control device 60 has a function of switching the drive state of the control system 100 between a Y drive state and an H drive state by controlling the selector switch 13. The control device 60 sets the control system 100 to the Y drive state by turning off the selector switch 13, turning on the second upper arm switches SUHb, SVHb, and SWHb of each phase, and turning off the lower arm switches SULb, SVLb, and SWLb of each phase. In the Y drive state, the phase windings 51U, 51V, and 51W are Y-connected via the second inverter 30. On the other hand, the control device 60 sets the control system 100 to the H drive state by turning on the selector switch 13.

[0034] In the Y drive state, the control device 60 controls the switching of the switches SUHa to SWLa in the first inverter 20. In addition, in the H drive state, the control device 60 controls the switching of both the switches SUHa to SWLa in the first inverter 20 and the switches SUHb to SWLb in the second inverter 30. By appropriately switching between the Y drive state and the H drive state and executing switching control, the control system 100 can be made to have a high output and high efficiency.

[0035] The control device 60 has various functions for controlling the switching of the switches SUHa to SWLa and SUHb to SWLb. These functions will be described below with reference to Fig. 2. The functions described below are realized at least in the H drive state.

[0036] 2 is a functional block diagram illustrating various functions for achieving switching control. The various functions of the control device 60 are realized, for example, by an arithmetic processing device 60a executing a program stored in a storage unit 60b. As shown in FIG. 2 , the control device 60 includes a current command generator 61, a dq converter 62, a current controller 63, a UVW converter 64, a duty ratio calculator 65, a correction unit 66, a modulator 67, and a dead time generator 68. In this embodiment, the current command generator 61, the dq converter 62, the current controller 63, the UVW converter 64, the duty ratio calculator 65, and the modulator 67 constitute a signal generator.

[0037] The current command generating unit 61 receives a torque command value Trq* from a higher-level control device than the control device 60. Based on the received torque command value Trq*, the current command generating unit 61 calculates a d-axis current command value Id* and a q-axis current command value Iq* in a dq coordinate system using a torque-dq map or the like. Hereinafter, the d-axis current command value Id* and the q-axis current command value Iq* may be collectively referred to as d- and q-axis current command values ​​Id* and Iq*.

[0038] The dq converter 62 receives the phase currents Iur, Ivr, and Iwr detected by the current sensor 16 and the electrical angle θr detected by the rotation angle sensor 17. The dq converter 62 calculates a d-axis current value Idr and a q-axis current value Iqr based on the detected phase currents Iur, Ivr, and Iwr and the electrical angle θr. The d-axis current value Idr and the q-axis current value Iqr may be collectively referred to as the d- and q-axis current values ​​Idr and Iqr.

[0039] The current control unit 63 receives the difference between the d-axis and q-axis current command values ​​Id* and Iq* and the d-axis and q-axis current values ​​Idr and Iqr. More specifically, the current control unit 63 receives the 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 input d-axis current deviation to zero. The current control unit 63 also receives the 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 input q-axis current deviation to zero. The feedback control is, for example, proportional-plus-integral control.

[0040] The d- and q-axis voltage command values ​​Vd* and Vq* and the detected electrical angle θr are input to the UVW converter 64. Based on the input d- and q-axis voltage command values ​​Vd* and Vq* and the electrical angle θr, the UVW converter 64 calculates a U-phase voltage command value Vu*, a V-phase voltage command value Vv*, and a W-phase voltage command value Vw*. Hereinafter, these may be collectively referred to as the respective phase voltage command values ​​Vu*, Vv*, and Vw*.

[0041] The phase voltage command values ​​Vu*, Vv*, and Vw* are command values ​​for the phase voltages Vu, Vv, and Vw. In this embodiment, the signs of the phase voltages Vu, Vv, and Vw are positive when the potentials of the first terminals 51Ua, 51Va, and 51Wa of the windings 51U, 51V, and 51W are higher than the potentials of the second terminals 51Ub, 51Vb, and 51Wb of the windings 51U, 51V, and 51W, respectively, and negative when the potentials of the second terminals 51Ub, 51Vb, and 51Wb of the windings 51U, 51V, and 51W are higher than the potentials of the first terminals 51Ua, 51Va, and 51Wa of the windings 51U, 51V, and 51W.

[0042] The phase voltage command values ​​Vu*, Vv*, Vw* and the system voltage Vsys are input to the duty ratio calculation unit 65. The duty ratio calculation unit 65 calculates the phase command time ratios DTu, DTv, DTw by normalizing the phase voltage command values ​​Vu*, Vv*, Vw* with the system voltage Vsys (power supply voltage).

[0043] The corrector 66 performs dead time compensation processing (correction processing using a duty ratio correction amount ΔD as a correction value) on the command time ratios DTu, DTv, DTw of each phase to calculate corrected command time ratios DTuc, DTvc, DTwc of each phase. The corrector 66 will be described in detail later.

[0044] The corrected phase command time ratios DTuc, DTvc, and DTwc are input to a modulator 67. The modulator 67 performs PWM processing based on a magnitude comparison between the corrected phase command time ratios DTuc, DTvc, and DTwc and the carrier signal CS to generate PWM control signals gu, gv, and gw, and outputs the PWM control signals to a dead time generator 68.

[0045] The carrier signal CS according to this embodiment is a triangular wave signal of a double-edge modulation type, specifically, a signal shaped like an isosceles triangle with equal increasing and decreasing rates. The increasing and decreasing rates are quantified, for example, by the amount of increase and decrease of the carrier signal CS per unit change in electrical angle. The carrier signal CS according to this embodiment is a signal whose minimum value is 0 and whose maximum value is 1.

[0046] The dead time generation unit 68 receives the PWM control signals gu, gv, and gw, and generates operation signals for the switches SUHa to SWLa of the first inverter 20 and operation signals gUp, gUn, gVp, gVn, gWp, and gWn for the switches SUHb to SWLb of the second inverter 30 based on the PWM control signals gu, gv, and gw.

[0047] The following description will be given taking the U-phase of the first inverter 20 as an example. The dead time generation unit 68 first generates a logically inverted signal of the U-phase PWM control signal gu, as shown in FIG. 3 . The dead time generation unit 68 delays the timing of switching the U-phase PWM control signal gu from logic L to logic H by the dead time Tdead to generate an operation signal gUp for operating the U-phase first upper arm switch SUHa. The dead time generation unit 68 delays the timing of switching the logically inverted signal from logic L to logic H by the dead time Tdead to generate an operation signal gUn for operating the U-phase first lower arm switch SULa. The operation signal according to this embodiment indicates ON with a logical H and OFF with a logical L.

[0048] The drive circuits (not shown) of the inverters 20 and 30 receive the operation signals generated as described above, and perform switching control of the first inverter 20 and the second inverter 30 based on the operation signals.

[0049] Next, the reason for providing the correction unit 66 in the control device 60 will be explained. By setting the dead time Tdead, the pulse width present in one electrical angle period increases or decreases depending on the operating state of each inverter 20, 30, such as the power factor. For example, the pulse width increases or decreases depending on the current direction. The pulse width also increases or decreases depending on the delay time of the drive circuit and each switch. Furthermore, the first inverter 20 and the second inverter 30 differ in terms of their arrangement positions, semiconductor switching element characteristics, deterioration state, noise conditions, and so on, which may cause the pulse width to increase or decrease between the first inverter 20 and the second inverter 30, resulting in differences.

[0050] Increasing or decreasing the pulse width causes the amplitude and phase of the fundamental wave component included in the output voltage of the inverters 20 and 30 to decrease or increase relative to the values ​​assumed at the time of design. This manifests itself as torque fluctuation, for example. To solve this problem, the control device 60 is provided with a correction unit 66.

[0051] However, the duty ratio correction amount ΔD is not constant and can change over time. For this reason, it is desirable to periodically learn and update the duty ratio correction amount ΔD. Therefore, this embodiment is provided with a learning function for learning and storing the duty ratio correction amount ΔD. This learning function will be described below.

[0052] 4 is a block diagram of various functions provided for learning and updating the duty ratio correction amount ΔD. Each function is realized, for example, by the arithmetic processing unit 60a executing a control program stored in the memory unit 60b.

[0053] 4, the control device 60 includes a switch control unit 71 and a learning unit 72. The switch control unit 71 has a function for turning on and off the switches SUHa to SWLa and SUHb to SWLb at predetermined times and in predetermined switching patterns. The predetermined times are times when the rotating electric machine 40 is not scheduled to be driven, such as when the vehicle is stopped or the ignition switch is off.

[0054] The switching patterns include a first switching pattern in which the on / off states of each of the switches SUHa to SWLa of the first inverter 20 are alternately switched while the on / off states of each of the switches SUHb to SWLb of the second inverter 30 are fixed, and a second switching pattern in which the on / off states of each of the switches SUHa to SWLa of the first inverter 20 are alternately switched while the on / off states of each of the switches SUHb to SWLb of the second inverter 30 are fixed.

[0055] To explain in more detail, as shown in Figures 5 and 6, the first switching pattern includes a 1A switching pattern in which the second upper arm switches SUHb, SVHb, and SWHb of all phases are fixed off and the second lower arm switches SULb, SVLb, and SWLb of all phases are fixed on, and the on / off states of each switch SUHa to SWLa of the first inverter 20 of all phases are alternately switched.

[0056] In FIG. 5 , the solid arrow indicates the current that flows when the first upper arm switch SUHa is turned on, and the dashed arrow indicates the current that flows (returning current) when the first upper arm switch SUHa is turned off (when the first lower arm switch SULa is turned on). The upper part of FIG. 6 shows the timing at which the first upper arm switch SUHa is turned on (i.e., the timing at which the gate signal is input) in the 1A switching pattern. The middle part of FIG. 6 shows the timing at which the first lower arm switch SULa is turned on (i.e., the timing at which the gate signal is input) in the 1A switching pattern. The lower part of FIG. 6 shows the phase current Iu (shown by the dashed line), which is the motor current that flows through the U-phase winding 51U, and the average current IAH (shown by the solid line) of the phase current Iu in the 1A switching pattern. The average current IAH is a positive current. While FIGS. 5 and 6 show the U-phase as a representative example, the same applies to the other phases.

[0057] As shown in Figures 7 and 8, the second switching pattern includes a second A switching pattern in which the first upper arm switches SUHa, SVHa, SWHa of all phases are fixed on and the first lower arm switches SULa, SVLa, SWLa of all phases are fixed off, and the on / off states of each switch SUHb to SWLb of the second inverter 30 of all phases are alternately switched.

[0058] In FIG. 7 , the solid arrow indicates the current that flows when the second lower arm switch SULb is turned on, and the dashed arrow indicates the current that flows (returning current) when the second lower arm switch SULb is turned off (when the second upper arm switch SUHb is turned on). The upper part of FIG. 8 shows the timing at which the second upper arm switch SUHb is turned on (i.e., the timing at which the gate signal is input) in the 2A switching pattern. The middle part of FIG. 8 shows the timing at which the second lower arm switch SULb is turned on (i.e., the timing at which the gate signal is input) in the 2A switching pattern. The lower part of FIG. 8 shows the phase current Iu (shown by the dashed line) and the average current IAL of the phase current Iu (shown by the solid line) in the 2A switching pattern. The average current IAL is a positive current. While FIGS. 7 and 8 show the U-phase as a representative example, the same applies to the other phases.

[0059] As shown in Figures 9 and 10, the first switching pattern includes a first B switching pattern in which the second upper arm switches SUHb, SVHb, and SWHb of all phases are fixed on and the second lower arm switches SULb, SVLb, and SWLb of all phases are fixed off, and the on / off states of each switch SUHa to SWLa of the first inverter 20 of all phases are alternately switched.

[0060] In FIG. 9 , the dashed arrow indicates the current (free-flowing current) that flows when the first lower-arm switch SULa is turned off (when the first upper-arm switch SUHa is turned on), and the solid arrow indicates the current that flows when the first lower-arm switch SULa is turned on. The upper part of FIG. 10 shows the timing at which the first upper-arm switch SUHa is turned on (i.e., the timing at which a gate signal is input) in the first-B switching pattern. The middle part of FIG. 10 shows the timing at which the first lower-arm switch SULa is turned on (i.e., the timing at which a gate signal is input) in the first-B switching pattern. The lower part of FIG. 10 shows the phase current Iu (shown by the dashed line), which is the motor current that flows through the U-phase winding 51U, and the average current IBL (shown by the solid line) of the phase current Iu in the first-B switching pattern. The average current IBL is a negative current. While FIGS. 9 and 10 show the U-phase as a representative example, the same applies to the other phases.

[0061] As shown in Figures 11 and 12, the second switching pattern includes a second B switching pattern in which the first upper arm switches SUHa, SVHa, SWHa of all phases are fixed off and the first lower arm switches SULa, SVLa, SWLa of all phases are fixed on, and the on / off states of each switch SUHb to SWLb of the second inverter 30 of all phases are alternately switched.

[0062] In FIG. 11 , the dashed arrow indicates the current (free-flowing current) that flows when the second upper arm switch SUHb is turned off (when the second lower arm switch SULb is turned on), and the solid arrow indicates the current that flows when the second upper arm switch SUHb is turned on. The upper part of FIG. 12 shows the timing at which the second upper arm switch SUHb is turned on (i.e., the timing at which a gate signal is input) in the second-B switching pattern. The middle part of FIG. 12 shows the timing at which the second lower arm switch SULb is turned on (i.e., the timing at which a gate signal is input) in the second-B switching pattern. The lower part of FIG. 12 shows the phase current Iu (shown by the dashed line) and the average current IBH (shown by the solid line) of the phase current Iu in the second-B switching pattern. The average current IBH is a negative current. While FIGS. 11 and 12 show the U-phase as a representative example, the same applies to the other phases.

[0063] The switch control unit 71 turns on and off each of the switches SUHa to SWLa and SUHb to SWLb using these switching patterns, and causes the current sensor 16 to detect the phase currents Iur, Ivr, and Iwr. The switch control unit 71 then averages the phase currents Iur, Ivr, and Iwr detected by the current sensor 16 to calculate average currents IAH, IAL, IBL, and IBH when the switches are operated using each switching pattern. The switch control unit 71 then outputs the calculated average currents IAH, IAL, IBL, and IBH to the learning unit 72.

[0064] It goes without saying that when the switch control unit 71 turns on and off the switches SUHa to SWLa and SUHb to SWLb, it utilizes the functions related to the switching control described above (the current command generation unit 61, dq conversion unit 62, current control unit 63, UVW conversion unit 64, duty ratio calculation unit 65, modulation unit 67, and dead time generation unit 68 shown in FIG. 2). It is assumed that the corrector 66 will learn the duty ratio correction amount ΔD, so it may or may not be used. If the corrector 66 is used, it is necessary to perform learning on the assumption that the correction has been made by the corrector 66.

[0065] In addition, when turning on and off each switch SUHa to SWLa, SUHb to SWLb, the switch control unit 71 controls the on and off so that current of the same magnitude flows through each phase winding 51U, 51V, 51W, in order to prevent torque from being generated in the rotating electric machine 40.

[0066] The learning unit 72 then learns the duty ratio correction amount ΔD as a correction value for the PWM control signal based on a comparison between the phase currents Iur, Ivr, and Iwr detected when each switch SUHa to SWLa, SUHb to SWLb is turned on and off in the first switching pattern and the phase currents Iur, Ivr, and Iwr detected when each switch is turned on and off in the second switching pattern.

[0067] More specifically, the learning unit 72 compares the average current IAH obtained when the switches are turned on and off using the first A switching pattern with the average current IAL obtained when the switches are turned on and off using the second A switching pattern. If the average current IAL is greater than the average current IAH (average current IAH < average current IAL), the learning unit 72 calculates a duty ratio correction amount ΔD for correcting the duty ratio so as to shorten the pulse width of the PWM control signal that turns on the second upper arm switches SUHb, SVHb, and SWHb. In this case (average current IAH < average current IAL), the learning unit 72 may calculate a duty ratio correction amount ΔD for correcting the duty ratio so as to lengthen the pulse width of the PWM control signal that turns on the first upper arm switches SUHa, SVHa, and SWHa. It should be noted that, since the value of the first inverter 20 disposed closer to the battery 10 is more likely to be correct (there is less fluctuation), it is generally desirable to calculate the duty ratio correction amount ΔD on the side of the second inverter 30, but either may be used.

[0068] On the other hand, when the average current IAL is smaller than the average current IAH (average current IAH > average current IAL), the learning unit 72 calculates a duty ratio correction amount ΔD for correcting the duty ratio so as to lengthen the pulse width of the PWM control signal that turns on the second upper arm switches SUHb, SVHb, and SWHb. In this case (average current IAH > average current IAL), the learning unit 72 may calculate a duty ratio correction amount ΔD for correcting the duty ratio so as to shorten the pulse width of the PWM control signal that turns on the first upper arm switches SUHa, SVHa, and SWHa. Note that if they match, there is no need to learn the duty ratio correction amount ΔD.

[0069] Furthermore, the learning unit 72 compares the average current IBL obtained when the switches are turned on and off using the first-B switching pattern with the average current IBH obtained when the switches are turned on and off using the second-B switching pattern. When the average current IBH is larger than the average current IBL (|average current IBL|<|average current IBH|), the learning unit 72 calculates a duty ratio correction amount ΔD for correcting the duty ratio so as to shorten the pulse width of the PWM control signal that turns on the second lower-arm switches SULb, SVLb, and SWLb. In this case (|average current IBL|<|average current IBH|), the learning unit 72 may calculate a duty ratio correction amount ΔD for correcting the duty ratio so as to lengthen the pulse width of the PWM control signal that turns on the first lower-arm switches SULa, SVLa, and SWLa.

[0070] Note that, since the average currents IBL and IBH are negative currents (see FIGS. 9 to 12), "the average current IBH is larger than the average current IBL" means "the absolute value of the average current IBH is larger than the absolute value of the average current IBL," and the magnitudes of the current values ​​themselves are compared. The same applies below when comparing the average currents IBL and IBH.

[0071] On the other hand, when the average current IBH is smaller than the average current IBL (|average current IBL|>|average current IBH|), the learning unit 72 calculates a duty ratio correction amount ΔD for correcting the duty ratio so as to lengthen the pulse width of the PWM control signal that turns on the second lower arm switches SULb, SVLb, and SWLb. In this case (|average current IBL|>|average current IBH|), the learning unit 72 may calculate a duty ratio correction amount ΔD for correcting the duty ratio so as to shorten the pulse width of the PWM control signal that turns on the first lower arm switches SULa, SVLa, and SWLa. Note that if the two values ​​match, there is no need to modify the duty ratio correction amount ΔD.

[0072] When calculating the duty ratio correction amount ΔD, the greater the difference between the average current IAH and the average current IAL or the difference between the average current IBL and the average current IBH, the greater the value calculated as the duty ratio correction amount ΔD. The learning unit 72 then stores the calculated duty ratio correction amount ΔD in the memory unit 60b in association with each of the switches SUHa to SWLa and SUHb to SWLb.

[0073] The flow of the learning process will now be described with reference to Fig. 13. The learning process is carried out at any timing during the predetermined period described above.

[0074] The switch control unit 71 of the control device 60 turns on and off each of the switches SUHa to SWLa and SUHb to SWLb in each switching pattern, obtains the detected phase currents Iur, Ivr, and Iwr, and calculates the average currents IAH, IAL, IBL, and IBH (step S101).

[0075] Next, the learning unit 72 of the control device 60 compares the average current IAH with the average current IAL, calculates the duty ratio correction amount ΔD for the second upper arm switches SUHb, SVHb, SWHb (or the first upper arm switches SUHa, SVHa, SWHa), and stores (learns) it (step S102).

[0076] The learning unit 72 of the control device 60 compares the average current IBH with the average current IBL, calculates the duty ratio correction amount ΔD for the second lower arm switches SULb, SVLb, SWLb (or the first lower arm switches SULa, SVLa, SWLa), and stores (learns) it (step S103).Then, the learning process ends.

[0077] It is not necessary to acquire and calculate all of the average currents IAH, IAL, IBL, and IBH, and it is also possible to acquire and calculate only the combination of the average currents IAH and IAL, or only the combination of the average currents IBL and IBH. If only the combination of the average currents IAH and IAL is calculated, only step S102 is performed, and if only the combination of the average currents IBH and IBL is calculated, only step S103 is performed.

[0078] Next, the dead time compensation process by the corrector 66 will be described. The corrector 66 reads the duty ratio correction amount ΔD stored in the memory unit 60b for the input command duty ratios DTu, DTv, DTw of each phase, and calculates the corrected command duty ratios DTuc, DTvc, DTwc of each phase based on the duty ratio correction amount ΔD. At this time, the corrector 66 reads the duty ratio correction amount ΔD for each of the switches SUHa to SWLa and SUHb to SWLb and performs the correction.

[0079] The effect of the correction will now be described. FIG. 14 shows the state before correction when a positive current is flowing, and FIG. 15 shows the state after correction when a positive current is flowing. The upper parts of FIGS. 14 and 15 show the phase command time ratio DTu (duty ratio) and carrier signal CS before correction, the middle parts show the on / off states of the first upper arm switch SUHa and the first lower arm switch SULa, and the lower parts show the voltage command value (ideal value) in dashed lines and the actual output voltage in solid lines. Note that while FIGS. 14 and 15 illustrate the first upper arm switch SUHa and the first lower arm switch SULa of the U phase, the same applies to the V phase and the W phase. Furthermore, although the first inverter 20 is illustrated, the same applies to the second inverter 30.

[0080] 14, it can be seen that the width of the output voltage (shown by the solid line) is narrower than the width of the voltage command value (shown by the dashed line). In this case, since the average current is smaller, the duty ratio correction amount ΔD is learned so that the pulse width becomes longer. Specifically, the duty ratio correction amount ΔD is learned so that the phase command duty ratio DTu becomes larger.

[0081] In this case, when the correction is performed, the phase command time ratio DTuc after the correction becomes larger than the phase command time ratio DTu before the correction, as shown in the upper part of Fig. 15. As a result, although the dead time Tdead remains unchanged, the pulse width during which the first upper arm switch SUHa is turned on becomes longer and the time during which the first lower arm switch SULa is turned off becomes longer, as shown in the middle part of Fig. 15. As a result, the width of the output voltage becomes longer so that the width of the voltage command value and the width of the output voltage become the same (or approach each other).

[0082] Next, the case where a negative current is flowed will be described. Fig. 16 shows the state before correction when a negative current is flowed, and Fig. 17 shows the state after correction when a negative current is flowed. The upper parts of Fig. 16 and Fig. 17 show the phase command time ratio DTu (duty ratio) and carrier signal CS before correction, the middle parts show the on / off states of the first upper arm switch SUHa and the first lower arm switch SULa, and the lower parts show the voltage command value (ideal value) with a dashed line and the actually output output voltage with a solid line.

[0083] In FIG. 16 , it can be seen that the width of the output voltage (indicated by the solid arrow) is longer than the width of the voltage command value (indicated by the dashed arrow). In this case, since the average current increases, the duty ratio correction amount ΔD is learned so as to shorten the pulse width. In this case, when correction is performed, as shown in the upper part of FIG. 17 , the phase command time ratio DTuc after correction becomes smaller than the phase command time ratio DTu before correction. As a result, as shown in the middle part of FIG. 17 , although the dead time Tdead remains unchanged, the pulse width during which the first upper arm switch SUHa is turned on becomes shorter, and the time during which the first lower arm switch SULa is turned off becomes shorter. As a result, the width of the output voltage becomes shorter so that the width of the voltage command value and the width of the output voltage become the same (or approach each other).

[0084] According to the above embodiment, the following effects are achieved.

[0085] As described above, the switch control unit 71 turns on and off the switches SUHa-SWLa and SUHb-SWLb in accordance with each switching pattern to calculate the average currents IAH, IAL, IBL, and IBH. The learning unit 72 then compares the average currents IAH and IAL to calculate and learn the duty ratio correction amount ΔD, and compares the average currents IBH and IBL to calculate and learn the duty ratio correction amount ΔD. The correction unit 66 performs correction using the learned duty ratio correction amount ΔD, so that the pulse widths of the first inverter 20 and the second inverter 30 can be made similar to each other even when dead times are provided in the same manner. Furthermore, even if the states of the inverters 20 and 30 change over time, the duty ratio correction amount ΔD is learned and updated at predetermined timing, so that the pulse widths of the first inverter 20 and the second inverter 30 can always be made similar to each other.

[0086] When switches SUHa to SWLa and SUHb to SWLb are turned on and off in each switching pattern, the same amount of phase current flows through windings 51U, 51V, and 51W of all phases, which prevents torque from being generated and allows switches SUHa to SWLa and SUHb to SWLb to be turned on and off in each switching pattern in an appropriate manner, such as when the vehicle is stopped.

[0087] The learning unit 72 performs comparison based on the average currents IAH, IAL, IBL, and IBH, which are the average values ​​of the detected phase currents. This reduces errors in the detected phase current values, enables proper comparison, and allows for appropriate calculation of the duty ratio correction amount ΔD.

[0088] (Modifications) Below, modifications in which the configuration of the above embodiment is partially changed will be described.

[0089] In the above embodiment, the switch control unit 71 turns on and off the switches SUHa to SWLa and SUHb to SWLb for all three phases. However, the switches may be turned on and off one phase at a time, or only two phases.

[0090] In the above embodiment, average currents are calculated and compared. As a modification, for example, the switch control unit 71 may acquire phase currents detected at the timing of switching from on to off, and the learning unit 72 may compare the phase currents detected at the timing of switching from on to off. In the case of PWM control, the timing at which each phase command time ratio DTuc, DTvc, or DTwc intersects with the carrier signal CS (time T1 or time T4 in FIG. 14 ) coincides with the timing of switching from on to off, making it easy to identify the timing. In other words, there is little error in the acquisition timing. Therefore, by comparing the phase currents detected at the timing of switching from on to off, there is little error and the comparison can be made appropriately.

[0091] For the same reason, the phase currents may be acquired at the timing when the carrier signal CS changes (time T3 in FIG. 14) and compared.

[0092] In the above embodiment, the switch control unit 71 may change the magnitude of the current when turning on and off the switches SUHa to SWLa and SUHb to SWLb in each switching pattern. More specifically, the pulse width may vary depending on the magnitude of the current. Therefore, the switch control unit 71 changes the phase current for each switching pattern and calculates multiple average currents IAH, IAL, IBL, and IBH. The learning unit 72 then calculates and stores (learns) the duty ratio correction amount ΔD in association with the magnitudes of the average currents IAH, IAL, IBL, and IBH. Since it is difficult to test all current amounts, the duty ratio correction amount ΔD may be learned for several current amounts and interpolated using linear interpolation or the like from the learned multiple duty ratio correction amounts ΔD.

[0093] The controller and methods described herein may be implemented by a special-purpose computer configured with a processor and memory programmed to perform one or more functions embodied in a computer program. Alternatively, the controller and methods described herein may be implemented by a special-purpose computer configured with a processor configured with one or more dedicated hardware logic circuits. Alternatively, the controller and methods described herein may be implemented by one or more special-purpose computers configured with a processor and memory programmed to perform one or more functions in combination with a processor configured with one or more hardware logic circuits. Furthermore, the computer program may be stored as instructions executed by a computer on a computer-readable non-transitory storage medium.

[0094] The following describes characteristic configurations extracted from the above-described embodiments.

[0095] [Configuration 1] A rotating electric machine (40) having a multi-phase armature winding (51U, 51V, 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. In a control device (60) for a rotating electric machine applied to a system (100) including the above, the first upper arm switch and the first lower arm switch are alternately turned on and off with a dead time (Tdead) therebetween, the second upper arm switch and the second lower arm switch are alternately turned on and off with a dead time therebetween, and a signal generating unit (61 to 65,a dead time generating unit (68) that generates, based on the PWM control signal, an operation signal for controlling the on / off state of each switch of each inverter so as to generate the dead time; a current detecting unit (17) that detects a phase current flowing through the armature winding; a switch control unit (71) that turns on and off each switch in a predetermined switching pattern; a learning unit (72) that learns a correction value (ΔD) for correcting the PWM control signal based on the result detected by the current detecting unit when each switch is turned on and off by the switch control unit; and a correction unit (66) that corrects the pulse width of the PWM control signal to be longer or shorter based on the correction value learned by the learning unit, wherein the switch control unit is capable of turning on and off each switch in a first switching pattern that alternates between on and off states of each switch of the first inverter while fixing the on / off state of each switch of the second inverter, and a second switching pattern that alternates between on and off states of each switch of the first inverter while fixing the on / off state of each switch of the first inverter, The control device for a rotating electric machine, wherein the learning unit learns and stores a correction value for the PWM control signal based on a comparison between the phase current detected by the current detection unit when each switch is turned on and off in the first switching pattern and the phase current detected by the current detection unit when each switch is turned on and off in the second switching pattern.

[0096] [Configuration 2] The first switching pattern includes a first A switching pattern that alternately switches on and off states of each switch of the first inverter with the second upper arm switch fixed to off and the second lower arm switch fixed to on; the second switching pattern includes a second A switching pattern that alternately switches on and off states of each switch of the second inverter with the first upper arm switch fixed to on and the first lower arm switch fixed to off; and the learning unit learns a correction value that corrects a duty ratio to lengthen the pulse width of a PWM control signal that turns on the first upper arm switch or a correction value that corrects a duty ratio to shorten the pulse width of a PWM control signal that turns on the second upper arm switch when the phase current (IAL) detected by the current detection unit in the second A switching pattern is larger than the phase current (IAH) detected by the current detection unit in the first A switching pattern; A control device for a rotating electric machine according to configuration 1, wherein when the phase current (IAL) detected by the current detection unit in the second A switching pattern is smaller than the phase current (IAH) detected by the current detection unit in the first A switching pattern, a correction value for correcting the duty ratio so as to shorten the pulse width of the PWM control signal that turns on the first upper arm switch, or a correction value for correcting the duty ratio so as to lengthen the pulse width of the PWM control signal that turns on the second upper arm switch, is learned.

[0097] [Configuration 3] The first switching pattern includes a firstB switching pattern that alternately switches on and off the switches of the first inverter with the second upper arm switch fixed on and the second lower arm switch fixed off, and the second switching pattern includes a secondB switching pattern that alternately switches on and off the switches of the second inverter with the first upper arm switch fixed off and the first lower arm switch fixed on, and the learning unit learns a correction value that corrects a duty ratio to lengthen the pulse width of a PWM control signal that turns on the first lower arm switch or a correction value that corrects a duty ratio to shorten the pulse width of a PWM control signal that turns on the second lower arm switch when the phase current (IBH) detected by the current detection unit in the secondB switching pattern is larger than the phase current (IBL) detected by the current detection unit in the firstB switching pattern, 3. The control device for a rotating electric machine according to configuration 1 or 2, wherein when the phase current (IBH) detected by the current detection unit in the second B switching pattern is smaller than the phase current (IBL) detected by the current detection unit in the first B switching pattern, a correction value for correcting the duty ratio so as to shorten the pulse width of the PWM control signal that turns on the first lower arm switch, or a correction value for correcting the duty ratio so as to lengthen the pulse width of the PWM control signal that turns on the second lower arm switch, is learned.

[0098] [Configuration 4] The control device for a rotating electric machine according to any one of configurations 1 to 3, wherein the rotating electric machine has a three-phase armature winding, and the switch control unit causes phase currents of the same magnitude to flow through the armature windings of all phases when turning on and off each of the switches in the first switching pattern or the second switching pattern.

[0099] [Configuration 5] The control device for a rotating electric machine according to any one of configurations 1 to 3, wherein the learning unit stores a correction value corresponding to the current value of the phase current detected by the current detection unit in the first switching pattern or the current value of the phase current detected by the current detection unit in the second switching pattern.

[0100] [Configuration 6] The control device for a rotating electric machine according to any one of Configurations 1 to 3, wherein the learning unit compares the phase currents detected at the timings (T1, T4) when the switches are switched from on to off.

[0101] [Configuration 7] The control device for a rotating electric machine according to any one of configurations 1 to 3, wherein the learning unit performs the comparison based on average values ​​of the detected phase currents.

[0102] [Configuration 8] The control device for a rotating electric machine according to any one of configurations 1 to 3, wherein the learning unit learns and stores a correction value so that the phase current detected by the current detection unit in the second switching pattern approaches the phase current detected by the current detection unit in the first switching pattern.

[0103] [Configuration 9] A rotating electric machine (40) having a multi-phase armature winding (51U, 51V, 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 control program for a rotating electric machine executed by a control device (60) for a rotating electric machine applied to a system (100) including the above-mentioned, wherein the first upper arm switch and the first lower arm switch are alternately turned on and off with a dead time (Tdead) therebetween, and the second upper arm switch and the second lower arm switch are alternately turned on and off with a dead time therebetween, and a signal generating step (61 to 65) for generating a PWM control signal based on a torque command value of the rotating electric machine.a dead time generating step (68) of generating an operation signal for controlling the on / off state of each switch of each inverter based on the PWM control signal so as to generate the dead time; a current detecting step (17) of detecting a phase current flowing through the armature winding; a switch control step (71) of turning on and off each switch in a predetermined switching pattern; a learning step (72) of learning a correction value (ΔD) for correcting the PWM control signal based on the result detected by the current detecting step when each switch is turned on and off in the switch control step; and a correction step (66) of correcting the pulse width of the PWM control signal to be longer or shorter based on the correction value learned in the learning step, wherein the switch control step turns on and off each switch in a first switching pattern of alternately switching on and off each switch of the first inverter while fixing the on / off state of each switch of the second inverter, and a second switching pattern of alternately switching on and off each switch of the second inverter while fixing the on / off state of each switch of the first inverter, a control program for a rotating electric machine, wherein the learning step learns and stores a correction value of the PWM control signal based on a comparison between the phase current detected in the current detection step when each switch is turned on and off in the first switching pattern and the phase current detected in the current detection step when each switch is turned on and off in the second switching pattern.

[0104] [Configuration 10] A rotating electric machine (40) having a multi-phase armature winding (51U, 51V, 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 control method for a rotating electric machine implemented by a control device (60) for a rotating electric machine applied to a system (100) including the above-mentioned, wherein the first upper arm switch and the first lower arm switch are alternately turned on and off with a dead time (Tdead) therebetween, and the second upper arm switch and the second lower arm switch are alternately turned on and off with a dead time therebetween, and a signal generating step (61 to 65) for generating a PWM control signal based on a torque command value of the rotating electric machine.a dead time generating step (68) of generating an operation signal for controlling the on / off state of each switch of each inverter based on the PWM control signal so as to generate the dead time; a current detecting step (17) of detecting a phase current flowing through the armature winding; a switch control step (71) of turning on and off each switch in a predetermined switching pattern; a learning step (72) of learning a correction value (ΔD) for correcting the PWM control signal based on the result detected by the current detecting step when each switch is turned on and off in the switch control step; and a correction step (66) of correcting the pulse width of the PWM control signal to be longer or shorter based on the correction value learned in the learning step, wherein the switch control step turns on and off each switch in a first switching pattern of alternately switching on and off each switch of the first inverter while fixing the on / off state of each switch of the second inverter, and a second switching pattern of alternately switching on and off each switch of the second inverter while fixing the on / off state of each switch of the first inverter, In the learning step, a correction value of the PWM control signal is learned and stored based on a comparison between the phase current detected in the current detection step when each switch is turned on and off in the first switching pattern and the phase current detected in the current detection step when each switch is turned on and off in the second switching pattern.

[0105] 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, 51V, 51W), a first inverter (20) having a number of series-connected first upper arm switches (SUHa to SWHa) and first lower arm switches (SULa to SWLa) corresponding to the number of phases, with the series connection of the first upper arm switches and the first lower arm switches being connected in parallel to a DC power supply (10), a second inverter (30) having a number of series-connected second upper arm switches (SUHb to SWHb) and second lower arm switches (SULb to SWLb) corresponding to the number of phases, a positive bus bar (11) electrically connecting the high-potential side terminals of the first upper arm switches and the high-potential side terminals of the second upper arm switches in each phase, and a negative bus bar (12) electrically connecting the low-potential side terminals of the first lower arm switches and the low-potential side terminals of the second lower arm switches in each phase. In a control device (60) for the rotating electric machine applied to a system (100), the first upper arm switch and the first lower arm switch are alternately turned on and off with a dead time (Tdead) in between, the second upper arm switch and the second lower arm switch are alternately turned on and off with a dead time in between, and a signal generation unit (61 to 65,67), and a dead-time generation unit (68) that generates an operation signal for controlling the on / off state of each switch of each inverter so that the dead time occurs based on the PWM control signal, a current detection unit (16) that detects the phase current flowing through the armature winding, a switch control unit (71) that turns on and off each switch in a predetermined switching pattern, and a learning unit (72) that learns a correction value (ΔD) for correcting the PWM control signal based on the result detected by the current detection unit when each switch is turned on and off by the switch control unit, and a correction unit (66) that corrects the pulse width of the PWM control signal to be longer or shorter based on the correction value learned by the learning unit. The switch control unit can turn on and off each switch in a first switching pattern in which the on / off state of each switch of the second inverter is fixed and the on / off state of each switch of the first inverter is alternately switched, and a second switching pattern in which the on / off state of each switch of the first inverter is fixed and the on / off state of each switch of the second inverter is alternately switched. The learning unit learns and stores the correction value of the PWM control signal based on a comparison between the phase current detected by the current detection unit when each switch is turned on and off in the first switching pattern and the phase current detected by the current detection unit when each switch is turned on and off in the second switching pattern. A control device for a rotating electrical machine., 2. The first switching pattern includes a first A switching pattern that alternately switches the on / off states of the switches of the first inverter with the second upper arm switch fixed off and the second lower arm switch fixed on. The second switching pattern includes a second A switching pattern that alternately switches the on / off states of the switches of the second inverter with the first upper arm switch fixed on and the first lower arm switch fixed off. When the phase current (IAL) detected by the current detection unit in the second A switching pattern is larger than the phase current (IAH) detected by the current detection unit in the first A switching pattern, the learning unit learns a correction value for correcting the duty ratio so as to increase the pulse width of the PWM control signal for turning on the first upper arm switch, or a correction value for correcting the duty ratio so as to decrease the pulse width of the PWM control signal for turning on the second upper arm switch. When the phase current (IAL) detected by the current detection unit in the second A switching pattern is smaller than the phase current (IAH) detected by the current detection unit in the first A switching pattern, the learning unit learns a correction value for correcting the duty ratio so as to decrease the pulse width of the PWM control signal for turning on the first upper arm switch, or a correction value for correcting the duty ratio so as to increase the pulse width of the PWM control signal for turning on the second upper arm switch. The control device for a rotating electrical machine according to claim 1.

3. The first switching pattern includes a first B switching pattern in which each switch of the first inverter is alternately switched between on and off states with the second upper arm switch fixed on and the second lower arm switch fixed off. The second switching pattern includes a second B switching pattern in which each switch of the second inverter is alternately switched between on and off states with the first upper arm switch fixed off and the first lower arm switch fixed on. When the phase current (IBH) detected by the current detection unit in the second B switching pattern is greater than the phase current (IBL) detected by the current detection unit in the first B switching pattern, the learning unit learns a correction value for correcting the duty ratio so as to increase the pulse width of the PWM control signal for turning on the first lower arm switch, or a correction value for correcting the duty ratio so as to decrease the pulse width of the PWM control signal for turning on the second lower arm switch. When the phase current (IBH) detected by the current detection unit in the second B switching pattern is less than the phase current (IBL) detected by the current detection unit in the first B switching pattern, the learning unit learns a correction value for correcting the duty ratio so as to decrease the pulse width of the PWM control signal for turning on the first lower arm switch, or a correction value for correcting the duty ratio so as to increase the pulse width of the PWM control signal for turning on the second lower arm switch. The control device for a rotating electrical machine according to claim 1.

4. The rotating electrical machine has three-phase armature windings. When turning on and off each switch according to the first switching pattern or the second switching pattern, the switch control unit causes the same magnitude of phase current to flow through the armature windings of all phases. The control device for a rotating electrical machine according to any one of claims 1 to 3.

5. The learning unit stores a correction value corresponding to the current value of the phase current detected by the current detection unit in the first switching pattern or the current value of the phase current detected by the current detection unit in the second switching pattern. The control device for a rotating electrical machine according to any one of claims 1 to 3.

6. The control device for a rotating electrical machine according to any one of claims 1 to 3, wherein the learning unit compares the phase currents detected at the timings (T1, T4) when each of the switches is switched from on to off.

7. The control device for a rotating electrical machine according to any one of claims 1 to 3, wherein the learning unit performs the comparison based on the average value of the detected phase currents.

8. The control device for a rotating electrical machine according to any one of claims 1 to 3, wherein the learning unit learns and stores a correction value so that the phase current detected by the current detection unit in the second switching pattern approaches the phase current detected by the current detection unit in the first switching pattern.

9. A rotating electrical machine (40) having a multi-phase armature winding (51U, 51V, 51W), a first inverter (20) having a number of upper arm switches (SUHa to SWHa) and lower arm switches (SULa to SWLa) connected in series, the series connection of the first upper arm switch and the first lower arm switch being connected in parallel to a DC power supply (10), a second inverter (30) having a number of upper arm switches (SUHb to SWHb) and lower arm switches (SULb to SWLb) connected in series, a positive bus bar (11) electrically connecting the high potential side terminals of the first upper arm switch and the second upper arm switch in each phase, and a negative bus bar (12) electrically connecting the low potential side terminals of the first lower arm switch and the second lower arm switch in each phase. In a control program for a rotating electrical machine implemented by a control device (60) of a rotating electrical machine applied to a system (100), the first upper arm switch and the first lower arm switch are alternately turned on and off with a dead time (Tdead) in between, the second upper arm switch and the second lower arm switch are alternately turned on and off with a dead time in between, a signal generation step of generating a PWM control signal based on a torque command value of the rotating electrical machine, a dead time generation step of generating an operation signal for controlling the on / off state of each switch of each inverter so that the dead time occurs based on the PWM control signal, a current detection step of detecting a phase current flowing through the armature winding, a switch control step of turning on and off each switch in a predetermined switching pattern, a learning step of learning a correction value (ΔD) for correcting the PWM control signal based on the result detected by the current detection step when each switch is turned on and off in the switch control step, and a correction step of correcting the pulse width of the PWM control signal to be longer or shorter based on the correction value learned by the learning step are performed. In the switch control step,A control program for a rotating electrical machine that, with the on / off states of the switches of the second inverter fixed, alternately switches the on / off states of the switches of the first inverter in a first switching pattern, turns on and off each switch in a second switching pattern that alternately switches the on / off states of the switches of the second inverter with the on / off states of the switches of the first inverter fixed, and in the learning step, learns and stores a correction value of the PWM control signal based on a comparison between the phase current detected in the current detection step when each switch is turned on and off in the first switching pattern and the phase current detected in the current detection step when each switch is turned on and off in the second switching pattern.

10. A rotating electrical machine (40) having a multi-phase armature winding (51U, 51V, 51W), a first inverter (20) having a number of series-connected first upper-arm switches (SUHa to SWHa) and first lower-arm switches (SULa to SWLa) corresponding to the number of phases, with the series connection of the first upper-arm switches and the first lower-arm switches being connected in parallel to a DC power supply (10), a second inverter (30) having a number of series-connected second upper-arm switches (SUHb to SWHb) and second lower-arm switches (SULb to SWLb) corresponding to the number of phases, a positive bus bar (11) electrically connecting the high-potential terminals of the first upper-arm switches and the high-potential terminals of the second upper-arm switches in each phase, and a negative bus bar (12) electrically connecting the low-potential terminals of the first lower-arm switches and the low-potential terminals of the second lower-arm switches in each phase. In a control method for a rotating electrical machine implemented by a control device (60) of the rotating electrical machine applied to a system (100), the first upper-arm switch and the first lower-arm switch are alternately turned on and off with a dead time (Tdead) in between, the second upper-arm switch and the second lower-arm switch are alternately turned on and off with a dead time in between, a signal generation step of generating a PWM control signal based on the torque command value of the rotating electrical machine, a dead time generation step of generating an operation signal for controlling the on / off state of each switch of each inverter so that the dead time occurs based on the PWM control signal, a current detection step of detecting the phase current flowing through the armature winding, a switch control step of turning on and off each switch in a predetermined switching pattern, a learning step of learning a correction value (ΔD) for correcting the PWM control signal based on the result detected by the current detection step when each switch is turned on and off in the switch control step, and a correction step of correcting the pulse width of the PWM control signal to be longer or shorter based on the correction value learned in the learning step. In the switch control step, a first switching pattern in which the on / off state of each switch of the first inverter is alternately switched with the on / off state of each switch of the second inverter fixed,With the on / off states of the switches of the first inverter fixed, the switches are turned on and off in a second switching pattern in which the on / off states of the switches of the second inverter are alternately switched. In the learning step, based on a comparison between the phase current detected in the current detection step when the switches are turned on and off in the first switching pattern and the phase current detected in the current detection step when the switches are turned on and off in the second switching pattern, a correction value of the PWM control signal is learned and stored. A control method for a rotating electrical machine.

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