Control device for rotary electric machine device

Abstract

The present invention provides a control device for an AC rotary electric machine, the control device being capable of calculating the voltage command value of a converter that can reduce noise and vibration generated from the rotary electric machine. This control device for a rotary electric machine device sets a noise vibration reduction system voltage as a converter voltage command value. The noise vibration reduction system voltage is a system voltage at which one or both of noise and vibration of a rotary electric machine is smaller than noise vibration at the minimum current generated when the system voltage is controlled to a current minimum system voltage and is smaller than noise vibration at the minimum loss generated when the system voltage is controlled to a loss minimum system voltage.

Description

Control device for rotating electrical machine

[0001] The present disclosure relates to a control device for a rotating electrical machine device.

[0002] Patent Document 1 discloses a rotating electric machine device that controls multiple rotating electric machines by sharing the output voltage of a converter among multiple inverters. The technology in Patent Document 1 focuses on power loss and calculates the power loss of a DC power supply, the power loss of the converter, the power loss of multiple inverters, and the total power loss of these, and determines a voltage that minimizes the total power loss from multiple candidate voltages, and sets the determined voltage as a voltage command value for the converter.

[0003] Patent No. 5652549

[0004] However, the technology of Patent Document 1 only takes into consideration losses and is unable to reduce noise and vibration generated by the rotating electrical machine.

[0005] Therefore, an object of the present disclosure is to provide a control device for an AC rotating electric machine that can calculate a voltage command value for a converter that can reduce noise and vibration generated from the rotating electric machine.

[0006] A control device for a rotating electric machine according to the present disclosure controls a rotating electric machine including a rotating electric machine having windings for multiple phases, a converter capable of outputting a system voltage, which is a DC voltage different from the power supply voltage of a DC power source, to a system voltage line, and an inverter provided between the converter and the rotating electric machine and performing power conversion between DC power from the system voltage line and AC power for driving the rotating electric machine, the control device comprising: a converter voltage command calculation unit that calculates a converter voltage command value; a converter control unit that controls the converter so that the system voltage approaches the converter voltage command value; and an inverter control unit that calculates voltage command values ​​for multiple phases and controls the inverter based on the voltage command values ​​for multiple phases to apply voltages to the windings of the multiple phases, wherein the converter voltage command calculation unit is capable of calculating, when the converter voltage command value is changed within a range from the minimum output voltage to the maximum output voltage that the converter can output, noise and vibration at minimum current, which are one or both of the noise and vibration of the rotating electric machine that occur when the system voltage is controlled to a minimum current system voltage, which is the minimum system voltage required to perform maximum torque current control; The converter voltage command value is set to a noise and vibration reduced system voltage, which is a system voltage at which one or both of the noise and vibration of the rotating electric machine are smaller than the noise and vibration at minimum loss, which is one or both of the noise and vibration of the rotating electric machine generated when the system voltage is controlled to a minimum-loss system voltage, which is a system voltage at which the loss of the evaluation objects, which are one or more of the rotating electric machine, the inverter, and the converter, is minimized.

[0007] According to the control device for a rotating electric machine device of the present disclosure, by setting the converter voltage command value to a noise and vibration reduction system voltage, it is possible to reduce one or both of the noise and vibration of the rotating electric machine more than when the converter voltage command value is set to a current minimum system voltage or a loss minimum system voltage.

[0008] 1 is a configuration diagram of a rotating electric machine device and a control device according to a first embodiment. FIG. 1 is a schematic block diagram of a control device according to the first embodiment. FIG. 2 is a hardware configuration diagram of the control device according to the first embodiment. FIG. 3 is a block diagram of an inverter control unit according to the first embodiment. FIG. 4 is a diagram for explaining carrier wave comparison PWM control according to the first embodiment. FIG. 5 is a diagram for explaining characteristics of changes in current, loss, noise, and vibration with respect to changes in system voltage according to the first embodiment. FIG. 6 is a diagram for explaining changes in characteristics of current, loss, noise, and vibration with respect to changes in torque or rotational angular velocity according to the first embodiment. FIG. 7 is a diagram for explaining changes in a minimum-current system voltage, a minimum-loss system voltage, and a minimum-noise-and-vibration system voltage with respect to changes in torque or rotational angular velocity according to the first embodiment. FIG. 8 is a diagram for explaining a setting method of setting a converter voltage command value to a minimum-current system voltage according to a first comparative example. FIG. 9 is a diagram for explaining a setting method of setting a converter voltage command value to a minimum-loss system voltage according to a second comparative example. FIG. 10 is a configuration diagram of a rotating electric machine device and a control device according to a second embodiment. FIG. 11 is a schematic block diagram of a control device according to the second embodiment. FIG. 12 is a hardware configuration diagram of a control device according to the second embodiment.

[0009] 1. First Embodiment A control device 400 (hereinafter simply referred to as the control device 400) for a rotating electrical machine device 1000 according to a first embodiment will be described with reference to the drawings. Fig. 1 is a schematic configuration diagram of the rotating electrical machine device 1000 and the control device 400 according to the present embodiment.

[0010] The rotating electric machine device 1000 includes a rotating electric machine MG, a converter 15, and an inverter IN. The rotating electric machine MG has windings with multiple phases (three phases in this example). The converter 15 is configured to be able to boost the power supply voltage Vb of the DC power supply B and output it to the system voltage lines 7 and 8. The inverter IN is provided between the converter 15 and the rotating electric machine MG, and performs power conversion between the DC power of the system voltage lines 7 and 8 and the AC power that drives the rotating electric machine MG.

[0011] 1-1. Rotating Electric Machine In this embodiment, the rotating electric machine MG is used as a driving force source for wheels, and the rotating electric machine device 1000 and the control device 400 are mounted on a vehicle.

[0012] The rotating electric machine MG includes a stator fixed to a non-rotating member and a rotor disposed radially inside the stator and rotatably supported. In this embodiment, the rotating electric machine MG is a permanent magnet synchronous rotating electric machine, in which the stator is provided with three-phase windings and the rotor is provided with permanent magnets. The rotating electric machine MG functions as both an electric motor and a generator.

[0013] The rotating electric machine MG is provided with a rotation angle sensor 28 (e.g., a resolver) for detecting the rotation angle θ of the rotor. The output signals of each rotation angle sensor 28 are input to the control device 400. The control device 400 detects the rotation angle θ of the rotating electric machine MG based on the output signals of the rotation angle sensors 28, and calculates the rotation angular velocity ω of the rotating electric machine MG based on the rotation angle θ.

[0014] 1-2. DC Power Supply A secondary battery such as a nickel-metal hydride or lithium ion battery is used as the DC power supply B. An electric double layer capacitor or the like may also be used as the DC power supply B. The positive terminal of the DC power supply B is connected to the power supply positive wire 6 of the converter 15, and the negative terminal of the DC power supply B is connected to the power supply negative wire 5 of the converter 15. A power supply voltage sensor 10 is provided to detect the power supply voltage Vb of the DC power supply B. The output signal of the power supply voltage sensor 10 is input to the control device 400.

[0015] 1-3. Converter The converter 15 is a DC-DC converter connected between the DC power supply B and the system voltage lines 7, 8, and converts DC power. The converter 15 is capable of outputting a system voltage VH, which is a DC voltage different from the power supply voltage Vb of the DC power supply B, to the system voltage lines 7, 8. In this embodiment, the converter 15 is a buck-boost converter having a boost chopper function that boosts the power supply voltage Vb of the DC power supply B and outputs it to the system voltage lines 7, 8, and a buck chopper function that lowers the system voltage VH, which is a DC voltage on the system voltage lines 7, 8, and outputs it to the DC power supply B. The converter 15 includes at least a reactor, a switching element, and a freewheel diode.

[0016] The converter 15 includes a smoothing capacitor C1 connected between the power supply positive electrode wire 6 and the power supply negative electrode wire 5. Between the positive terminal of the DC power supply B and the power supply positive electrode wire 6, and between the negative terminal of the DC power supply B and the power supply negative electrode wire 5, there are provided relays (not shown) that are turned on when the vehicle is operating and turned off when the vehicle is stopped.

[0017] The converter 15 includes a reactor L1, two switching elements Q1 and Q2, two freewheel diodes D1 and D2, and a smoothing capacitor C0. The freewheel diodes D1 and D2 are connected in antiparallel to the two switching elements Q1 and Q2, respectively. The two switching elements Q1 and Q2 are connected in series between a positive system voltage line 7 and a negative system voltage line 8. The reactor L1 is connected between a connection node connecting the two switching elements Q1 and Q2 and the power supply positive wire 6. The smoothing capacitor C0 is connected between the positive system voltage line 7 and the negative system voltage line 8.

[0018] A system voltage sensor 13 is provided between the positive system voltage line 7 and the negative system voltage line 8 to detect a system voltage VH on the system voltage lines 7 and 8. An output signal from the system voltage sensor 13 is input to the control device 400. The two switching elements Q1 and Q2 are on / off controlled by converter control signals S1 and S2 output from the control device 400, respectively.

[0019] 1-4 Inverter The DC voltage side of the inverter IN is connected to the converter 15 via common system voltage lines 7 and 8.

[0020] The inverter IN has three sets of series circuits (legs) corresponding to the three-phase windings. Each set includes a positive-side switching element Q11 (upper arm) connected to the positive-side system voltage line 7 and a negative-side switching element Q12 (lower arm) connected to the negative-side system voltage line 8. Specifically, the inverter IN includes six switching elements: three positive-side switching elements Q11U, Q11V, and Q11W and three negative-side switching elements Q12U, Q12V, and Q12W. Freewheel diodes D11U, D11V, D11W, D12U, D12V, and D12W are connected in anti-parallel to the switching elements Q11U, Q11V, Q11W, Q12U, Q12V, and Q12W, respectively. The connection node between the positive-side switching element Q11 and the negative-side switching element Q12 for each phase is connected to the winding for the corresponding phase of the rotating electric machine MG. A current sensor 27 for detecting the current flowing through the winding of each phase is provided on the electric wire of each phase connecting the connection node of the switching element to the winding. The output signal of the current sensor 27 is input to the control device 400. The on / off of the switching elements Q11U, Q11V, Q11W, Q12U, Q12V, and Q12W is controlled by first inverter control signals S11, S12, S13, S14, S15, and S16 output from the control device 400, respectively.

[0021] The inverter IN converts the DC voltage of the system voltage lines 7 and 8 into a three-phase AC voltage under switching control of the control device 400 and outputs the voltage to the rotating electric machine MG, allowing the rotating electric machine MG to function as an electric motor. Furthermore, the inverter IN converts the three-phase AC voltage generated by the rotating electric machine MG into a DC voltage under switching control of the control device 400 and outputs the DC voltage to the system voltage lines 7 and 8.

[0022] The switching elements of the converter 15 and the inverter IN may be IGBTs (Insulated Gate Bipolar Transistors), power MOS (Metal Oxide Semiconductor) transistors, power bipolar transistors, SiC, GaN, or the like.

[0023] 2, the control device 400 includes functional units such as a converter control unit 750, a converter voltage command calculation unit 700, and an inverter control unit 600. Each function of the control device 400 is realized by a processing circuit included in the control device 400. In this embodiment, as shown in FIG. 3, the control device 400 includes, as processing circuits, an arithmetic processing device 90 (computer) such as a CPU (Central Processing Unit), a storage device 91 that exchanges data with the arithmetic processing device 90, an input circuit 92 that inputs external signals to the arithmetic processing device 90, and an output circuit 93 that outputs signals from the arithmetic processing device 90 to the outside.

[0024] The arithmetic processing device 90 may include an ASIC (Application Specific Integrated Circuit), an IC (Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), various logic circuits, various signal processing circuits, etc. Furthermore, the arithmetic processing device 90 may include a plurality of the same or different types of devices, each performing a different process. The storage device 91 may include a RAM (Random Access Memory) configured to be able to read and write data from the arithmetic processing device 90, a ROM (Read Only Memory) configured to be able to read data from the arithmetic processing device 90, etc. The input circuit 92 is connected to various sensors and switches, such as the power supply voltage sensor 10, the system voltage sensor 13, the current sensor 27, and the rotation angle sensor 28, and includes an A / D converter or the like that inputs output signals from these sensors and switches to the arithmetic processing device 90. The output circuit 93 is connected to electrical loads such as the switching elements of the converter 15 and gate drive circuits that turn on and off the switching elements of the inverter IN, and is equipped with drive circuits that output control signals from the arithmetic processing unit 90 to these electrical loads.

[0025] The functions of the control units 750, 700, 600, etc. included in the control device 400 are realized by the arithmetic processing device 90 executing software (programs) stored in a storage device 91 such as a ROM, and cooperating with other hardware of the control device 400 such as the storage device 91, input circuitry 92, and output circuitry 93. Note that setting data used by the control units 750, 700, 600, etc. is stored in the storage device 91 such as a ROM. Each function of the control device 400 will be described in detail below.

[0026] 1-5-1. Inverter Control Unit 600 The inverter control unit 600 calculates three-phase voltage command values ​​Vu, Vv, and Vw, and controls the inverter IN based on the three-phase voltage command values ​​Vu, Vv, and Vw to apply voltages to the three-phase windings. The inverter control unit 600 controls the on / off of the switching elements of the inverter IN so that the rotating electric machine MG outputs a torque of the torque command value Tqcom. The torque command value Tqcom is transmitted from a control device external to the control device 400 or another control unit internal to the control device 400. In this embodiment, the inverter control unit 600 performs current feedback control using a vector control method.

[0027] The torque command value Tqcom is set to a positive or negative value depending on the operating state.

[0028] As shown in FIG. 4 , the inverter control unit 600 includes a current command calculation unit 610 , a current control unit 640 , a three-phase voltage command calculation unit 650 , a PWM signal generation unit 660 , a current coordinate conversion unit 620 , and a rotational angular velocity detection unit 630 .

[0029] 1-5-1-1 Rotational Angular Velocity Detection Unit 630 The rotational angular velocity detection unit 630 detects the rotational angle θ (magnetic pole position) and rotational angular velocity ω in electrical angle of the rotor of the rotating electrical machine MG based on the output signal of the rotational angle sensor 28 of the rotating electrical machine MG.

[0030] 1-5-1-2. Current Command Calculation Unit 610 <Calculation of d- and q-Axis Current Command Values> The current command calculation unit 610 calculates a d-axis current command value Idcom and a q-axis current command value Iqcom, which are command values ​​for currents to be flowed through the three-phase windings of the rotary electric machine MG, expressed in a rotating coordinate system of the d and q axes of the rotary electric machine MG. The d and q axes rotating coordinate system is a two-axis rotating coordinate system that rotates in synchronization with the rotation of the rotor in electrical angle, and is composed of a d axis defined in the direction of the north pole (magnetic pole position) of a permanent magnet provided in the rotor of the rotary electric machine MG, and a q axis defined in a direction 90° (π / 2) ahead of the d axis in electrical angle.

[0031] <Maximum Torque Current Control, Flux-Weakening Control> The current command calculation unit 610 calculates a d-axis current command value Idcom and a q-axis current command value Iqcom that cause the rotating electric machine MG to output a torque command value Tqcom. The current command calculation unit 610 calculates the d-axis and q-axis current command values ​​Idcom and Iqcom according to a current vector control method such as maximum torque current control or flux-weakening control. In maximum torque current control, the d-axis and q-axis current command values ​​Idcom and Iqcom are calculated that maximize the generated torque for the same current. In flux-weakening control, the d-axis current command value Idcom is increased in the negative direction compared to the d-axis and q-axis current command values ​​Idcom and Iqcom calculated by maximum torque current control, thereby weakening the magnetic flux of the permanent magnet. In the flux-weakening control, the d-axis and q-axis current command values ​​Idcom and Iqcom are moved on a constant induced voltage ellipse (voltage limit ellipse) corresponding to the system voltage VH in accordance with the torque command value Tqcom.

[0032] The current command calculation unit 610 uses map data in which the relationship between the torque command value Tqcom and the dq axis current command values ​​Idcom and Iqcom is preset for each control method, and calculates the dq axis current command values ​​Idcom and Iqcom corresponding to the torque command value Tqcom.

[0033] The current command calculation unit 610 is configured to calculate dq-axis current command values ​​by maximum torque current control under operating conditions where maximum torque current control is possible, and to calculate dq-axis current command values ​​by flux-weakening control under operating conditions where calculation of dq-axis current command values ​​by maximum torque current control is not possible due to limitations of the voltage limit ellipse.

[0034] The current coordinate conversion unit 620 converts the three-phase currents Iu, Iv, Iw flowing through the windings of each phase, detected based on the output signal of the current sensor 27 of the rotating electric machine MG, into a d-axis current Id and a q-axis current Iq expressed in a dq-axis rotating coordinate system by performing a three-phase to two-phase conversion and a rotational coordinate conversion based on the magnetic pole position θ.

[0035] The current control unit 640 performs current feedback control to change a d-axis voltage command value Vd# and a q-axis voltage command value Vq#, which are command signals for voltages to be applied to the rotary electric machine MG and are expressed in a dq-axis rotating coordinate system, by PI control or the like, so that the dq-axis currents Id, Iq approach the dq-axis current command values ​​Idcom, Iqcom.

[0036] 1-5-1-5. Three-Phase Voltage Command Calculation Unit 650 <Coordinate Transformation> The three-phase voltage command calculation unit 650 performs fixed coordinate transformation and two-phase to three-phase transformation on the dq-axis voltage command values ​​Vd#, Vq# based on the magnetic pole position θ, converting them into three-phase voltage command values ​​Vuc, Vvc, Vwc after coordinate transformation. The three-phase voltage command values ​​Vuc, Vvc, Vwc after this coordinate transformation become sine waves and correspond to the three-phase voltage command values ​​or fundamental wave components of the applied voltages to the three-phase windings.

[0037] <Amplitude Reduction Modulation> The three-phase voltage command calculation unit 650 calculates final three-phase voltage command values ​​Vu, Vv, and Vw by applying amplitude reduction modulation to the three-phase voltage command values ​​Vuc, Vvc, and Vwc after coordinate transformation of the sine wave. In the amplitude reduction modulation, offset voltages that reduce the amplitudes of the three-phase voltage command values ​​are added to the three-phase voltage command values, and the line voltages of the three-phase voltage command values ​​are maintained.

[0038] 1-5-1-6. PWM Signal Generator 660 The PWM signal generator 660 turns on and off a plurality of switching elements using PWM (Pulse Width Modulation) control based on three-phase voltage command values ​​Vu, Vv, and Vw. The PWM signal generator 660 compares each of the three-phase voltage command values ​​with a carrier wave to generate a switching signal that turns on and off the switching elements of each phase. The carrier wave is a triangular wave that oscillates with a carrier frequency fc and an amplitude of the system voltage VH / 2, centered on 0.

[0039] In this embodiment, the PWM signal generating unit 660 controls the number C of carrier waves per one electrical angle cycle. One electrical angle cycle is 2π / ω. The PWM signal generating unit 660 changes the carrier frequency fc based on the number C of carrier waves per one electrical angle cycle and the rotational angular velocity ω. fc=C×ω / 2π

[0040] 5, the PWM signal generator 660 turns on the switching signal when the voltage command value exceeds the carrier wave, and turns off the switching signal when the voltage command value falls below the carrier wave. The switching signal is transmitted as is to the switching element on the positive side, and an inverted switching signal is transmitted to the switching element on the negative side. Each switching signal S11 to S16 is input to the gate terminal of each switching element of the inverter IN via a gate drive circuit, turning each switching element on or off.

[0041] 1-5-2. Converter Control Unit 750 When a converter voltage command value VH# (described later) is greater than power supply voltage Vb, converter control unit 750 controls converter 15 so that system voltage VH, which is the DC voltage of system voltage lines 7 and 8, approaches converter voltage command value VH#. In the present embodiment, converter control unit 750 detects power supply voltage Vb based on the output signal of power supply voltage sensor 10, and detects system voltage VH based on the output signal of system voltage sensor 13. Converter control unit 750 changes the duty ratio of converter control signals S1 and S2 in accordance with the PWM control method based on system voltage VH and converter voltage command value VH#.

[0042] When the converter control unit 750 causes the converter 15 to perform a step-up operation, for example, the converter control unit 750 alternates between an on-period in which only the positive-side switching element Q1 is on and an on-period in which only the negative-side switching element Q2 is on, changing the ratio between the two on-periods to change the step-up ratio. When the converter control unit 750 causes the converter 15 to perform a step-down operation, for example, the converter control unit 750 alternates between an on-period in which only the positive-side switching element Q1 is on and an off-period in which all the switching elements Q1 and Q2 are off, changing the ratio between the on-period and the off-period to change the step-down ratio. When the converter voltage command value VH# is equal to or lower than the power supply voltage Vb, the converter control unit 750 turns off all the switching elements Q1 and Q2 and directly connects the DC power supply B to the system voltage lines 7 and 8.

[0043] During a step-up operation, converter 15 steps up power supply voltage Vb supplied from DC power supply B and supplies the system voltage VH to inverter IN in common. During a step-down operation, converter 15 steps down system voltage VH supplied from inverter IN via smoothing capacitor C0 and supplies the system voltage VH to DC power supply B.

[0044] 1-5-3. Converter Voltage Command Calculation Unit 700 Converter voltage command calculation unit 700 calculates converter voltage command value VH#. Converter voltage command calculation unit 700 changes converter voltage command value VH# within the range from the minimum output voltage Vcnmin to the maximum output voltage Vcnmax that the converter can output. In this embodiment, the minimum output voltage Vcnmin is set to the power supply voltage Vb.

[0045] <Principle of Method for Setting Converter Voltage Command Value VH#> The principle of the method for setting the converter voltage command value VH# will be described below. The current, loss, and electromagnetic force of the rotating electric machine when the system voltage VH is changed will be described using Fig. 6. Fig. 6 shows the results of a magnetic field analysis of the current, loss, and electromagnetic force of the rotating electric machine when the system voltage VH is changed in a state in which the rotational angular velocity ω and torque T of the rotating electric machine MG are constant and flux-weakening control is being performed.

[0046] The current of the rotating electric machine is minimum at VH_Imin. VH_Imin is the minimum current system voltage, which is the minimum system voltage required to execute maximum torque current control. In the region where the system voltage VH is less than the minimum current system voltage VH_Imin, flux-weakening control is performed, and as the system voltage VH decreases, the absolute value of the d-axis current increases, and the current of the rotating electric machine increases. In the region where the system voltage VH is equal to or greater than the minimum current system voltage VH_Imin, maximum torque current control is performed, and the current of the rotating electric machine does not generally change in response to changes in the system voltage VH.

[0047] The loss is minimized at VH_LSmin. Here, the loss refers to the loss of one or more of the evaluation targets, which are the rotating electric machine MG, the converter 15, and the inverter IN. In this example, the evaluation targets are all set to the rotating electric machine MG, the converter 15, and the inverter IN. VH_LSmin is the minimum-loss system voltage, which is the system voltage at which the loss of the evaluation target is minimized. As the system voltage VH decreases, the current of the rotating electric machine tends to increase, and therefore, among the losses generated by the rotating electric machine MG, copper loss tends to increase. However, flux-weakening control reduces the iron loss of the rotating electric machine MG and the carrier loss due to PWM control. Furthermore, as the system voltage VH decreases, the increase in the current of the rotating electric machine tends to increase the conduction loss of the inverter IN, but the switching loss of the inverter IN and the converter 15 decreases. Thus, the increase and decrease trends of each loss differ with changes in the system voltage VH, and there exists a system voltage VH at which the total loss is minimized.

[0048] The electromagnetic force generated in the rotating electric machine MG is minimized at VH_NVmin. When the electromagnetic force is minimized, either or both of the noise and vibration of the rotating electric machine are minimized. Therefore, VH_NVmin is the minimum noise and vibration system voltage, which is the system voltage at which either or both of the noise and vibration of the rotating electric machine are minimized.

[0049] <Setting the carrier angular frequency ωc that can effectively reduce noise and vibration> Setting the carrier angular frequency ωc that can effectively reduce noise and vibration will be described. Electromagnetic force is generated by the magnetic flux density generated in the gap formed between the stator and rotor of a rotating electric machine. The magnetic flux density generated in the gap is generated by the magnet of the rotor and the current flowing through the windings of the stator, and for example, the fundamental wave magnetic flux density Bf that contributes to the generation of torque is expressed by equation (1).

[0050] In equation (1), B1 is the magnetic flux density, p is a coefficient, θm is the mechanical angle, ω is the angular frequency of the current, t is the time, and φ1 is the phase.

[0051] The harmonic magnetic flux density Bh, which does not contribute to torque generation, is expressed by the following equation (2): Various components of the harmonic magnetic flux density Bh are generated depending on the number of poles, number of slots, shape, etc. of the rotating electric machine, but equation (2) shows only one example.

[0052] During PWM control, the harmonic components of the current flowing through the stator winding generally include sideband components (ωc±2ω, ωc±4ω) of the carrier angular frequency ωc. The harmonic magnetic flux density Bc generated by these harmonic components of the current is expressed by equation (3).

[0053] Here, the electromagnetic force f is proportional to the square of the magnetic flux density generated in the gap portion, and is therefore expressed as in equation (4).

[0054] By substituting equations (1) to (3) into equation (4), equation (5) is obtained.

[0055] Because the fundamental wave magnetic flux density Bf is the largest magnetic flux density generated in the gap, Equation (5) extracts only the component generated by interaction with the fundamental wave magnetic flux density Bf. 0pθm indicates the spatial zeroth mode, and 2pθm indicates the spatial 2pth mode. Focusing on the spatial zeroth mode (0pθm), when the carrier angular frequency ωc = 9ω or ωc = 3ω, the time order of the spatial zeroth mode in the third to sixth terms of Equation (5) is 6ω, as in the first and second terms of Equation (5), resulting in multiple terms of electromagnetic forces of the same time order. Therefore, the amplitude and phase relationship between these components of the same spatial order and time order results in amplification or cancellation of the electromagnetic force. When the system voltage VH changes, the harmonic components of each order of the current flowing through the stator winding change, which in turn changes the harmonic magnetic flux density Bc of each order, changing the balance between amplification and cancellation. Therefore, there exists a system voltage VH at which the electromagnetic force is minimized. Since electromagnetic force causes noise and vibration, selecting a system voltage VH that minimizes the electromagnetic force can reduce either or both of the noise and vibration. The control method of selecting a system voltage VH that minimizes the electromagnetic force is called noise and vibration minimum setting. Note that while the focus here is on the spatial zeroth mode, the same applies to other modes.

[0056] Generalizing equation (5) with a focus on the spatial zeroth mode, the first and second terms of equation (5) show that if the number of phases of the rotating electric machine is B, then in the spatial zeroth mode, an electromagnetic force of B×2a order (a is a natural number) is generated, regardless of the carrier angular frequency ωc. From the third to fifth terms of equation (5), if the number of carrier waves per electrical angle cycle is C (ωc = C×ω), then in the spatial zeroth mode, an electromagnetic force of n×C+3m order (n is a natural number, m is an integer) is generated, depending on the carrier angular frequency ωc. The condition under which these conditions are met is B×2a=n×C+3m. Among multiple candidates for the number C of carrier waves that satisfy this condition, it is sufficient to select a number C of carrier waves that satisfies the condition and effectively reduces the electromagnetic force with respect to changes in the system voltage VH. For example, C is selected from multiples of B, and m corresponds to a sideband and is therefore selected from m = ±1 or ±2.

[0057] <Changes in each minimum system voltage with respect to changes in torque and rotational angular velocity ω> Figures 7 and 8 show schematic diagrams of changes in the current minimum system voltage VH_Imin, loss minimum system voltage VH_LSmin, and noise and vibration minimum system voltage VH_NVmin when the torque T or rotational angular velocity ω increases. As the torque or rotational angular velocity ω increases, the minimum system voltages VH_Imin, VH_LSmin, and VH_NVmin monotonically increase. In the examples of Figures 7 and 8, VH_LSmin < VH_NVmin < VH_Imin. Depending on the target of loss evaluation and the characteristics of noise and vibration, VH_LSmin and VH_NVmin may be interchanged.

[0058] When all the minimum system voltages are equal to or less than the power supply voltage Vb, the system voltage VH (converter voltage command value VH#) is set to the power supply voltage Vb. On the other hand, when all the minimum system voltages are equal to or greater than the maximum output voltage Vcnmax, the system voltage VH (converter voltage command value VH#) is set to the maximum output voltage Vcnmax.

[0059] <Method for Setting Converter Voltage Command Value VH# According to Comparative Example> A method for setting the converter voltage command value VH# according to a first comparative example will be described. In the first comparative example, when the converter voltage command value VH# is changed within the range from the minimum output voltage Vcnmin to the maximum output voltage Vcnmax, the minimum current system voltage VH_Imin is set as the converter voltage command value VH#. FIG. 9 shows how the converter voltage command value VH# is set with respect to changes in the rotational angular velocity ω under the condition that the torque T is constant. As the rotational angular velocity ω increases, the minimum current system voltage VH_Imin increases. In the range of rotational angular velocity (ωa1 or less) where the minimum current system voltage VH_Imin is equal to or less than the minimum output voltage Vcnmin (power supply voltage Vb in this example), the minimum output voltage Vcnmin (power supply voltage Vb) is set as the converter voltage command value VH#. In a range of rotational angular velocities (above ωa2) where the minimum current system voltage VH_Imin is equal to or greater than the maximum output voltage Vcnmax, the maximum output voltage Vcnmax is set as the converter voltage command value VH#. In a range of rotational angular velocities (from ωa1 to ωa2) where the minimum current system voltage VH_Imin is within the range from the minimum output voltage Vcnmin to the maximum output voltage Vcnmax, the minimum current system voltage VH_Imin is set as the converter voltage command value VH#. ωa1 and ωa2 decrease as the absolute value of torque T increases. In a range of rotational angular velocities (below ωa2) where the converter voltage command value VH# (system voltage VH) is equal to or greater than the minimum current system voltage VH_Imin, maximum torque current control is performed. In a range of rotational angular velocities (greater than ωa2) where the converter voltage command value VH# (system voltage VH) is less than the minimum current system voltage VH_Imin, flux-weakening control is performed.

[0060] A method for setting the converter voltage command value VH# according to a second comparative example will be described. In the second comparative example, when the converter voltage command value VH# is changed within the range from the minimum output voltage Vcnmax to the maximum output voltage Vcnmax, a minimum-loss system voltage VH_LSmin is set as the converter voltage command value VH#. FIG. 10 shows how the converter voltage command value VH# is set with respect to a change in the rotational angular velocity ω under the condition that the torque T is constant. As the rotational angular velocity ω increases, the minimum-loss system voltage VH_LSmin increases. In a rotational angular velocity range (ωb1 or less) where the minimum-loss system voltage VH_LSmin is equal to or less than the minimum output voltage Vcnmax (power supply voltage Vb), the minimum output voltage Vcnmax (power supply voltage Vb) is set as the converter voltage command value VH#. In a rotational angular velocity range (ωb2 or more) where the minimum-loss system voltage VH_LSmin is equal to or greater than the maximum output voltage Vcnmax, the maximum output voltage Vcnmax is set as the converter voltage command value VH#. In a rotational angular velocity range (ωb1 to ωb2) where the minimum-loss system voltage VH_LSmin is within the range from the minimum output voltage Vcnmin to the maximum output voltage Vcnmax, the minimum-loss system voltage VH_LSmin is set as the converter voltage command value VH#. ωb1 and ωb2 decrease as the absolute value of the torque T increases. In a rotational angular velocity range where the converter voltage command value VH# (system voltage VH) is equal to or greater than the minimum current system voltage VH_Imin, maximum torque current control is performed, and in a rotational angular velocity range where the converter voltage command value VH# (system voltage VH) is less than the minimum current system voltage VH_Imin, flux-weakening control is performed.

[0061] <Method of Setting Converter Voltage Command Value VH# According to This Embodiment> In this embodiment, when converter voltage command value VH# is changed within a range from minimum output voltage Vcnmin (power supply voltage Vb in this example) to maximum output voltage Vcnmax, converter voltage command calculation unit 700 sets, as converter voltage command value VH#, a noise and vibration reduced system voltage VH_NVlow that is a system voltage at which one or both of the noise and vibration of the rotating electric machine are smaller than the noise and vibration at minimum current, which is one or both of the noise and vibration of the rotating electric machine that occur when system voltage VH is controlled to minimum current system voltage VH_Imin, and the noise and vibration at minimum loss, which is one or both of the noise and vibration of the rotating electric machine that occur when system voltage VH is controlled to minimum loss system voltage VH_LSmin.

[0062] According to this configuration, by setting the converter voltage command value VH# to the noise and vibration reduction system voltage VH_NVlow, it is possible to reduce one or both of the noise and vibration of the rotating electric machine more than when the converter voltage command value VH# is set to the minimum current system voltage VH_Imin or the minimum loss system voltage VH_LSmin.

[0063] The noise and vibration reduced system voltage VH_NVlow is set to a system voltage that is closer to the noise and vibration reduced system voltage VH_NVmin than the current minimum system voltage VH_Imin and the loss minimum system voltage VH_LSmin. For example, the voltage may be set to a value that balances loss reduction, current reduction, and noise and vibration reduction.

[0064] In this embodiment, when the converter voltage command value VH# is changed within the range from the minimum output voltage Vcnmin (power supply voltage Vb) to the maximum output voltage Vcnmax, the converter voltage command calculation unit 700 sets the minimum noise and vibration system voltage VH_NVmin, which is the system voltage at which either or both of the noise and vibration of the rotating electric machine are minimized, as the converter voltage command value VH#.

[0065] This configuration makes it possible to minimize either or both of the noise and vibration of the rotating electrical machine.

[0066] FIG. 11 shows how converter voltage command value VH# is set with respect to changes in rotational angular velocity ω, with torque T held constant. As rotational angular velocity ω increases, minimum system noise and vibration voltage VH_NVmin increases. In a range of rotational angular velocity (ωc1 or less) where minimum system noise and vibration voltage VH_NVmin is equal to or less than minimum output voltage Vcnmin (power supply voltage Vb), the minimum output voltage Vcnmin (power supply voltage Vb) is set as converter voltage command value VH#. In a range of rotational angular velocity (ωc2 or more) where minimum system noise and vibration voltage VH_NVmin is equal to or greater than maximum output voltage Vcnmax, the maximum output voltage Vcnmax is set as converter voltage command value VH#. In a range of rotational angular velocity (ωc1 to ωc2) where minimum system noise and vibration voltage VH_NVmin is between the minimum output voltage Vcnmin and the maximum output voltage Vcnmax, the minimum system noise and vibration voltage VH_NVmin is set as converter voltage command value VH#. ωc1 and ωc2 decrease as the absolute value of the torque command value Tqcom increases. Maximum torque current control is performed in a range of rotational angular speeds where the converter voltage command value VH# (system voltage VH) is equal to or greater than the minimum current system voltage VH_Imin, and flux-weakening control is performed in a range of rotational angular speeds where the converter voltage command value VH# (system voltage VH) is less than the minimum current system voltage VH_Imin.

[0067] <Setting Based on Rotational Speed ​​and Torque> Converter voltage command calculation unit 700 calculates converter voltage command value VH#, which is set to noise and vibration minimum system voltage VH_NVmin (or noise and vibration reduced system voltage VH_NVlow), based on the rotational speed and torque of the rotating electric machine.

[0068] For example, a voltage command value setting map, as shown in Fig. 11 , in which the relationship between the rotational angular velocity ω and the converter voltage command value VH# set to the noise and vibration minimum system voltage VH_NVmin (or the noise and vibration reduction system voltage VH_NVlow) is set in advance, is stored in a storage device such as a ROM for each of a plurality of torque command values ​​Tqcom. Converter voltage command calculation unit 700 then references the voltage command value setting map corresponding to the current torque command value Tqcom and sets converter voltage command value VH# corresponding to the current rotational angular velocity ω.

[0069] Alternatively, a voltage command value setting map is stored in a storage device such as a ROM, in which the relationship between the rotational angular velocity ω, the torque command value Tqcom, and the converter voltage command value VH# set to the noise and vibration minimum system voltage VH_NVmin (or the noise and vibration reduced system voltage VH_NVlow) is set in advance. Converter voltage command calculation unit 700 sets converter voltage command value VH# corresponding to the current rotational angular velocity ω and the current torque command value Tqcom by referring to the voltage command value setting map.

[0070] <Setting the Number of Carrier Waves Per Electrical Angle Cycle> The number C of carrier waves per electrical angle cycle is set to a natural number that can reduce either or both of the noise and vibration of the rotating electric machine by changing the system voltage VH.

[0071] According to this configuration, as described above, the harmonic magnetic flux density generated by the current components of the sideband waves of the carrier angular frequency can effectively cancel out the harmonic magnetic flux density generated by the winding current, thereby enhancing the effect of reducing noise and vibration.

[0072] In this embodiment, a candidate for the number of carrier waves is Ctmp, the number of phases is B, n is a natural number, m is an integer, and a is a natural number, and among a plurality of Ctmps for which B×2×a=n×Ctmp+3×m holds, a natural number that can reduce either or both of the noise and vibration of the rotating electric machine by changing the system voltage VH is set as the number C of carrier waves per one electrical angle cycle. For example, C is selected from multiples of B, and m corresponds to sideband waves and is therefore selected from m=±1 and ±2.

[0073] According to this configuration, as described above, in the spatial zero-order mode, an electromagnetic force of the B×2a order time order is generated regardless of the carrier angular frequency ωc, and in the spatial zero-order mode, an electromagnetic force of the n×Ctmp+3m order time order is generated in relation to the carrier angular frequency ωc, so that, of the multiple Ctmp values ​​that match these, a natural number that can reduce noise and vibration of the rotating electric machine by changing the system voltage VH is set as the number of carrier waves C. Therefore, taking into account the frequencies of the sideband waves of the carrier angular frequency, it is possible to accurately set the number C of carrier waves that can enhance the noise and vibration reduction effect.

[0074] Furthermore, a candidate for the number of carrier waves may be Ctmp, the least common multiple of the number of poles and the number of slots of the rotating electric machine may be K, the number of pole pairs of the rotating electric machine may be P, m may be an integer, and a may be a natural number, and among multiple Ctmps for which K / P = n × Ctmp + 3 × m holds, a natural number that can reduce either or both of the noise and vibration of the rotating electric machine due to changes in the system voltage VH may be set as the number C of carrier waves per one electrical angle cycle. Similarly, for example, C is selected from multiples of B, and m corresponds to sideband waves and is therefore selected from m = ±1 or ±2.

[0075] In the spatial zeroth mode, of the electromagnetic forces of the time order of B×2a, which are unrelated to the carrier angular frequency ωc, the electromagnetic force of the time order of K / P is the largest. Therefore, by setting the number C of carrier waves to a natural number that can reduce the noise and vibration of the rotating electrical machine by changing the system voltage VH, out of multiple Ctmp values ​​for which K / P = n×Ctmp + 3×m holds, the effect of reducing noise and vibration can be enhanced.

[0076] For example, in the case of a three-phase, eight-pole, twelve-slot rotating electric machine, K / P = 6th order; in the case of a three-phase, ten-pole, twelve-slot rotating electric machine, K / P = 12th order; in the case of a three-phase, eight-pole, nine-slot rotating electric machine, K / P = 18th order; in the case of a three-phase, eight-pole, 48-slot rotating electric machine, K / P = 12th order; and in the case of a five-phase, eight-pole, 20-slot rotating electric machine, K / P = 10th order.

[0077] As described above, the source of either or both of the noise and vibration of a rotating electrical machine that is reduced by setting the number C of carrier waves per one electrical angle cycle is the electromagnetic force of the spatial zeroth mode.

[0078] According to this configuration, by setting the number C of carrier waves that can reduce the electromagnetic force of the spatial zeroth mode, which increases noise and vibration, the effect of reducing noise and vibration by setting the converter voltage command value VH# can be enhanced.

[0079] <Switching of Setting Modes> Converter voltage command calculation unit 700 may be configured to determine which of a plurality of setting modes, including the first mode, to execute. If converter voltage command calculation unit 700 determines to execute the first mode, it sets the minimum noise and vibration system voltage VH_NVmin (or noise and vibration reduced system voltage VH_NVlow) as the converter voltage command value VH#. If converter voltage command calculation unit 700 determines to execute a setting mode other than the first mode, it sets, as converter voltage command value VH#, a noise and vibration increasing system voltage that reduces the loss or the current of the rotating electric machine to be evaluated and increases one or both of the noise and vibration of the rotating electric machine compared to the case of the minimum noise and vibration system voltage VH_NVmin (or noise and vibration reduced system voltage VH_NVlow).

[0080] With this configuration, it is possible to switch between a first mode that reduces noise and vibration and another set mode that reduces losses or the current of the rotating electric machine, and to strike a balance between the two depending on the purpose or need.

[0081] A second mode and a third mode may be provided as setting modes other than the first mode. In the second mode, a loss-reduced system voltage (or a loss-minimum system voltage VH_LSmin) that is a system voltage at which the loss to be evaluated is reduced compared to the case of the minimum noise and vibration system voltage VH_NVmin (or the noise and vibration-reduced system voltage VH_NVlow) and at which one or both of the noise and vibration of the rotating electric machine increase may be set as the converter voltage command value VH#. In the third mode, a current-reduced system voltage (or a current-minimum system voltage VH_Imin) that is a system voltage at which the current of the rotating electric machine is reduced compared to the case of the minimum noise and vibration system voltage VH_NVmin (or the noise and vibration-reduced system voltage VH_NVlow) and at which one or both of the noise and vibration of the rotating electric machine increase may be set as the converter voltage command value VH#.

[0082] For example, converter voltage command calculation unit 700 determines which of a plurality of setting modes including the first mode to execute based on the rotational angular velocity ω of the rotating electric machine and the torque command value Tqcom.

[0083] For example, converter voltage command calculation unit 700 may determine to execute the first mode when the rotational angular velocity ω of the rotating electric machine is within a resonance determination range that includes the resonant rotational angular velocity of the rotating electric machine, and may determine to execute a setting mode other than the first mode when the rotational angular velocity ω of the rotating electric machine is outside the resonance determination range. When resonance occurs, noise and vibration are amplified and become particularly problematic, so noise and vibration can be effectively reduced. In other cases, effects other than the reduction of noise and vibration can be enhanced.

[0084] Furthermore, when the rotational angular velocity ω of the rotating electric machine is outside the resonance determination range, the converter voltage command calculation unit 700 may determine to execute the third mode when the rotational angular velocity ω of the rotating electric machine and the torque command value Tqcom are higher than the determination value, indicating a high output, and may determine to execute the second mode when the rotational angular velocity ω of the rotating electric machine and the torque command value Tqcom are lower than the determination value. In the case of high output, a system voltage can be set that emphasizes increasing output, and in the case of low output, a system voltage can be set that emphasizes reducing losses.

[0085] Alternatively, converter voltage command calculation unit 700 may determine which of a plurality of set modes including the first mode to execute in response to a command from an external device. For example, the external device accepts a selection of a plurality of operation modes, such as a power saving (economy) mode, a high output mode, or a low noise and vibration mode, by a user (e.g., a driver) via a user interface, and transmits the accepted operation mode to control device 400.

[0086] Then, converter voltage command calculation unit 700 determines to execute the first mode when the low noise and vibration mode is selected. Converter voltage command calculation unit 700 determines to execute the second mode when the power saving mode is selected. Converter voltage command calculation unit 700 determines to execute the third mode when the high output mode is selected. Note that even when the power saving mode or the high output mode is selected, converter voltage command calculation unit 700 may determine to execute the first mode when the rotational angular velocity ω of the rotating electric machine is within the resonance determination range.

[0087] 2. Second Embodiment Next, a rotating electric machine device 1000 and a control device 400 according to a second embodiment will be described. Description of components similar to those in the first embodiment will be omitted. The basic configuration of the rotating electric machine device 1000 and the control device 400 according to this embodiment is similar to that of the first embodiment, but in this embodiment, multiple sets of rotating electric machines and inverters are provided, and therefore the processing of the control device 400 is different. Figure 12 is a schematic configuration diagram of the rotating electric machine device 1000 and the control device 400 according to this embodiment.

[0088] In this embodiment, multiple pairs (two pairs in this example) of rotating electric machines MG and inverters IN are provided. Each of the first and second rotating electric machines MG1 and MG2 functions as both an electric motor and a generator. For example, the first rotating electric machine MG1 operates as a generator driven by an internal combustion engine (not shown) and also operates as an electric motor that starts the internal combustion engine. The second rotating electric machine MG2 is connected to wheels via an output shaft and a reduction gear (not shown) and operates as an electric motor that drives the wheels and also as a generator that regenerates electricity using the driving force of the wheels. The DC voltage sides of the first inverter IN1 and the second inverter IN2 are connected to a converter 15 via common system voltage lines 7 and 8.

[0089] The configurations of the first and second rotating electric machines MG1 and MG2 are similar to the configuration of the rotating electric machine MG in the first embodiment, and therefore descriptions thereof will be omitted. The configurations of the first and second inverters IN1 and IN2 are similar to the configuration of the inverter IN in the first embodiment, and therefore descriptions thereof will be omitted.

[0090] Fig. 13 shows a block diagram of the control device 400 according to this embodiment, and Fig. 14 shows a hardware configuration diagram of the control device 400 according to this embodiment.

[0091] In this embodiment, the inverter control unit 600 includes a first inverter control unit 600a that controls the first inverter IN1 and the first rotating electric machine MG1, and a second inverter control unit 600b that controls the second inverter IN2 and the second rotating electric machine MG2. The configurations of the inverter control units 600a and 600b are similar to the configuration of the inverter control unit 600 in the first embodiment, and therefore description thereof will be omitted.

[0092] <Converter voltage command calculation unit 700> In the present embodiment, when converter voltage command value VH# is changed within the range from minimum output voltage Vcnmin to maximum output voltage Vcnmax, converter voltage command calculation unit 700 sums, for all groups, the noise and vibration characteristics that represent changes in the magnitude of either or both of the noise and vibration in response to changes in the system voltage set for each group of rotating electric machines, and sets, as converter voltage command value VH#, a total minimum noise and vibration system voltage VH_NVminall that is the system voltage at which either or both of the noise and vibration are minimum based on the summed noise and vibration characteristics.

[0093] The noise and vibration characteristics of each set are set as a polynomial with the system voltage VH as an input variable and the magnitude NV of one or both of the noise and vibration as an output variable, and the converter voltage command calculation unit 700 sums the polynomials of each set to calculate the total noise and vibration characteristics.

[0094] For example, the second-order polynomial of equation (6) is used as the noise and vibration characteristics of the first rotating electric machine, the second-order polynomial of equation (7) is used as the noise and vibration characteristics of the second rotating electric machine, and the second-order polynomial of equation (8) is used as the total noise and vibration characteristics obtained by adding together equations (6) and (7).

[0095] Converter voltage command calculation unit 700 refers to a coefficient setting map in which the relationships between the rotational angular velocity ω1 of the first rotating electric machine, the torque T1 of the first rotating electric machine, and the coefficients α1, β1, γ1 of each order of the polynomial of the first rotating electric machine are preset, and calculates coefficients α1, β1, γ1 corresponding to the current rotational angular velocity ω1 of the first rotating electric machine and the current torque command value Tqcom1 of the first rotating electric machine. Converter voltage command calculation unit 700 also refers to a coefficient setting map in which the relationships between the rotational angular velocity ω2 of the second rotating electric machine, the torque T2 of the second rotating electric machine, and the coefficients α2, β2, γ2 of each order of the polynomial of the second rotating electric machine are preset, and calculates coefficients α2, β2, γ2 corresponding to the current rotational angular velocity ω2 of the second rotating electric machine and the current torque command value Tqcom2 of the second rotating electric machine.

[0096] As shown in equation (9), converter voltage command calculation unit 700 calculates the minimum value of the total noise and vibration characteristics as total noise and vibration minimum system voltage VH_NVminall.

[0097] Converter voltage command calculation unit 700 sets total noise and vibration minimum system voltage VH_NVminall as converter voltage command value VH# when total noise and vibration minimum system voltage VH_NVminall is within the range from minimum output voltage Vcnmin to maximum output voltage Vcnmax. Converter voltage command calculation unit 700 sets minimum output voltage Vcnmin as converter voltage command value VH# when total noise and vibration minimum system voltage VH_NVminall is equal to or less than the minimum output voltage Vcnmin. Converter voltage command calculation unit 700 sets maximum output voltage Vcnmax as converter voltage command value VH# when total noise and vibration minimum system voltage VH_NVminall is equal to or greater than the maximum output voltage Vcnmax.

[0098] As in the first embodiment, when the second mode is executed, converter voltage command value VH# may be set to minimum total loss system voltage VH_LSminall. Converter voltage command calculation unit 700 sums, for all pairs, loss characteristics that represent changes in losses to be evaluated relative to changes in system voltages set for the rotating electric machines of each pair, and sets, as converter voltage command value VH#, minimum total loss system voltage VH_LSminall, which is the system voltage at which losses are minimized in the summed loss characteristics. In this case, as in the case of noise and vibration characteristics, calculation is performed using a polynomial for each pair that represents the loss characteristics.

[0099] As in the first embodiment, when the third mode is executed, converter voltage command value VH# may be set to total current minimum system voltage VH_Iminall. Converter voltage command calculation unit 700 sums, for all pairs, the current characteristics that represent changes in current relative to changes in system voltage set for each pair of rotating electric machines, and sets total current minimum system voltage VH_Iminall, which is the system voltage at which the current is minimum in the summed current characteristics, as converter voltage command value VH#. In this case, as in the case of the noise and vibration characteristics, calculation is performed using the polynomial for each pair that represents the current characteristic.

[0100] Other Embodiments (1) In the above embodiments, one or two sets of rotating electric machines MG and inverters IN are provided, and the control device 400 is configured to accommodate the one or two sets. However, three or more sets of rotating electric machines MG and inverters IN may be provided. The control device 400 is configured appropriately to accommodate the number of sets.

[0101] (2) In the above embodiments, the rotating electrical machine device 1000 is mounted on a hybrid vehicle. However, the rotating electrical machine device 1000 may be mounted on an electric vehicle or used as a driving power source for devices other than a hybrid vehicle.

[0102] (3) In the above embodiments, the minimum output voltage Vcnmin of converter 15 is set to the power supply voltage Vb. However, for example, when converter 15 performs a step-down operation, the minimum output voltage Vcnmin may be set to a voltage higher than the power supply voltage Vb.

[0103] (4) In the above embodiments, the noise and vibration minimum system voltage VH_NVmin (or the noise and vibration reduced system voltage VH_NVlow) is set taking into consideration noise and vibration due to spatial modes caused by electromagnetic forces in the radial direction. However, noise and vibration due to electromagnetic forces in one or more of the radial direction, the circumferential direction (torque ripple), and the axial direction may also be taken into consideration.

[0104] (5) In the above embodiments, the PWM signal generating unit 660 performs synchronous control to control the number C of carrier waves per one electrical angle cycle. However, the PWM signal generating unit 660 may perform synchronous control only when the minimum noise and vibration system voltage VH_NVmin (or the noise and vibration reduction system voltage VH_NVlow) is set to the converter voltage command value VH#, and may perform asynchronous control in other cases in which the number C of carrier waves per one electrical angle cycle is not controlled and the carrier angular frequency ωc is not changed in accordance with the rotational angular velocity.

[0105] (6) In the above embodiments, converter 15 has been described as including a series circuit of two switching elements. However, other types of converters may be used as converter 15 as long as they are DC / DC converters that can output a system voltage, which is a DC voltage different from the power supply voltage of the DC power supply, to a system voltage line.

[0106] Although various exemplary embodiments and examples are described in this disclosure, the various features, aspects, and functions described in one or more embodiments are not limited to the application of a particular embodiment, but may be applied to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are contemplated within the scope of the technology disclosed in this disclosure specification. For example, this includes cases where at least one component is modified, added, or omitted, or where at least one component is extracted and combined with components of another embodiment.

[0107] 15: Converter, 400: Control device for rotating electric machine device, 600: Inverter control unit, 700: Converter voltage command calculation unit, 750: Converter control unit, IN: Inverter, MG: Rotating electric machine, VH: System voltage, VH#: Converter voltage command value, VH_Imin: Minimum current system voltage, VH_LSmin: Minimum loss system voltage, VH_NVlow: Noise and vibration reduced system voltage, VH_NVmin: Minimum noise and vibration system voltage, Vb: Power supply voltage, Vcnmax: Maximum output voltage, Vcnmin: Minimum output voltage, C: Number of carrier waves per electrical angle cycle

Claims

1. A control device for a rotating electric machine comprising: a rotating electric machine having multiple phase windings; a converter capable of outputting a system voltage, which is a DC voltage different from the power supply voltage of a DC power source, to a system voltage line; and an inverter provided between the converter and the rotating electric machine, which performs power conversion between the DC power of the system voltage line and the AC power that drives the rotating electric machine, wherein the control device for the rotating electric machine comprises: A converter voltage command calculation unit that calculates the converter voltage command value, A converter control unit controls the converter so that the system voltage approaches the converter voltage command value, The system includes an inverter control unit that calculates voltage command values ​​for multiple phases and controls the inverter based on the voltage command values ​​for multiple phases to apply voltage to the windings of the multiple phases, The converter voltage command calculation unit is: When the converter voltage command value is changed within the range from the minimum output voltage to the maximum output voltage that the converter can output, Noise and vibration at minimum current, which are one or both of the noise and vibration of the rotating electric machine that occur when the system voltage is controlled to the minimum current system voltage, which is the minimum system voltage required to perform maximum torque current control, and Noise and vibration at minimum loss, which occur when the system voltage is controlled to the minimum loss system voltage, which is the system voltage at which the loss of one or more of the equipment being evaluated, namely the rotating electric machine, the inverter, and the converter, is minimized, are one or both of the noise and vibration of the rotating electric machine. A control device for a rotating electric machine, which sets a noise and vibration reduction system voltage as the converter voltage command value, which is a system voltage that reduces one or both of the noise and vibration of the rotating electric machine compared to the standard voltage.

2. The converter voltage command calculation unit is: When the converter voltage command value is changed within the range from the minimum output voltage to the maximum output voltage that the converter can output, The control device for a rotating electric machine according to claim 1, wherein the noise and vibration minimum system voltage, which is the system voltage at which one or both of the noise and vibration of the rotating electric machine are minimized, is set as the converter voltage command value.

3. The inverter control unit controls the switching elements of the inverter by turning them on and off based on the comparison result between the carrier wave and the voltage command value. The control device for a rotating electric machine according to claim 1, wherein the number of carrier waves per electrical angle period is set to a natural number that reduces either or both of the noise and vibration of the rotating electric machine by changing the system voltage.

4. Let Ctmp be the candidate number of carrier waves, B be the number of phases, n be a natural number, m be an integer, and a be a natural number. B × 2 × a = n × Ctmp + 3 × m The control device for a rotating electric machine according to claim 3, wherein among a plurality of Ctmp such that the above condition is met, a natural number that can reduce either or both the noise and vibration of the rotating electric machine by changing the system voltage is set as the number of carrier waves per period of the electrical angle.

5. Let Ctmp be the candidate number of carrier waves, K be the least common multiple of the number of poles and slots of the rotating electric machine, P be the number of pole pairs of the rotating electric machine, m be an integer, and a be a natural number. K / P=n×Ctmp+3×m The control device for a rotating electric machine according to claim 3, wherein among a plurality of Ctmp such that the above condition is met, a natural number that can reduce either or both the noise and vibration of the rotating electric machine by changing the system voltage is set as the number of carrier waves per period of the electrical angle.

6. The control device for a rotating electric machine according to any one of claims 3 to 5, wherein the source of one or both of the noise and vibration of the rotating electric machine, which are reduced by setting the number of carrier waves per period of the electrical angle, is an electromagnetic force of the 0th order in space.

7. The control device for a rotating electric machine according to any one of claims 1 to 5, wherein the converter voltage command calculation unit calculates the converter voltage command value to be set as the noise and vibration reduction system voltage based on the rotational speed and torque of the rotating electric machine.

8. The converter voltage command calculation unit determines which of a plurality of setting modes, including the first mode, to execute. If it is determined that the first mode will be executed, the noise and vibration reduction system voltage is set as the converter voltage command value. A control device for a rotating electric machine according to any one of claims 1 to 5, wherein, if it is determined to execute a setting mode other than the first mode, a noise and vibration increasing system voltage is set as the converter voltage command value, which is a system voltage at which the loss to be evaluated or the current of the rotating electric machine decreases compared to the noise and vibration reduction system voltage, and one or both of the noise and vibration of the rotating electric machine increase.

9. The control device for a rotating electric machine according to claim 8, wherein the converter voltage command calculation unit determines which of the plurality of setting modes, including the first mode, to execute in response to a command from an external device.

10. The control device for a rotating electric machine according to claim 8, wherein the converter voltage command calculation unit determines which of the plurality of setting modes, including the first mode, to execute based on the rotational speed and torque of the rotating electric machine.

11. The control device for a rotating electric machine according to claim 8, wherein the converter voltage command calculation unit determines to execute the first mode when the rotational speed of the rotating electric machine is within a resonance determination range that includes the resonant rotational speed of the rotating electric machine, and determines to execute a setting mode other than the first mode when the rotational speed of the rotating electric machine is outside the resonance determination range.

12. Multiple sets of the aforementioned rotating electric machine and inverter are provided. The converter voltage command calculation unit is: When the converter voltage command value is changed within the range from the minimum output voltage to the maximum output voltage that the converter can output, A control device for a rotating electric machine according to any one of claims 1 to 5, wherein the noise and vibration characteristics representing the change in magnitude of one or both noise and vibration in response to a change in the system voltage set for each set of rotating electric machines are summed up for all sets, and the total noise and vibration minimum system voltage, which is the system voltage at which one or both noise and vibration are minimized in the summed noise and vibration characteristics, is set as the converter voltage command value.