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

Abstract

A first H vector (VaH) of which the voltage level is an H level, a second H vector (VbH) of which the voltage level is an H level, a first L vector (VaL) of which the voltage level is an L level, a second L vector (VbL) of which the voltage level is an L level, and an M vector (VM) of which the voltage level is an M level are defined as space vectors for H-drive control. A control device (70) includes at least three vectors from among the first H vector, the second H vector, the M vector, the first L vector, and the second L vector in a switching pattern for each prescribed period.

Description

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

[0001] This application is based on Japanese Application No. 2023-219448 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 program, and a control method for a rotating electric machine.

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

[0004] Patent No. 7361222

[0005] The control device performs H drive control, which PWM-drives each switch included in the first and second inverters. Specifically, the control device performs H drive control in which the voltage vector applied to the armature winding includes a zero voltage vector and an effective voltage vector. During the zero voltage vector period, no current flows from the DC power supply to the first and second inverters, so the capacitor connected to the first inverter is charged from the DC power supply. On the other hand, during the effective voltage vector period, the capacitor is discharged. As the capacitor is repeatedly charged and discharged, a ripple component is included in the current flowing through the capacitor.

[0006] Depending on the operating point of the rotating electrical machine, the period of the zero voltage vector may become long, which increases the current ripple flowing through the capacitor and increases the amount of heat generated by the capacitor.

[0007] A primary object of the present disclosure is to provide a control device for a rotating electric machine, a program, and a control method for a rotating electric machine that can reduce current ripple flowing through a capacitor.

[0008] The present disclosure relates to a control device for a rotating electric machine that is applied to a system including: a rotating electric machine having a multi-phase armature winding; a first inverter having first upper arm switches and first lower arm switches connected in series for the same number of phases, and a series-connected assembly of the first upper arm switches and the first lower arm switches connected in parallel to a DC power source; a second inverter having second upper arm switches and second lower arm switches connected in series for the same number of phases; a positive bus bar that electrically connects, in each phase, a high potential side terminal of the first upper arm switch and a high potential side terminal of the second upper arm switch; a negative bus bar that electrically connects, in each phase, a low potential side terminal of the first lower arm switch and a low potential side terminal of the second lower arm switch; and a capacitor connected in parallel to the series-connected assembly of the first upper arm switch and the first lower arm switch, In each phase, a low potential side terminal of the second upper arm switch and a high potential side terminal of the second lower arm switch are electrically connected to a second end of the armature winding, and in an H drive control that PWM drives the first upper arm switch, the first lower arm switch, the second upper arm switch and the second lower arm switch, the H drive control includes: a setting unit that sets a switching pattern for the first upper arm switch, the first lower arm switch, the second upper arm switch and the second lower arm switch for each specified period; and a switch control unit that controls the on / off of the first upper arm switch, the first lower arm switch, the second upper arm switch and the second lower arm switch based on the set switching pattern.

[0009] The spatial vectors defined in the H drive control are: a zero voltage vector; a first H vector, which is a voltage vector extending from the origin on a first axis and has a voltage level of H; a second H vector, which is a voltage vector extending from the origin on a second axis that forms an electrical angle of 60 degrees with the first axis and has a voltage level of H; an M vector, which is a voltage vector extending from the origin to a midpoint between the tip of the first H vector and the tip of the second H vector and has a voltage level of M; a first L vector, which is a voltage vector extending from the origin to a midpoint between the tip of the first H vector and the origin and has a voltage level of L; and a second L vector, which is a voltage vector extending from the origin to a midpoint between the tip of the second H vector and the origin and has a voltage level of L.

[0010] The setting unit includes at least three of the first H vector, the second H vector, the M vector, the first L vector, and the second L vector in the switching pattern for each specified period.

[0011] This makes it possible to shorten the period of the zero voltage vector in the specified period, and reduce the current ripple flowing through the capacitor.

[0012] The above and other objects, features, and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which Fig. 1 is an overall configuration diagram of a control system according to one embodiment, Fig. 2 is a functional block diagram of control processing executed by a control device, Fig. 3 is a diagram showing a control mode of Y drive control, Fig. 4 is a diagram showing a control mode of H drive control, Fig. 5 is a diagram showing voltage vectors that can be output by a first inverter, Fig. 6 is a diagram showing voltage vectors that can be output by a second inverter, Fig. 7 is a diagram showing a composite vector that can be output by the first and second inverters, Fig. 8 is a diagram showing each vector in the first sector, Fig. 9 is a time chart showing an example of a setting mode of a switching pattern, and Fig. 10 is a timing chart showing a setting mode of a switching pattern according to a comparative example. 11 is a flowchart of H drive control processing executed by the control device. FIG. 12 is a time chart showing an example of a setting mode of a switching pattern according to another embodiment. FIG. 13 is a time chart showing an example of a setting mode of a switching pattern according to another embodiment. FIG. 14 is a time chart showing an example of a setting mode of a switching pattern according to another embodiment. FIG. 15 is a time chart showing an example of a setting mode of a switching pattern according to another embodiment. FIG. 16 is a time chart showing an example of a setting mode of a switching pattern according to another embodiment.

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

[0014] As shown in Fig. 1, the control system 100 includes a battery 10, which is a DC power supply, a first inverter 20, a second inverter 30, and a rotating electrical machine 40. The battery 10 is, for example, a battery pack including a series connection of unit cells. The unit cell is a single battery cell or a series connection of multiple battery cells. The battery cell is, for example, a secondary battery such as a lithium-ion battery.

[0015] The first inverter 20 and the second inverter 30 are power conversion circuits that convert DC power supplied from the battery 10 into three-phase AC power and supply it to the rotating electric machine 40 .

[0016] The first inverter 20 includes a series connection of U-, V-, and W-phase first upper arm switches SUHa, SVHa, and SWHa and U-, V-, and W-phase first lower arm switches SULa, SVLa, and SWLa. The second inverter 30 includes a series connection of U-, V-, and W-phase second upper arm switches SUHb, SVHb, and SWHb and U-, V-, and W-phase second lower arm switches SULb, SVLb, and SWLb.

[0017] In this embodiment, each of the switches SUHa to SWLa and SUHb to SWLb is a voltage-controlled semiconductor switching element, more specifically, an IGBT. In this case, the high-potential terminal of each of the switches SUHa to SWLa and SUHb to SWLb is the collector, and the low-potential terminal is the emitter. A freewheel diode is connected in anti-parallel to each of the switches SUHa to SWLb. Specifically, U-, V-, and W-phase first upper-arm diodes DUHa, DVHa, and DWHa are connected in anti-parallel to the U-, V-, and W-phase first upper-arm switches SUHa, SVHa, and SWHa, respectively, and U-, V-, and W-phase first lower-arm diodes DULa, DVLa, and DWLa are connected in anti-parallel to the U-, V-, and W-phase first lower-arm switches SULa, SVLa, and SWLa, respectively. U, V, W-phase second upper-arm diodes DUHb, DVHb, DWHb are connected in anti-parallel to the U, V, W-phase second upper-arm switches SUHb, SVHb, SWHb, and U, V, W-phase second lower-arm diodes DULb, DVLb, DWLb are connected in anti-parallel to the U, V, W-phase second lower-arm switches SULb, SVLb, SWLb.

[0018] The collectors of the first upper arm switches SUHa, SVHa, SWHa for each phase and the collectors of the second upper arm switches SUHb, SVHb, SWHb for each phase are connected via a positive bus 11, which is an electrical path such as a bus bar. The emitters of the first lower arm switches SULa, SVLa, SWLa for each phase and the emitters of the second lower arm switches SULb, SVLb, SWLb for each phase are connected via a negative bus 12, which is an electrical path such as a bus bar. The emitters of the second lower arm switches SULb, SVLb, SWLb for each phase are connected to the negative bus 12.

[0019] The control system 100 includes a power switch 14. The power switch 14 is, for example, a semiconductor switching element or a mechanical relay. The power switch 14 connects the positive bus 11 and the positive terminal of the battery 10. When the power switch 14 is turned on, the positive terminal of the battery 10 is electrically connected to the collectors of the first upper arm switches SUHa, SVHa, and SWHa of each phase. When the power switch 14 is turned off, the positive terminal of the battery 10 is electrically disconnected from the collectors of the first upper arm switches SUHa, SVHa, and SWHa of each phase.

[0020] The control system 100 includes a capacitor 15. The capacitor 15 functions as a smoothing capacitor. The capacitor 15 is connected in parallel to the series-connected body of the first upper arm switches SUHa to SWHa of each phase and the first lower arm switches SULa to SWLa of each phase.

[0021] The rotating electric machine 40 is an on-board main engine that serves as a power source for running the vehicle. The rotating electric machine 40 includes a rotor 41 and a stator 50. The rotor 41 is capable of transmitting power to the drive wheels of the vehicle. In this embodiment, the rotating electric machine 40 is a permanent magnet field type synchronous machine. The rotor 41 includes permanent magnets 42 (e.g., neodymium magnets) as field poles.

[0022] The stator 50 includes a U-phase winding 51U, a V-phase winding 51V, and a W-phase winding 51W as armature windings. The phase windings 51U, 51V, and 51W are arranged at intervals of 120 electrical degrees on the stator core that constitutes the stator 50. The phase windings 51U, 51V, and 51W are open windings.

[0023] In each phase, the emitters of first upper switches SUHa, SVHa, SWHa and the collectors of first lower switches SULa, SVLa, SWLa are connected to first ends 51Ua, 51Va, 51Wa of the windings 51U, 51V, 51W, respectively. In each phase, the emitters of second upper switches SUHb, SVHb, SWHb and the collectors of second lower switches SULb, SVLb, SWLb are connected to second ends 51Ub, 51Vb, 51Wb of the windings 51U, 51V, 51W, respectively.

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

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

[0026] Returning to the explanation of FIG. 1, the control system 100 includes a current sensor 60 , a rotation angle sensor 61 , and a voltage sensor 62 .

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

[0028] The rotation angle sensor 61 is, for example, a resolver, and detects the electrical angle of the rotor 41. The voltage sensor 62 detects the voltage between the terminals of the capacitor 15.

[0029] The detection values ​​of the sensors 60 to 62 are input to a control device 70 included in the control system 100. The control device 70 is an electronic control unit (ECU) that performs various controls of the control system 100, and includes a processor 71 and a storage unit 72 as hardware. In the control system 100, each on-board device can be controlled by an ECU corresponding to that device. However, for convenience, multiple ECUs are shown as a single control device 70 in FIG. 1.

[0030] The memory unit 72 includes a memory and a storage as hardware. The memory is a storage device for storing data used in the processing of the control device 70. The memory provides the processor 71 with a working area for temporary use when the processor 71 performs processing, for example. The memory includes, for example, a ROM or a RAM. The storage is a storage device for storing various programs and data to be read and executed by the processor 71, and is a non-transitory tangible storage medium. The storage includes, for example, an HDD or a flash memory. The storage stores program information and the like for the processing shown in FIGS. 2 and 11, which will be described later.

[0031] For example, program information stored on a non-transient physical recording medium is installed in the storage unit 72. The recording medium is, for example, a USB memory, a CD-ROM, or a DVD. Also, for example, program information transmitted via a communication network, such as over the air (OTA), is installed in the storage unit 72.

[0032] In order to control the control variable of the rotary electric machine 40 to the command value, the control device 70 controls the changeover switch 13, the switches SUHa to SWLa of the first inverter 20, and the switches SUHb to SWLb of the second inverter 30 to turn on or off while the power switch 14 is on. In this embodiment, the control variable is torque.

[0033] FIG. 2 is a block diagram showing the control process of the rotating electrical machine 40 executed by the control device 70. As shown in FIG.

[0034] The command value calculation unit 80 calculates the d-axis current command value Id* and the q-axis current command value Iq* in the dq coordinate system, which is a two-phase rotating coordinate system, based on the command torque Trq* received from a control device higher than the control device 70.

[0035] The two-phase conversion unit 81 calculates the d-axis current value Idr and the q-axis current value Iqr based on the phase currents Iur, Ivr, and Iwr detected by the current sensor 60 and the electrical angle θr detected by the rotation angle sensor 61.

[0036] The current feedback unit 82 calculates a d-axis voltage command value Vd* and a q-axis voltage command value Vq* based on the d- and q-axis current command values ​​Id* and Iq* and the d- and q-axis current values ​​Idr and Iqr. Specifically, the current feedback unit 82 calculates a d-axis current deviation, which is the difference between the d-axis current command value Id* and the d-axis current value Idr, and calculates a d-axis voltage command value Vd* as a manipulated variable for feedback-controlling the calculated d-axis current deviation to zero. The current feedback unit 82 calculates a q-axis current deviation, which is the difference between the q-axis current command value Iq* and the q-axis current value Iqr, and calculates a q-axis voltage command value Vq* as a manipulated variable for feedback-controlling the calculated q-axis current deviation to zero. The feedback control is, for example, proportional-plus-integral control.

[0037] The fixed coordinate conversion unit 83 converts the d, q-axis voltage command values ​​Vd*, Vq* in the dq coordinate system into α, β-axis command voltages Vα, Vβ in the two-phase fixed coordinate system based on the d, q-axis voltage command values ​​Vd*, Vq* and the electrical angle θr.

[0038] The setting unit 84 calculates a command voltage vector Vαβ determined by the converted α- and β-axis command voltages Vα and Vβ. The command voltage vector Vαβ is a voltage vector for controlling the torque of the rotary electric machine 40 to the command torque Trq*. Based on the calculated command voltage vector Vαβ, the setting unit 84 generates drive signals for the switches SUHa to SWLa and SUHb to SWLb of the first and second inverters 20 and 30. The drive signals include on and off commands for the switches.

[0039] Based on the generated drive signal, the switch control unit 85 controls the charge / discharge current of the gates of the switches SUHa to SWLa and SUHb to SWLb of the first and second inverters 20 and 30. As a result, the on / off of the switches SUHa to SWLa and SUHb to SWLb of the first and second inverters 20 and 30 is controlled in accordance with the drive signal.

[0040] The speed calculation unit 86 calculates the rotation speed Nr of the rotor 41 based on the electrical angle θr.

[0041] The selector 87 determines whether the drive state of the control system 100 should be Y drive control or H drive control. In the present embodiment, the selector 87 selects whether Y drive control or H drive control should be used based on the operating point of the rotating electric machine 40, which is determined by the calculated rotation speed Nr and command torque Trq*, and on the control map information. The control map information is information that defines the Y drive control region and the H drive control region in association with the rotation speed Nr and the command torque Trq*. The control map information is stored in the storage unit 72.

[0042] When Y drive control is selected by the selector 87, the setting unit 84 performs Y drive control by turning off the changeover switch 13 and PWM-driving the switches SUHa to SWLa of the first inverter 20, as shown in Fig. 3. In addition, the setting unit 84 fixes the upper arm switches SUHb, SVHb, and SWHb of the second inverter 30 to on, and fixes the lower arm switches SULb, SVLb, and SWLb of the second inverter 30 to off. As a result, the phase windings 51U, 51V, and 51W are star-connected via the second inverter 30.

[0043] On the other hand, when the H drive control is selected by the selection unit 87, the setting unit 84 performs H drive control by turning on the changeover switch 13 as shown in FIG. 4, PWM driving each of the switches SUHa to SWLa of the first inverter 20, and PWM driving each of the switches SUHb to SWLb of the second inverter 30.

[0044] Fig. 5 shows voltage vectors that can be output by the first inverter 20 in a two-phase fixed coordinate system (αβ coordinate system). Fig. 6 shows voltage vectors that can be output by the second inverter 30 in the αβ coordinate system.

[0045] In FIG. 5 , voltage vectors that the first inverter 20 can output are indicated by V1 to V8. The numbers "1, 0" written alongside the voltage vectors indicate the switching states of the first inverter 20. Specifically, "1" indicates that the upper arm switch is on and the lower arm switch is off, and "0" indicates that the upper arm switch is off and the lower arm switch is on. The numbers written alongside the voltage vectors indicate the switching states of the U, V, and W phases, from left to right. For example, "1, 0, 0" indicates that the U-phase upper arm switch and the V- and W-phase lower arm switches are on, and the U-phase lower arm switch and the V- and W-phase upper arm switches are off.

[0046] 6, V1d to V8d indicate voltage vectors that can be output by the second inverter 30. The meanings of the numbers “1, 0” and the like written alongside the voltage vectors are the same as those in the case of the first inverter 20.

[0047] 5 and 6, V1 to V6 and V1d to V6d are effective voltage vectors, and V7, V8, V7d, and V8d are zero-voltage vectors, also called reactive voltage vectors.

[0048] 7 shows the resultant vectors of the voltage vectors of the first and second inverters 20, 30 that can be realized as space vectors in the αβ coordinate system in H drive control. There are 64 possible resultant vectors.

[0049] For example, "1 / 4" indicates that the voltage vector of the first inverter 20 is V1 and the voltage vector of the second inverter 30 is V4d. Also, for example, "5 / 7" indicates that the voltage vector of the first inverter 20 is V5 and the voltage vector of the second inverter 30 is V7d.

[0050] The setting unit 84 identifies the sector in which the calculated tip of the command voltage vector Vαβ is located. The sectors divide the vector space in which the command voltage vector Vαβ can exist into six sectors based on the deflection angle of the command voltage vector Vαβ. The deflection angle of the command voltage vector Vαβ is the angle between the command voltage vector Vαβ and the α-axis (U-phase axis), and is specifically the electrical angle θr. The sign of the electrical angle θr is positive in the leftward (counterclockwise) direction. FIG. 7 shows first to sixth sectors S1 to S6 that divide the vector space into six sectors. Each sector is a region sandwiched between two axes that form an electrical angle of 60 degrees. The following description will be given using the example in which the identified sector is the first sector S1.

[0051] 8 shows the first sector. A1 is a first axis extending from the origin O, and A2 is a second axis extending from the origin O. The second axis A2 is an axis rotated 60 degrees counterclockwise with respect to the first axis A1, with the origin O as its center.

[0052] VaH is a voltage vector extending from the origin O on the first axis A1 and is a first H vector having an H voltage level. VbH is a voltage vector extending from the origin O on the second axis A2 and is a second H vector having an H voltage level.

[0053] VaL is a voltage vector extending from the origin O to the first center point P1, and is a first L vector with a voltage level of L. The first center point P1 is a point on the first axis A1, and is the midpoint between the tip of the first H vector VaH and the origin O.

[0054] VbL is a voltage vector extending from the origin O to the second center point P2, and is a second L vector with a voltage level of L. The second center point P2 is a point on the second axis A2, and is the midpoint between the tip of the second H vector VbH and the origin O.

[0055] VM is a voltage vector extending from the origin O to the third center point P3, and is an M vector with a voltage level M. The third center point P3 is the midpoint between the tip of the first H vector VaH and the tip of the second H vector VbH.

[0056] The voltage level of each vector VaH, VbH, VaL, VbL, and VM indicates the magnitude of the voltage vector. The voltage level (H level) of the first H vector VaH and the second H vector VbH is greater than the voltage level (M level) of the M vector. The voltage level of the M vector is greater than the voltage level (L level) of the first L vector VaL and the second L vector VbL.

[0057] The relationship shown in FIG. 8 also applies to the second to sixth sectors S2 to S6.

[0058] The setting unit 84 uses space vector modulation (SVM) based on the identified sector, command voltage vector Vαβ, and electrical angle θr to set a switching pattern that reduces the current ripple flowing through the capacitor 15. More specifically, the setting unit 84 includes a zero voltage vector, a first H vector VaH, a second H vector VbH, an M vector VM, a first L vector VaL, and a second L vector VbL in the switching pattern for each specified period (Tsw / 2). The specified period is a period corresponding to ½ of one switching period Tsw of the switch.

[0059] FIG. 9 shows an example of a switching pattern when the first sector is identified. In FIG. 9, (a) shows the transition of the composite vector constituting the switching pattern. (b), (c), and (d) show the transitions of voltages Vu1, Vv1, and Vw1 output from the first inverter 20 to the U-, V-, and W-phase windings 51U, 51V, and 51W. (e), (f), and (g) show the transitions of voltages Vu2, Vv2, and Vw2 output from the second inverter 30 to the U-, V-, and W-phase windings 51U, 51V, and 51W. (h) shows the transition of the inverter current Iinv (see FIG. 1) flowing into the first inverter 20.

[0060] In the example shown in Fig. 9, the setting unit 84 sets a switching pattern in which the first zero voltage vector V01, the first L vector VaL, the first H vector VaH, the M vector VM, the second H vector VbH, the second L vector VbL, and the second zero voltage vector V02 appear sequentially in a first specified period. In Fig. 9, the first zero voltage vector V01 is "7 / 8", the first L vector VaL is "7 / 4", and the first H vector VaH is "1 / 4". The M vector VM is "2 / 4". The second H vector VbH is "2 / 5", the second L vector VbL is "2 / 7", and the second zero voltage vector V02 is "8 / 7".

[0061] The setting unit 84 sets a switching pattern that is symmetrical with respect to the reference line BL as the switching pattern for the second specified period following the first specified period. The reference line BL is a line that divides one switching period Tsw into two equal parts, and is a line that separates the first specified period from the second specified period.

[0062] The dashed-dotted line in FIG. 9(h) indicates the time average value of the inverter current Iinv in a specified period (hereinafter referred to as the average current value Iave). During the periods of the zero voltage vectors V01 and V02, the inverter current Iinv becomes zero, and the deviation from the average current value Iave becomes large. Here, the above-mentioned switching pattern includes five effective voltage vectors. This shortens the period of the zero voltage vectors during which the inverter current Iinv becomes zero. As a result, the current ripple flowing through the capacitor 15 can be reduced.

[0063] The order of the voltage vectors constituting the above-described switching pattern is set under the condition that only one of the switches SUHa to SWLa and SUHb to SWLb included in the first and second inverters 20 and 30 is switched, thereby reducing the switching loss of the first and second inverters 20 and 30 and shortening the zero voltage vector period.

[0064] The above-described switching pattern includes two active voltage vectors VaL and VaH on the same first axis A1. This reduces the amount of change in the inverter current Iinv when the voltage vector is switched from V01 to VaL to VaH. The above-described switching pattern also includes two active voltage vectors VbHL and VbL on the same second axis A2. This reduces the amount of change in the inverter current Iinv when the voltage vector is switched from VbH to VbL to V02. As a result, the current ripple flowing through the capacitor 15 can be reduced.

[0065] A method for setting a switching pattern according to a comparative example is shown in Fig. 10. Figs. 10(a) to (h) correspond to Figs. 9(a) to (h) above.

[0066] In the comparative example, the switching pattern of the specified cycle includes only two effective voltage vectors, "1 / 3" and "2 / 4." This results in a longer period of zero voltage vectors in the specified cycle, and a larger deviation between the inverter current Iinv and the average current value Iave during the period when each voltage vector is selected. As a result, the current ripple flowing through the capacitor 15 increases.

[0067] Fig. 11 shows a flowchart of the H drive control process executed by the control device 70. The process shown in Fig. 11 is repeatedly executed by the processor 71 of the control device 70, for example, at a predetermined control cycle.

[0068] In step S10, the command value calculation unit 80 calculates the d-axis and q-axis current command values ​​Id* and Iq*.

[0069] In step S11, the current feedback section 82 calculates the d-axis and q-axis voltage command values ​​Vd* and Vq* based on the d-axis and q-axis current command values ​​Id* and Iq* and the d-axis and q-axis current values ​​Idr and Iqr.

[0070] In step S12, the fixed coordinate conversion unit 83 calculates α- and β-axis command voltages Vα and Vβ based on the d- and q-axis voltage command values ​​Vd* and Vq* and the electrical angle θr.

[0071] In step S13, the setting unit 84 calculates a command voltage vector Vαβ based on the α- and β-axis command voltages Vα and Vβ. In step S14, the setting unit 84 identifies which of the first to sixth sectors S1 to S6 the tip of the command voltage vector Vαβ is located in.

[0072] In step S15, a switching pattern for a specified period or one switching period Tsw is set based on the identified sector, command voltage vector Vαβ, and electrical angle θr.

[0073] In step S16, the setting unit 84 generates drive signals for the switches SUHa to SWLa and SUHb to SWLb of the first and second inverters 20 and 30 based on the set switching pattern.

[0074] According to the present embodiment described above, when the H drive control is executed, the current ripple flowing through the capacitor 15 can be reduced.

[0075] Other Embodiments The above embodiment may be modified as follows.

[0076] The method for setting the switching pattern is not limited to the example shown in FIG. 9, but may be any of the following (A) to (E).

[0077] (A) The setting unit 84 may set a switching pattern that excludes the first L vector VaL ("7 / 4") from the switching patterns shown in FIG. 9 (see FIG. 12). In this case, the effective voltage vectors included in the switching pattern of the specified period are the first H vector VaH, the M vector VM, the second H vector VbH, and the second L vector VbL. For example, when the setting unit 84 determines that the magnitude of the command voltage vector Vαβ is equal to or greater than a predetermined value (i.e., the modulation rate is equal to or greater than a predetermined modulation rate), the setting unit 84 may set a switching pattern that does not use the first L vector VaL.

[0078] (B) The setting unit 84 may include the second L vector VbL (2 / 8) in the switching pattern shown in Fig. 12 instead of the M vector VM (2 / 4) (see Fig. 13). In the example shown in Fig. 13, the number of times the switching state of the U phase in the second inverter 30 is switched is increased.

[0079] (C) In the switching pattern shown in FIG. 9, the setting unit 84 may reverse the order of the first L vector VaL and the first H vector VaH as shown in FIG.

[0080] (D) The setting unit 84 may set a switching pattern excluding the M vector ("2 / 4") from the switching patterns shown in Fig. 14 (see Fig. 15). Note that, for example, when the setting unit 84 determines that the magnitude of the command voltage vector Vαβ is less than a predetermined value (i.e., the modulation rate is less than a predetermined modulation rate), the setting unit 84 may set the switching pattern shown in Fig. 15.

[0081] (E) The setting unit 84 may set a switching pattern excluding the first L vector VaL ("7 / 4") and the second L vector ("2 / 7") from the switching patterns shown in Fig. 14 (see Fig. 16). For example, when the setting unit 84 determines that the magnitude of the command voltage vector Vαβ is equal to or greater than a predetermined value, the setting unit 84 may set the switching pattern shown in Fig. 16.

[0082] The control system 100 does not need to be provided with the changeover switch 13. In this case, the control system is a system that is always in the H drive state.

[0083] The DC power source is not limited to a battery, and may be, for example, a fuel cell.

[0084] The rotating electric machine is not limited to a permanent magnet field type synchronous machine, and may be, for example, an induction machine.

[0085] The rotating electric machine is not limited to a three-phase one, but may be a two-phase one or a four-phase or more phase one.

[0086] The semiconductor switches constituting the first inverter and the second inverter are not limited to IGBTs, but may be, for example, N-channel MOSFETs. In this case, the high-potential terminal of the switch is the drain, and the low-potential terminal is the source. Each switch also has a body diode.

[0087] The inverter, rotating electric machine, and control device may be installed in a mobile body other than a vehicle, such as an aircraft or a ship. If the mobile body is an aircraft, the rotating electric machine serves as a power source for the aircraft's flight, and if the mobile body is a ship, the rotating electric machine serves as a power source for the ship's navigation. Furthermore, the inverter, rotating electric machine, and control device may be installed in a mobile body other than a vehicle.

[0088] The control unit and method described herein may be implemented by a special-purpose computer configured by configuring a processor and memory programmed to perform one or more functions embodied in a computer program. Alternatively, the control unit and method described herein may be implemented by a special-purpose computer configured by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the control unit and method described herein may be implemented by one or more special-purpose computers configured by combining a processor and memory programmed to perform one or more functions with a processor configured with one or more hardware logic circuits. Furthermore, the computer program may be stored in a computer-readable non-transitory tangible recording medium as instructions executed by a computer.

[0089] The following describes characteristic configurations extracted from the above-described embodiments. [Configuration 1] A rotating electric machine (40) having a multi-phase armature winding (51U to 51W); a first inverter (20) having first upper arm switches (SUHa to SWHa) and first lower arm switches (SULa to SWLa) connected in series for the number of phases, the series-connected body of the first upper arm switches and the first lower arm switches being connected in parallel to a DC power source (10); a second inverter (30) having second upper arm switches (SUHb to SWHb) and second lower arm switches (SULb to SWLb) connected in series for the number of phases; a positive bus (11) for each phase electrically connecting a high potential side terminal of the first upper arm switch and a high potential side terminal of the second upper arm switch; and a negative bus (12) for each phase electrically connecting a low potential side terminal of the first lower arm switch and a low potential side terminal of the second lower arm switch. a capacitor (15) connected in parallel to the series connection of the first upper arm switch and the first lower arm switch, wherein in each phase, a low potential side terminal of the first upper arm switch and a high potential side terminal of the first lower arm switch are electrically connected to a first end of the armature winding, and in each phase, a low potential side terminal of the second upper arm switch and a high potential side terminal of the second lower arm switch are electrically connected to a second end of the armature winding, a setting unit (84) that sets a switching pattern for the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch for each specified period (Tsw / 2) in H drive control that PWM drives the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch, and a switch control unit (85) that controls on or off of the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch based on the set switching pattern, and a zero voltage vector and a space vector in the H drive control.a first H vector (VaH) which is a voltage vector extending from an origin (O) on a first axis (A1) and has a voltage level of H; a second H vector (VbH) which is a voltage vector extending from the origin on a second axis (A2) which forms an electrical angle of 60 degrees with the first axis and has a voltage level of H; a first L vector (VaL) which is a voltage vector extending from the origin to a midpoint (P1) between the tip of the first H vector and the origin and has a voltage level of L; a second L vector (VbL) which is a voltage vector extending from the origin to a midpoint (P2) between the tip of the second H vector and the origin and has a voltage level of L; and an M vector (VM) which is a voltage vector extending from the origin to a midpoint (P3) between the tip of the first H vector and the tip of the second H vector and has a voltage level of M, The control device for a rotating electric machine according to Configuration 1, wherein the setting unit includes at least three of the first H vector, the second H vector, the M vector, the first L vector, and the second L vector in the switching pattern for each specified period. [Configuration 2] The control device for a rotating electric machine according to Configuration 1, wherein the setting unit includes at least four of the first H vector, the second H vector, the M vector, the first L vector, and the second L vector in the switching pattern for each specified period. [Configuration 3] The control device for a rotating electric machine according to Configuration 2, wherein the setting unit includes the first H vector, the second H vector, the M vector, the first L vector, and the second L vector in the switching pattern for each specified period. [Configuration 4] The control device for a rotating electric machine according to any one of Configurations 1 to 3, wherein the setting unit sets an order of voltage vectors constituting the switching pattern for each specified period under the condition that the switching state of only any one switch of any one phase among the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch is switched. [Configuration 5] The setting unit includes the first H vector and the first L vector in the switching pattern for each specified period,The control device for a rotating electric machine according to configuration 4, wherein the setting unit sets an order of voltage vectors that constitute the switching pattern for each specified period by imposing a condition that the first L vector and the first H vector are adjacent in time. [Configuration 6] The control device for a rotating electric machine according to configuration 4 or 5, wherein the setting unit includes the second H vector and the second L vector in the switching pattern for each specified period, and sets an order of voltage vectors that constitute the switching pattern for each specified period by imposing a condition that the second L vector and the second H vector are adjacent in time.

[0090] 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 electrical machine (40) having a multi-phase armature winding (51U to 51W), a first inverter (20) having a number of series-connected first upper arm switches (SUHa to SWHa) and first lower arm switches (SUL a 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, 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, and a capacitor (15) connected in parallel to the series connection of the first upper arm switches and the first lower arm switches, in a control device (70) for a rotating electrical machine applied to a system comprising: in each phase, the low-potential side terminal of the first upper arm switch and the high-potential side terminal of the first lower arm switch are electrically connected to the first end of the armature winding; in each phase, the low-potential side terminal of the second upper arm switch and the high-potential side terminal of the second lower arm switch are electrically connected to the second end of the armature winding; in H drive control for PWM driving the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch, a setting unit (84) for setting a switching pattern for each specified period (Tsw / 2) of the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch, and a switch control unit (85) for controlling the on or off of the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch based on the set switching pattern; as space vectors in the H drive control, a zero voltage vector, and a first H vector (VaH) which is a voltage vector extending from the origin (O) on the first axis (A1) and having a voltage level of H level.A voltage vector extending from the origin on a second axis (A2) that forms an electrical angle of 60 degrees with the first axis, the second H vector (VbH) having a voltage level of H level; A voltage vector extending from the origin to the central point (P1) between the tip of the first H vector and the origin, the first L vector (VaL) having a voltage level of L level; A voltage vector extending from the origin to the central point (P2) between the tip of the second H vector and the origin, the second L vector (VbL) having a voltage level of L level; A voltage vector extending from the origin to the central point (P3) between the tip of the first H vector and the tip of the second H vector, the M vector (VM) having a voltage level of M level; are defined, The setting unit includes at least three of the first H vector, the second H vector, the M vector, the first L vector, and the second L vector in the switching pattern for each of the specified periods, a control device for a rotating electrical machine.

2. The setting unit includes at least four of the first H vector, the second H vector, the M vector, the first L vector, and the second L vector in the switching pattern for each of the specified periods, in the control device for a rotating electrical machine according to claim 1.

3. The setting unit includes the first H vector, the second H vector, the M vector, the first L vector, and the second L vector in the switching pattern for each of the specified periods, in the control device for a rotating electrical machine according to claim 2.

4. The setting unit sets the order of voltage vectors constituting the switching pattern for each of the specified periods, by imposing a condition that only the switching state of any one switch of any one phase among the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch is switched, in the control device for a rotating electrical machine according to any one of claims 1 to 3.

5. The setting unit includes the first H vector and the first L vector in the switching pattern for each of the specified periods, and sets the order of voltage vectors constituting the switching pattern for each of the specified periods, by imposing a condition that the first L vector and the first H vector are temporally adjacent to each other, in the control device for a rotating electrical machine according to claim 4.

6. The setting unit includes the second H vector and the second L vector in the switching pattern for each of the specified periods, and sets the order of voltage vectors constituting the switching pattern for each of the specified periods, by imposing a condition that the second L vector and the second H vector are temporally adjacent to each other, in the control device for a rotating electrical machine according to claim 4.

7. A rotating electrical machine (40) having a multi-phase armature winding (51U to 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, wherein the series connection of the first upper arm switches and the first lower arm switches is 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, 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, and a capacitor (15) connected in parallel to the series connection of the first upper arm switches and the first lower arm switches. In a program applied to the system, in each phase, the low-potential side terminal of the first upper arm switch and the high-potential side terminal of the first lower arm switch are electrically connected to the first end of the armature winding, in each phase, the low-potential side terminal of the second upper arm switch and the high-potential side terminal of the second lower arm switch are electrically connected to the second end of the armature winding, and the processor (71) is caused to execute a setting process for setting a switching pattern for each specified period of the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch in H drive control for PWM driving the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch, and a process for controlling the on or off of the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch based on the set switching pattern. As the space vector in the H drive control, a zero voltage vector, a first H vector (VaH) which is a voltage vector extending from the origin (O) on the first axis (A1) and having a voltage level of H level,A voltage vector extending from the origin on a second axis (A2) that forms an electrical angle of 60 degrees with the first axis, the second H vector (VbH) having a voltage level of H level; A first L vector (VaL) that is a voltage vector extending from the origin to a central point (P1) between the tip of the first H vector and the origin and having a voltage level of L level; A second L vector (VbL) that is a voltage vector extending from the origin to a central point (P2) between the tip of the second H vector and the origin and having a voltage level of L level; An M vector (VM) that is a voltage vector extending from the origin to a central point (P3) between the tip of the first H vector and the tip of the second H vector and having a voltage level of M level are defined, and in the setting process, at least three of the first H vector, the second H vector, the M vector, the first L vector, and the second L vector are included in the switching pattern for each of the specified periods. Program.

8. A rotating electrical machine (40) having a multi-phase armature winding (51U to 51W), a first inverter (20) having a number of series-connected first upper arm switches (SUHa to SWHa) and first lower arm switches (SUL a to SWL a) corresponding to the number of phases, with 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 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, 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, and a capacitor (15) connected in parallel to the series connection of the first upper arm switch and the first lower arm switch, in a control method for a rotating electrical machine applied to a system comprising: in each phase, the low-potential side terminal of the first upper arm switch and the high-potential side terminal of the first lower arm switch are electrically connected to the first end of the armature winding; in each phase, the low-potential side terminal of the second upper arm switch and the high-potential side terminal of the second lower arm switch are electrically connected to the second end of the armature winding; in H drive control for PWM driving the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch, a setting step of setting a switching pattern for each specified period of the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch; and a step of controlling the on or off of the first upper arm switch, the first lower arm switch, the second upper arm switch, and the second lower arm switch based on the set switching pattern, and as a space vector in the H drive control, a zero voltage vector, a voltage vector extending from the origin (O) on the first axis (A1), and a first H vector (VaH) having a voltage level of H level.A voltage vector extending from the origin on a second axis (A2) that forms an electrical angle of 60 degrees with the first axis, the second H vector (VbH) having a voltage level of H level; A first L vector (VaL) that is a voltage vector extending from the origin to a central point (P1) between the tip of the first H vector and the origin and having a voltage level of L level; A second L vector (VbL) that is a voltage vector extending from the origin to a central point (P2) between the tip of the second H vector and the origin and having a voltage level of L level; An M vector (VM) that is a voltage vector extending from the origin to a central point (P3) between the tip of the first H vector and the tip of the second H vector and having a voltage level of M level are defined, and in the setting step, at least three of the first H vector, the second H vector, the M vector, the first L vector, and the second L vector are included in the switching pattern for each of the specified periods. A method for controlling a rotating electrical machine.

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