Control device for rotary electric machine, and program

Abstract

To provide a control device for a rotary electric machine capable of reducing a torque ripple of generation torque of the rotary electric machine, and a program.SOLUTION: A control device 30 calculates a composite current by superposing a higher harmonic current for inducing a magnetic field current in magnetic field coils of a rotor of a rotary electric machine 40 on a fundamental wave current to flow to stator coils 52U-52W of the rotary electric machine 40 and performs switching control of an inverter 20 to make the calculated composite current flow to the stator coils 52U-52W. The control device 30 calculates the composite current under the condition that a frequency of an envelope of the higher harmonic current is equal to a frequency of the fundamental wave current and the condition that a phase difference between the envelope and the fundamental wave current is made into a predetermined phase difference, and the predetermined phase difference is set to a phase difference for which e.g., an electric angle is 50° or more and 90° or less.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a control device and a program for a rotating electric machine. [Background technology]

[0002] Conventionally, a system is known that includes a rotating electric machine having a stator including a stator winding and a rotor including a field winding, and an inverter electrically connected to the stator winding. The rotor has a rotor core and main pole parts that are provided at a predetermined interval in the circumferential direction and protrude radially from the rotor core. The field winding has a first winding part and a second winding part electrically connected in series, and the first winding part and the second winding part are wound around each main pole part. The rotor has a diode electrically connected in parallel to the series connection of the first winding part and the second winding part, and a capacitor electrically connected in parallel to the second winding part. An example of such a system is described in, for example, Patent Document 1.

[0003] The system includes a control device that controls the switching of the inverter so that a harmonic current for inducing a field current in the field winding is superimposed on a fundamental current flowing through the stator winding. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2020-191743 A Summary of the Invention [Problem to be solved by the invention]

[0005] The induced field current contains a ripple component. This ripple component causes torque ripple in the torque generated by the rotating electric machine. A new configuration that can reduce this torque ripple is desired.

[0006] A primary object of the present disclosure is to provide a control device and program for a rotating electric machine that can reduce torque ripple in the torque generated by the rotating electric machine. [Means for solving the problem]

[0007] The present disclosure provides a rotating electric machine having a stator including a stator winding and a rotor including a field winding, an inverter electrically connected to the stator winding; A control device for a rotating electric machine applied to a system including: The rotor has a rotor core and main poles that are provided at predetermined intervals in a circumferential direction and protrude radially from the rotor core, the field winding has a first winding portion and a second winding portion electrically connected in series, The first winding portion and the second winding portion are wound around the respective main pole portions, The rotor is a diode electrically connected in parallel to the series connection of the first winding portion and the second winding portion; a capacitor electrically connected in parallel to either the first winding portion or the second winding portion; having a composite current calculation unit that calculates a composite current obtained by superimposing a harmonic current for inducing a field current in the field winding on a fundamental current to be passed through the stator winding; a switch control unit that performs switching control of the inverter so as to pass the calculated combined current through the stator winding; Equipped with The composite current calculation unit calculating the composite current under the condition that the frequency of the envelope of the harmonic current is equal to the frequency of the fundamental current and that the phase difference (θh) between the envelope and the fundamental current is a predetermined phase difference; The predetermined phase difference is set to a phase difference equal to or greater than "50°+180°×N" and equal to or less than "90°+180°×N" (N=0, 1, -1, -2) in electrical angle.

[0008] In the present disclosure, the composite current calculation unit calculates a composite current in which the harmonic current is superimposed on the fundamental current, under the condition that the frequency of the envelope of the harmonic current is equal to the frequency of the fundamental current.

[0009] When the phase difference between the envelope and the fundamental current changes, the torque ripple of the torque generated by the rotating electric machine changes. When N is 0, 1, -1, or -2, the torque ripple can be reduced by setting the phase difference between the envelope and the fundamental current to a predetermined phase difference that is equal to or greater than "50°+180°×N" and equal to or less than "90°+180°×N" in electrical angle.

[0010] In view of this, the composite current calculation unit calculates the composite current by further imposing a condition that the phase difference between the envelope of the harmonic current and the fundamental current is the above-mentioned predetermined phase difference. This makes it possible to reduce the torque ripple of the torque generated by the rotating electric machine. In addition, a simple parameter such as the above-mentioned phase difference can be used as a parameter for reducing the torque ripple. [Brief description of the drawings]

[0011] [Figure 1] 1 is an overall configuration diagram of a control system for a rotating electric machine according to a first embodiment; [Diagram 2] FIG. 2 is a diagram showing an inverter and its peripheral configuration. [Diagram 3] FIG. [Figure 4] FIG. 4 is a diagram showing an electric circuit provided in the rotor. [Diagram 5] FIG. 4 is a block diagram of a torque control process of the control device. [Figure 6] FIG. 4 is a diagram showing a fundamental current, a harmonic current, and a harmonic phase difference. [Figure 7] Calculation results showing the relationship between harmonic phase difference, generated torque, and torque ripple rate at 1500 rpm. [Figure 8] 4 is a time chart showing changes in generated torque at 1500 rpm. [Figure 9] 4 is a time chart showing changes in generated torque at 1500 rpm. [Figure 10] Calculation results showing the relationship between harmonic phase difference, generated torque, and torque ripple rate at 3000 rpm. [Figure 11] 4 is a time chart showing changes in torque generated at 3000 rpm. [Figure 12] 4 is a time chart showing changes in torque generated at 3000 rpm. [Figure 13] FIG. 2 is a diagram showing a schematic diagram of the flow of magnetic flux. [Figure 14] FIG. 2 is a diagram showing a schematic diagram of the flow of magnetic flux. [Figure 15] FIG. 4 is a diagram showing a schematic diagram of the flow of magnetic flux and the state of forces. [Figure 16] FIG. 4 is a diagram illustrating a schematic diagram of a magnetic flux flow corresponding to a harmonic phase difference. [Figure 17] 5 is a flowchart showing a procedure of a torque control process. [Figure 18] FIG. 11 is a cross-sectional view of a rotor and a stator according to a second embodiment. [Figure 19] FIG. 4 is a diagram showing a notch at the tip of the main pole. [Figure 20] FIG. [Figure 21] Calculation results showing the relationship between harmonic phase difference, generated torque, and torque ripple rate at 500 rpm and when there is no notch. [Figure 22] 4 is a time chart showing changes in generated torque at 500 rpm and when there is no notch. [Diagram 23] 4 is a time chart showing changes in generated torque, etc., when the rpm is 500, there is no notch, and the harmonic phase difference is 110°. [Figure 24] 4 is a time chart showing changes in generated torque, etc., when the rpm is 500, there is no notch, and the harmonic phase difference is 70°. [Diagram 25] Calculation results showing the relationship between harmonic phase difference, generated torque, and torque ripple rate at 500 rpm and with a notch. [Figure 26] 4 is a time chart showing changes in generated torque at 500 rpm and when a notch is present. [Figure 27]4 is a time chart showing changes in generated torque, etc., when the rotation speed is 500 rpm, there is a notch, and the harmonic phase difference is 110°. [Figure 28] 4 is a time chart showing changes in generated torque, etc., when the rotation speed is 500 rpm, there is a notch, and the harmonic phase difference is 70°. [Figure 29] FIG. 11 is a diagram showing the relationship between the phase of a fundamental wave current and a reference phase according to the third embodiment. [Diagram 30] 5 is a flowchart showing a procedure of a torque control process. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Several embodiments will be described with reference to the drawings. In several embodiments, functionally and / or structurally corresponding and / or associated parts may be given the same reference numerals or reference numerals with different digits of 100 or more. For corresponding and / or associated parts, the description of other embodiments may be referred to.

[0013] First Embodiment A first embodiment of a rotating electric machine and a control device for the rotating electric machine according to the present disclosure will be described below with reference to the drawings. The rotating electric machine and the control device configure a control system for the rotating electric machine, and the control system is mounted on a vehicle. The rotating electric machine is a power source for driving the vehicle.

[0014] 1, the control system includes a DC power supply 10, an inverter 20, a control device 30, and a rotating electric machine 40. The rotating electric machine 40 is a field winding type synchronous machine. For example, the rotating electric machine 40, the inverter 20, and the control device 30 may be included to configure an electrically and mechanically integrated drive device, or the rotating electric machine 40, the inverter 20, and the control device 30 may each be configured by a respective component.

[0015] The rotating electric machine 40 includes a housing 41, and a stator 50 and a rotor 60 housed in the housing 41. The rotating electric machine 40 of this embodiment is an inner rotor type rotating electric machine in which the rotor 60 is disposed radially inside the stator 50.

[0016] The stator 50 includes a stator core 51 and a stator winding 52. The stator winding 52 is made of, for example, a copper wire, and includes U-, V-, and W-phase windings 52U, 52V, and 52W that are arranged offset from each other by 120° in electrical angle.

[0017] The rotor 60 includes a rotor core 61 and a field winding 70. The field winding 70 is formed by, for example, compression molding. This improves the space factor and improves the ease of assembly of the field winding 70. The field winding 70 may be formed of, for example, an aluminum wire. The aluminum wire has a small specific gravity and can reduce the centrifugal force when the rotor 60 rotates. The aluminum wire has a lower strength and hardness than a copper wire and is suitable for compression molding. The field winding 70 is not limited to an aluminum wire, and may be, for example, a copper wire or CNT (carbon nanotube). The field winding 70 does not have to be formed by compression molding.

[0018] The rotating shaft 32 is inserted through a central hole of the rotor core 61. The rotating shaft 32 is rotatably supported by the housing 41 via a bearing .

[0019] As shown in FIG. 2, the inverter 20 includes a series connection of U-, V-, and W-phase upper-arm switches SUp, SVp, and SWp and U-, V-, and W-phase lower-arm switches SUn, SVn, and SWn. First ends of the U-, V-, and W-phase windings 52U, 52V, and 52W are connected to the connection points of the U-, V-, and W-phase upper-arm switches SUp, SVp, and SWp and the U-, V-, and W-phase lower-arm switches SUn, SVn, and SWn. Second ends of the U-, V-, and W-phase windings 52U, 52V, and 52W are connected at the neutral point. That is, in this embodiment, the U-, V-, and W-phase windings 52U, 52V, and 52W are star-connected. In this embodiment, each of the switches SUp to SWn is an IGBT. A freewheel diode is connected in inverse parallel to each of the switches SUp to SWn.

[0020] The collectors of the U-, V-, and W-phase upper-arm switches SUp, SVp, and SWp are connected to a positive terminal of a DC power supply 10. The emitters of the U-, V-, and W-phase lower-arm switches SUn, SVn, and SWn are connected to a negative terminal of the DC power supply 10. A smoothing capacitor 11 is connected in parallel to the DC power supply 10.

[0021] Next, the stator 50 and the rotor 60 will be described with reference to FIG.

[0022] The stator 50 and the rotor 60 are both arranged coaxially (specifically, on the central axis O of rotation) with the rotating shaft 32. In the following description, the direction in which the rotating shaft 32 extends is referred to as the axial direction, the direction extending radially from the center of the rotating shaft 32 is referred to as the radial direction, and the direction extending circumferentially around the rotating shaft 32 is referred to as the circumferential direction.

[0023] The stator 50 is made of laminated steel plates made of soft magnetic material, and has an annular back yoke 51a and a plurality of teeth 51b protruding radially inward from the back yoke 51a. A plurality of slots 54 are formed between adjacent teeth 51b in the circumferential direction. The phase windings of each phase are accommodated in each slot 54 in a predetermined order to form the stator winding 52. For example, the stator 50 may have a segment coil structure using a plurality of conductor segments. However, the structure of the stator winding 52 is arbitrary.

[0024] The rotor 60 is made of a soft magnetic material, for example, laminated steel plates. The rotor 60 has a cylindrical rotor core 61 and a plurality of main poles 62 protruding radially outward from the rotor core 61. In this embodiment, eight main poles 62 are provided at equal intervals in the circumferential direction.

[0025] The field winding 70 includes a first winding portion 71a and a second winding portion 71b. In each main pole portion 62, the first winding portion 71a is wound radially outward, and the second winding portion 71b is wound radially inward from the first winding portion 71a. In each main pole portion 62, the winding directions of the first winding portion 71a and the second winding portion 71b are the same. In addition, among the main pole portions 62 adjacent in the circumferential direction, the winding directions of the winding portions 71a and 71b wound around one of the main pole portions 62 are opposite to the winding directions of the winding portions 71a and 71b wound around the other of the main pole portions 62 adjacent in the circumferential direction. Therefore, the magnetization directions of the main pole portions 62 adjacent in the circumferential direction are opposite to each other.

[0026] FIG. 4 shows an electric circuit on the rotor 60 side, which includes the windings 71a and 71b wound around a common main pole 62. The rotor 60 is provided with a diode 80 as a rectifying element and a capacitor 90. The diode 80 is electrically connected in parallel to the series connection of the first winding 71a and the second winding 71b. In detail, the cathode of the diode 80 is connected to a first end of the first winding 71a, and the second end of the first winding 71a is connected to a first end of the second winding 71b. The anode of the diode 80 is connected to a second end of the second winding 71b. The capacitor 90 is electrically connected in parallel to the second winding 71b. In FIG. 4, L1 indicates the inductance of the first winding 71a, L2 indicates the inductance of the second winding 71b, and C indicates the capacitance of the capacitor 90.

[0027] In this embodiment, a series resonant circuit is configured including the first winding portion 71a, the capacitor 90, and the diode 80, and a parallel resonant circuit is configured including the second winding portion 71b and the capacitor 90. In Fig. 4, f1 indicates a first resonant frequency which is the resonant frequency of the series resonant circuit, and f2 indicates a second resonant frequency which is the resonant frequency of the parallel resonant circuit.

[0028] Alternatively, the anode of the diode 80 may be connected to the first end of the first winding portion 71a, and the cathode of the diode 80 may be connected to the second end of the second winding portion 71b.

[0029] Returning to the explanation of FIG. 2, the control system includes a current sensor 21, an angle sensor 22, a voltage sensor 23, and an accelerator sensor 24. The current sensor 21 detects at least two phases of current among the phase currents flowing through the rotating electric machine 40. The angle sensor 22 detects the rotation angle (electrical angle) of the rotor 60. The voltage sensor 23 detects the voltage of the DC power supply 10. The accelerator sensor 24 detects the amount of operation of an accelerator operating member (specifically, an accelerator pedal) operated by the driver of the vehicle. The detection values ​​of the sensors 21 to 24 are input to the control device 30.

[0030] The control device 30 is an electronic control unit mainly composed of a microcomputer 31. The microcomputer 31 includes a CPU (Central Processing Unit). The functions provided by the microcomputer 31 can be provided by software recorded in a substantial memory device and a computer that executes the software, by software alone, by hardware alone, or by a combination of these. For example, when the microcomputer 31 is provided by an electronic circuit that is hardware, it can be provided by a digital circuit including a large number of logic circuits, or by an analog circuit. For example, the microcomputer 31 executes a program stored in a non-transitory tangible storage medium as a storage unit provided in the microcomputer 31. The program includes, for example, a program for processing shown in Figs. 5 and 17, which will be described later. A method corresponding to the program is executed by executing a set of instructions that constitute the program. The storage unit is, for example, a non-volatile memory. The program stored in the storage unit can be updated via a communication network such as the Internet, for example, OTA (Over The Air), etc.

[0031] The control device 30 generates drive signals that turn on and off each of the switches SUp to SWn that configure the inverter 20. In particular, the control device 30 generates drive signals that turn on and off each of the arm switches SUp to SWn in order to convert the DC power output from the DC power source 10 into AC power and supply it to the U-, V-, and W-phase windings 52U, 52V, and 52W, and supplies the generated drive signals to the gates of each of the arm switches SUp to SWn.

[0032] The control device 30 turns on and off each of the switches SUp to SWn so that a composite current of the fundamental current and the harmonic current flows through each of the phase windings 52U, 52V, 52W. The fundamental current is a current that mainly serves to generate torque in the rotating electric machine 40. The harmonic current is a current that mainly serves to excite the field winding 70 and induce a field current in the field winding 70. The phase currents flowing through the phase windings 52U, 52V, 52W are shifted by 120° in electrical angle.

[0033] The torque control of the rotating electrical machine 40 executed by the control device 30 will be described with reference to FIG.

[0034] The two-phase conversion unit 100 converts the U-, V-, and W-phase currents in a three-phase fixed coordinate system into a d-axis current Idr and a q-axis current Iqr in a two-phase rotating coordinate system (dq coordinate system) based on the detection value of the current sensor 21 and the electrical angle θe detected by the angle sensor 22.

[0035] The command current calculation unit 101 calculates the d-axis and q-axis command currents Id* and Iq* based on the command torque Trq*. The d-axis and q-axis command currents Id* and Iq* are values ​​reflecting the fundamental wave current and the harmonic currents exciting the field winding 70. In detail, the d-axis and q-axis command currents Id* and Iq* are sum values ​​of the d-axis and q-axis fundamental command currents of the DC components corresponding to the fundamental wave current and the d-axis and q-axis harmonic command currents of the AC components corresponding to the harmonic currents, and correspond to the "composite currents" in this embodiment. For example, the command current calculation unit 101 may calculate the d-axis and q-axis command currents Id* and Iq* based on the command torque Trq* and map information in which the command torque Trq* and the d-axis and q-axis command currents Id* and Iq* are associated with each other. Here, the command torque Trq* may be set to be larger as the accelerator operation amount detected by the accelerator sensor 24 increases. In this embodiment, the command current calculation unit 101 corresponds to a "composite current calculation unit."

[0036] The current control unit 102 calculates the d-axis current deviation ΔId by subtracting the d-axis current Idr from the d-axis command current Id*.The current control unit 102 calculates the q-axis current deviation ΔIq by subtracting the q-axis current Iqr from the q-axis command current Iq*.

[0037] The current control unit 102 calculates a d-axis command voltage Vd* based on the d-axis current deviation ΔId as a manipulated variable for feedback-controlling the d-axis current Idr to the d-axis command current Id*. The current control unit 102 calculates a q-axis command voltage Vq* based on the q-axis current deviation ΔIq as a manipulated variable for feedback-controlling the q-axis current Iqr to the q-axis command current Iq*.

[0038] A three-phase conversion unit 103 converts the d- and q-axis command voltages Vd, Vq in the two-phase rotating coordinate system into U-, V- and W-phase voltage command values ​​VU*, VV*, and VW* in the three-phase fixed coordinate system based on the d- and q-axis command voltages Vd*, Vq* and the electrical angle θe. The U-, V- and W-phase voltage command values ​​VU*, VV*, and VW* have waveforms with phases shifted by 120 degrees in electrical angle.

[0039] The frequencies of the harmonic components included in the U-, V-, and W-phase voltage command values ​​VU*, VV*, and VW* are set to a frequency close to the first resonant frequency f1 or the second resonant frequency f2. This increases the excitation and reduces the amplitude of the harmonic current, thereby reducing the torque ripple of the rotating electric machine 40.

[0040] The signal generating unit 104 generates drive signals for the upper and lower arm switches SUp to SWn of the U, V and W phases by three-phase modulation based on the U, V and W phase voltage command values ​​VU*, VV* and VW* and the voltage Vdc of the DC power supply 10 detected by the voltage sensor 23. The generated drive signals are input to the gates of the respective switches. This executes switching control of the inverter 20. In this embodiment, the signal generating unit 104 corresponds to a "switch control unit."

[0041] As a result of switching control of inverter 20, a composite current in which harmonic current (see solid line in FIG. 6(b)) is superimposed on fundamental current (see FIG. 6(a)) flows through each phase winding 52U, 52V, 52W. Here, the dashed dotted line in FIG. 6(b) indicates the envelope of the harmonic current. The envelope of the harmonic current has the same period as the fundamental current. The values ​​on the vertical axis in FIG. 6 indicate the relative relationship between the magnitudes of the waveforms shown in FIGS. 6(a) and (b).

[0042] θh shown in Fig. 6 is the phase difference between the envelope of the harmonic current and the fundamental current, and is hereinafter referred to as the harmonic phase difference. As shown in Fig. 6, there are two envelopes of the harmonic current. In this embodiment, the harmonic phase difference θh is the phase difference between the zero-up cross timing of the fundamental current and the zero-cross timing (zero-up cross timing or zero-down cross timing) of the two envelopes. In the example shown in Fig. 6, the zero-up cross timing of one of the two envelopes of the harmonic current coincides with the zero-down timing of the other envelope.

[0043] The command current calculation unit 101 of the control device 30 calculates the d-axis and q-axis command currents Id* and Iq* under the condition that the harmonic phase difference θh is a predetermined phase difference in the above torque control. In this embodiment, the predetermined phase difference is set to a phase difference of "50°+180°×N" or more and "90°+180°×N" or less (N=0, 1, -1, -2) in electrical angle. The sign of the harmonic phase difference θh is positive when the phase of the envelope of the harmonic current is advanced with respect to the fundamental current, and negative when the phase of the envelope of the harmonic current is delayed with respect to the fundamental current. In the example shown in FIG. 6, the harmonic phase difference θh is positive. The above setting of the harmonic phase difference θh is for reducing the torque ripple rate while maintaining the maximum torque generated by the rotating electric machine 40 at a high level. In this embodiment, the torque ripple rate refers to the ratio (ΔTr / Tdc) of the fluctuation amount "ΔTr" of the generated torque to the DC component Tdc of the torque generated by the rotary electric machine 40. The fluctuation amount is, for example, the difference between the maximum value and the minimum value of the generated torque in one period.

[0044] 7 shows the calculation results of the relationship between the harmonic phase difference θh and the torque generated by the rotating electric machine 40, and the calculation results of the relationship between the harmonic phase difference θh and the torque ripple rate when the rotation speed of the rotor 60 is 1500 rpm. In FIG. 7, the 18Ap line shows the calculation results when the harmonic current has a peak value of 18% of the peak value of the fundamental current, and the 22Ap line shows the calculation results when the harmonic current has a peak value of 22% of the peak value of the fundamental current. The 18Ap line was calculated when the harmonic phase difference θh was 110°, 90°, 80°, and 70°, and the 22Ap line was calculated when the harmonic phase difference θh was 70°, 60°, 50°, and 40°. The peak value of the harmonic current is increased when the harmonic phase difference θh is less than 70° in order to minimize the variation in the maximum generated torque of the rotating electrical machine 40 within the range of the harmonic phase difference θh of 40° to 110°.

[0045] Of the calculation results of the generated torque and torque ripple rate shown in Fig. 7, the calculation results corresponding to harmonic phase differences θh of 110°, 90°, 80°, and 70° were obtained from the calculation results of the transition of the generated torque shown in Fig. 8. Also, of the calculation results of the generated torque and torque ripple rate shown in Fig. 7, the calculation results corresponding to harmonic phase differences θh of 70°, 60°, 50°, and 40° were obtained from the calculation results of the transition of the generated torque shown in Fig. 9. In each graph of Figs. 8 and 9, the horizontal axis scale is the same, and the vertical axis scale is also the same.

[0046] The torque ripple rate increases as the harmonic phase difference θh becomes larger than 90° (i.e., the more the phase of the envelope of the harmonic current lags behind the fundamental current). On the other hand, the torque ripple rate decreases as the harmonic phase difference θh becomes smaller than 90° (i.e., the more the phase of the envelope of the harmonic current leads behind the fundamental current), and is minimum at around 70°. The torque ripple rate increases as the harmonic phase difference θh becomes smaller than 70°. The torque ripple rate when the harmonic phase difference θh is 50° is equivalent to the torque ripple rate when the harmonic phase difference θh is 90°.

[0047] Fig. 10 shows the calculation results of the relationship between the harmonic phase difference θh and the torque generated by the rotating electric machine 40, and the calculation results of the relationship between the harmonic phase difference θh and the torque ripple rate when the rotation speed of the rotor 60 is 3000 rpm. In Fig. 10, the setting conditions of the peak value of the harmonic current are the same as in Fig. 7. In addition, in each graph in Fig. 10, the horizontal axis scale is the same as in Fig. 7, and the vertical axis scale is also the same as in Fig. 7.

[0048] Of the calculation results of the generated torque and torque ripple rate shown in Fig. 10, the calculation results corresponding to harmonic phase differences θh of 110°, 90°, 80°, and 70° were obtained from the calculation results of the transition of the generated torque shown in Fig. 11. Also, of the calculation results of the generated torque and torque ripple rate shown in Fig. 10, the calculation results corresponding to harmonic phase differences θh of 70°, 60°, and 50° were obtained from the calculation results of the transition of the generated torque shown in Fig. 12. In each graph of Figs. 11 and 12, the horizontal axis scale is the same, and the vertical axis scale is also the same.

[0049] As in Fig. 7, the torque ripple rate increases as the harmonic phase difference θh increases beyond 90°, decreases as the harmonic phase difference θh decreases beyond 90°, and is at a minimum near 70°. The torque ripple rate increases as the harmonic phase difference θh decreases beyond 70°. The torque ripple rate when the harmonic phase difference θh is 50° is equivalent to the torque ripple rate when the harmonic phase difference θh is 90°.

[0050] From the above calculation results, when the harmonic phase difference θh is a phase difference of 50° or more and 90° or less, regardless of the rotation speed of the rotor 60, the generated torque can be maintained at a high level and the torque ripple rate can be reduced to a low value. Therefore, the above-mentioned predetermined phase difference is set to a phase difference of 50° or more and 90° or less. Note that the predetermined phase difference may be set to a phase difference of 60° or more and 80° or less, a phase difference of 65° or more and 75° or less, a phase difference of 60° or more and 70° or less, or a phase difference of 70° or more and 80° or less.

[0051] FIG. 13 is a diagram showing magnetic flux generated between the stator 50 and the rotor 60. In FIG. 13, for example, a U-phase current flows through the U-phase winding (U+, U-), and as shown by the dashed lines in the figure, magnetic fluxes φ1 and φ2 in opposite directions are generated between the stator 50 and the rotor 60 due to the flow of the U-phase current. In addition, a field current is induced in the field winding 70 by the harmonic current contained in the U-phase current, and a field flux φf shown by the dashed line in the figure is generated by the field current. In FIG. 13, one main pole portion 62 (left side of the figure) of the rotor 60 becomes an N pole, and the other main pole portion 62 (right side of the figure) becomes an S pole, and the rotor 60 rotates in a counterclockwise direction. Of the two main pole portions 62 arranged in the circumferential direction, the left main pole portion 62 is the main pole portion on the rotation direction side of the rotor 60, and the right main pole portion 62 is the main pole portion on the counter rotation direction side of the rotor 60.

[0052] 13, the harmonic phase difference θh is set to 90°. In this case, the electrical angle at which the envelope of the harmonic current has a maximum value is the electrical angle corresponding to the d-axis of the left main pole 62.

[0053] Fig. 14 is a diagram showing the composite magnetic flux of the magnetic fluxes φ1, φ2 and the field magnetic flux φf shown in Fig. 13. In Fig. 14, the composite magnetic flux is shown by a dashed line, and the magnetic flux generated by the harmonic current (hereinafter, harmonic field magnetic flux φh) is shown by a two-dot chain line.

[0054] As shown in Fig. 14, the resultant magnetic flux tends to increase in the circumferential direction at the portion on the rotation direction side among the tip portions of the left and right main pole portions 62, and decrease in the circumferential direction at the portion on the reverse rotation direction side. In this case, the harmonic interpolar magnetic flux φh is larger in the portion where there is a margin in the magnetic flux density than in the portion where the magnetic flux density of the resultant magnetic flux is large and close to magnetic saturation.

[0055] Fig. 15 is a diagram showing the state of the force acting on the tip portion in the radial direction of the main pole portion 62 due to the harmonic interpolar magnetic flux φh. Among the tip portions of the main pole portion 62, the force acting on the portion on the rotation direction side in the circumferential direction is denoted by F1, and the force acting on the portion on the reverse rotation direction side in the circumferential direction is denoted by F2. The circumferential components of the forces F1 and F2 become the torque ripple of the generated torque of the rotating electrical machine 40.

[0056] When the harmonic phase difference θh is 90°, "F1 < F2" holds due to the relationship of the magnetic flux density. As the harmonic phase difference θh is decreased from 90°, F2 decreases and F1 increases. When the harmonic phase difference θh is in the vicinity of 70°, "F1 ≒ F2" holds. In this case, the electrical angle at which the harmonic current (specifically, for example, the envelope of the harmonic current) reaches the maximum value in one cycle of the envelope of the harmonic current is the electrical angle corresponding to the end position t (see Fig. 13) on the rotation direction side of the rotor 60 in the circumferential direction among the left main pole portions 62. As the harmonic phase difference θh is decreased from 70°, "F1 > F2" holds, and the torque ripple turns to increase.

[0057] Of the tip portions of the main pole portion 62, the end portion on the rotation direction side has a higher magnetic flux density than the end portion on the counter-rotation direction side, and is less susceptible to magnetic flux fluctuations due to disturbances. For this reason, by making the harmonic phase difference θh smaller than 90° and approaching 70°, the torque ripple can be reduced. For example, the control device 30 can set the electrical angle at which the harmonic current (specifically, for example, the envelope of the harmonic current) is maximum in one cycle of the envelope of the harmonic current within a range from the electrical angle corresponding to the d-axis of the main pole portion 62 to the electrical angle corresponding to the end position t of the main pole portion 62 on the rotation direction side of the rotor 60 in the circumferential direction. Note that FIG. 16 shows the field magnetic flux φf when the harmonic phase difference θh is set to 70°, 90°, and 110°. Incidentally, the control device 30 may set the electrical angle at which the harmonic current (specifically, for example, the envelope of the harmonic current) is at its maximum value in one period of the envelope of the harmonic current within a range from the electrical angle corresponding to the d-axis of the main pole portion 62 to "the electrical angle corresponding to the above-mentioned end position t + 10°."

[0058] The predetermined phase difference for reducing the torque ripple rate while maintaining the maximum torque generated by the rotating electric machine 40 at a high level is a phase difference of 50° or more and 90° or less in electrical angle. (A1) Phase difference added by 180° (when N=1), (B1) Phase difference minus 180° (for N=-1), or (C1) Phase difference minus 180°×2 (when N=-2) In the cases (A1) and (B1), the torque ripple rate can be reduced while maintaining the maximum torque generation at a high level because, as shown in Fig. 6, one of the two envelopes of the harmonic current has a waveform in which the phase of the other envelope is shifted by 180°. Therefore, the control device 30 sets the predetermined phase difference as follows: (A1) A phase difference of 230° or more and 270° or less in electrical angle, (B1) A phase difference that is greater than or equal to -130° and less than or equal to -90° in electrical angle, or (C1) Phase difference between -310° and -270° electrical angle In this case, in each of the above-mentioned methods for setting the predetermined phase difference, a value obtained by adding 180°, subtracting 180°, or subtracting 360° may be used. Specifically, for example, in the case of (A1) above, the predetermined phase difference may be set to a phase difference of 240° or more and 260° or less, a phase difference of 245° or more and 255° or less, a phase difference of 240° or more and 250° or less, or a phase difference of 250° or more and 260° or less.

[0059] 17 shows a flowchart of the torque control process executed by the control device 30. This process is repeatedly executed at a predetermined control period, for example.

[0060] In step S10, the d- and q-axis command currents Id* and Iq* are calculated by the command current calculation unit 101. In step S11, the current control unit 102 and the three-phase conversion unit 103 calculate U-, V- and W-phase voltage command values ​​VU*, VV* and VW* based on the d- and q-axis command currents Id* and Iq*.

[0061] In step S12, the signal generating unit 104 generates drive signals for the upper and lower arm switches SUp to SWn of the U, V and W phases based on the U, V and W phase voltage command values ​​VU*, VV* and VW*. Then, the generated drive signals are input to the gates of the respective switches to perform switching control of the inverter 20.

[0062] According to the present embodiment described above in detail, it is possible to reduce the torque ripple of the torque generated by the rotating electric machine 40, and in turn to reduce the noise and vibration generated in association with the driving of the rotating electric machine 40. Furthermore, a simple parameter such as the harmonic phase difference θh can be used as a parameter for reducing the torque ripple, and the processing of the control device 30 can be simplified.

[0063] <Second embodiment> Hereinafter, the second embodiment will be described with reference to the drawings, focusing on the differences from the first embodiment. In this embodiment, as shown in Figures 18 and 19, a notch is formed at the tip of the main pole 62. This enhances the effect of reducing torque ripple.

[0064] Of the two main pole portions 62 aligned in the circumferential direction, one is referred to as a first main pole portion 162, and the other is referred to as a second main pole portion 262. The first main pole portions 162 and the second main pole portions 262 are alternately arranged in the circumferential direction.

[0065] The first main pole portion 162 has first and second ends 163a, 163b that face the stator 50 in the radial direction and that face both ends in the circumferential direction. The second end 163b faces the second main pole portion 262 in the circumferential direction, and the first end 163a is the end opposite the second main pole portion 262 in the circumferential direction. As shown in FIG. 20, the second end 163b of the first main pole portion 162 has a first notch 164 that extends from one end to the other end in the axial direction of the first main pole portion 162. The first notch 164 is a notch that opens radially outward (toward the stator) and circumferentially.

[0066] The second main pole portion 262 has first and second ends 263a, 263b that face the stator 50 in the radial direction and that face both ends in the circumferential direction. The first end 263a faces the first main pole portion 162 in the circumferential direction, and the second end 263b faces the opposite side of the first main pole portion 162 in the circumferential direction. A second notch 264 is formed in the first end 263a of the second main pole portion 262, and extends from one end to the other end in the axial direction of the second main pole portion 262. The second notch 264 is a notch that opens radially outward (toward the stator) and circumferentially.

[0067] In this embodiment, as shown in Fig. 19, when the width dimension in the circumferential direction of the first notch 164 is θnt, "1 / 3 x β<θnt<2 / 3 x β" is satisfied. Similarly, the width dimension in the circumferential direction of the second notch 264 is also set to "1 / 3 x β<θnt<2 / 3 x β". This is a setting for reducing torque ripple of the rotating electric machine 40. Particularly in this embodiment, the width dimension of each of the first notch 164 and the second notch 264 is set to β / 2. This enhances the effect of reducing torque ripple.

[0068] Note that θnt may be a value other than β / 2 within the range of “1 / 3×β<θnt<2 / 3×β.” If θnt is within the range of β×180° / 360°±β×60° / 360°, the torque ripple can be reduced.

[0069] Next, a description will be given of the influence that the first notch 164 and the second notch 264 have on the torque ripple. First, a case in which the first notch 164 and the second notch 264 are not present will be described with reference to Figs.

[0070] 21 shows the calculation results of the relationship between the harmonic phase difference θh and the torque generated by the rotating electrical machine 40, and the calculation results of the relationship between the harmonic phase difference θh and the torque ripple rate, when the rotation speed of the rotor 60 is set to 500 rpm. The reason why the rotation speed is set to a low speed such as 500 rpm is to make it easier to distinguish between the influence of the torque ripple caused by the frequency components of the harmonic current and the influence of the throttle ripple.

[0071] In FIG. 21, the 24Ap line shows the calculation result when the harmonic current has a peak value of 24% of the peak value of the fundamental current, and the 28Ap line shows the calculation result when the harmonic current has a peak value of 28% of the peak value of the fundamental current. The 24Ap line was calculated when the harmonic phase difference θh was 110°, 90°, 80°, 70°, and 60°, and the 28Ap line was calculated when the harmonic phase difference θh was 70°, 60°, 50°, and 40°. The peak value of the harmonic current is increased when the harmonic phase difference θh is less than 70° in order to minimize the variation in the maximum generated torque of the rotating electric machine 40. In each graph in FIG. 21, the horizontal axis scale is the same as in FIG. 10, and the vertical axis scale is also the same as in FIG. 10.

[0072] Among the calculation results of the generated torque and torque ripple rate shown in Fig. 21, the calculation results corresponding to the harmonic phase difference θh of 110°, 90°, and 70° were obtained from the calculation results of the transition of the generated torque shown in Fig. 22. In each graph in Fig. 22, the horizontal axis scale is the same as each other, and the vertical axis scale is also the same as each other.

[0073] Consider the case of "θh=110°, peak value=24A" in the graph shown in Fig. 22. In the upper graph of Fig. 23, the dashed line indicates the torque transition in the part surrounded by the dashed line in the upper graph of Fig. 22. Note that in each graph of Fig. 22, the horizontal axis scale is the same as each other, and the vertical axis scale is also the same as each other.

[0074] In the upper graph of Fig. 23, the solid line shows a torque transition in which the frequency components of the harmonic current have been removed from the torque transition shown by the dashed line. The torque transition in which the frequency components of the harmonic current have been removed includes the 12th-order throttle ripple component.

[0075] In the middle graph of Fig. 23, the solid line is the same as the solid line in the top graph, and the dashed line shows the torque transition with the 12th order throttle ripple component removed from the torque transition of the solid line. The torque transition with the 12th order throttle ripple component removed contains the 6th order throttle ripple component.

[0076] In the lower graph of FIG. 23, the dashed line is the same as the dashed line in the middle graph, and the solid line indicates a torque transition in which the sixth-order throttle ripple component has been removed from the torque transition of the dashed line.

[0077] In the graph shown in Fig. 22, let us consider the case of "θh = 70°" on the 28Ap line. In the upper graph of Fig. 24, the dashed line indicates the torque transition in the part surrounded by the dashed line in the lower graph of Fig. 22. Note that in each graph of Fig. 24, the horizontal axis scale is the same as each other, and the vertical axis scale is also the same as each other. Comparing the transitions of the dashed lines in the upper graphs of Figs. 24 and 23, it can be seen that the torque ripple caused by harmonic currents can be reduced by advancing the harmonic phase difference θh by about 40°.

[0078] In the upper graph of Fig. 24, the solid line shows a torque transition in which the frequency components of the harmonic current have been removed from the torque transition shown by the dashed line. The torque transition in which the frequency components of the harmonic current have been removed includes the 12th-order throttle ripple component.

[0079] In the middle graph of Fig. 24, the solid line is the same as the solid line in the upper graph, and the dashed line shows the torque transition with the 12th order throttle ripple component removed from the torque transition of the solid line. The torque transition with the 12th order throttle ripple component removed contains the 6th order throttle ripple component.

[0080] In the lower graph of FIG. 24, the dashed line is the same as the dashed line in the middle graph, and the solid line indicates a torque transition in which the sixth-order throttle ripple component has been removed from the torque transition of the dashed line.

[0081] 23 and 24, in a configuration in which the first notch 164 and the second notch 264 are not provided, the torque ripple caused by the throttle ripple component becomes large.

[0082] Next, a case where the first notch 164 and the second notch 264 are provided will be described with reference to FIGS.

[0083] Fig. 25 shows the calculation results of the relationship between the harmonic phase difference θh and the torque generated by the rotating electric machine 40, and the calculation results of the relationship between the harmonic phase difference θh and the torque ripple rate, when the rotation speed of the rotor 60 is 500 rpm. In Fig. 25, the 24 Ap line shows the calculation results when the harmonic current has a peak value that is 24% of the peak value of the fundamental current, and the 30 Ap line shows the calculation results when the harmonic current has a peak value that is 30% of the peak value of the fundamental current. In each graph in Fig. 25, the horizontal axis scale is the same as in Fig. 21, and the vertical axis scale is also the same as in Fig. 21.

[0084] Among the calculation results of the generated torque and torque ripple rate shown in Fig. 25, the calculation results corresponding to the harmonic phase difference θh of 110°, 90°, and 70° were obtained from the calculation results of the transition of the generated torque shown in Fig. 26. In each graph in Fig. 26, the horizontal axis scale is the same as each other, and the vertical axis scale is also the same as each other.

[0085] Consider the case of "θh=110°" on the 24Ap line in the graph shown in Fig. 26. In the upper graph of Fig. 27, the dashed line indicates the torque transition in the part surrounded by the dashed line in the upper graph of Fig. 26. Note that in each graph of Fig. 27, the horizontal axis scale is the same as each other, and the vertical axis scale is also the same as each other.

[0086] In the upper graph of Fig. 27, the solid line shows a torque transition in which the frequency components of the harmonic current have been removed from the torque transition shown by the dashed line. The torque transition in which the frequency components of the harmonic current have been removed includes the 12th-order throttle ripple component.

[0087] In the middle graph of Fig. 27, the solid line is the same as the solid line in the upper graph, and the dashed line shows the torque transition in which the 12th-order slot ripple component is removed from the torque transition of the solid line. The torque transition is similar before and after the removal of the 12th-order slot ripple component. Therefore, the first notch 164 and the second notch 264 reduce the slot ripple component.

[0088] In the lower graph of Fig. 27, the dashed line is the same as the dashed line in the middle graph, and the solid line shows the torque transition in which the sixth-order throttle ripple component is removed from the torque transition of the dashed line. The torque transition is similar before and after the removal of the sixth-order throttle ripple component.

[0089] In the graph shown in Fig. 26, let us consider the case of "θh = 70°" on the 30Ap line. In the upper graph of Fig. 28, the dashed line indicates the torque transition in the part surrounded by the dashed line in the lower graph of Fig. 26. Note that the horizontal and vertical scales are the same in each graph of Fig. 28. Comparing the transitions of the dashed lines in the upper graphs of Figs. 28 and 27, it can be seen that the torque ripple caused by harmonic currents can be reduced by advancing the harmonic phase difference θh by about 40°.

[0090] In the upper graph of Fig. 28, the solid line shows a torque transition in which the frequency components of harmonic currents have been removed from the torque transition shown by the dashed line. The torque transition in which the frequency components of harmonic currents have been removed includes the 12th-order throttle ripple component.

[0091] In the middle graph of Fig. 28, the solid line is the same as the solid line in the top graph, and the dashed line shows the torque transition with the 12th order slot ripple component removed from the torque transition of the solid line. The torque transition is similar before and after the removal of the 12th order slot ripple component. Therefore, the slot ripple component is reduced by the first notch 164 and the second notch 264. The torque transition with the 12th order slot ripple component removed includes the 6th order slot ripple component.

[0092] In the lower graph of FIG. 28, the dashed line is the same as the dashed line in the middle graph, and the solid line indicates a torque transition in which the sixth-order throttle ripple component has been removed from the torque transition of the dashed line.

[0093] 27 and 28, the configuration in which the first notch 164 and the second notch 264 are provided can suitably reduce the torque ripple caused by the throttle ripple component.

[0094] <Third embodiment> The third embodiment will be described below with reference to the drawings, focusing on the differences from the first embodiment. In this embodiment, when the phase of the fundamental wave current flowing through the stator winding 52 deviates from the reference phase θb, the control device 30 performs a process of adjusting the predetermined phase difference based on the amount of phase deviation of the fundamental wave current from the reference phase θb.

[0095] Fig. 29(a) shows a case where the phase of the fundamental current is the reference phase θb, and corresponds to Fig. 6(a) above. In other words, Fig. 29(a) shows a case where the zero-up cross timing of the fundamental current is the reference phase θb. Fig. 29(b) shows a case where the phase of the fundamental current is shifted from the reference phase θb. In the example shown in Fig. 29 (Fig. 6 above), the reference phase θb ​​is set to an electrical angle of 0°.

[0096] The example shown in Fig. 29(a) corresponds to the case shown in Fig. 13. Fig. 29(b) shows a case where the phase of the fundamental current leads from the reference phase θb. When performing field weakening control, for example, the control device 30 leads the phase of the fundamental current from the reference phase θb.

[0097] If the predetermined phase difference, which is the target value of the harmonic phase difference θh, is not adjusted even though the phase of the fundamental current has shifted from the reference phase θb, the torque ripple reduction effect may be reduced. For example, if the predetermined phase difference is not adjusted even though the phase of the fundamental current has been advanced from the reference phase θb ​​by the field weakening control, the phase of the harmonic field flux φh may be advanced too far from the appropriate phase, and the torque ripple reduction effect may be reduced. Therefore, the control device 30 performs an adjustment process for the predetermined phase difference.

[0098] 30 shows a flowchart of a torque control process including the above-mentioned adjustment process, which is executed by the control device 30. This process is repeatedly executed at a predetermined control period, for example. In step S20, the command current calculation unit 101 calculates a phase shift amount Δθ of the fundamental current with respect to the reference phase θb. In this embodiment, the sign of the shift amount Δθ is positive when the phase of the fundamental current leads the reference phase θb. The phase of the fundamental current may be calculated based on the detection value of the current sensor 21, for example.

[0099] In the command current calculation unit 101, the d- and q-axis command currents Id* and Iq* are calculated under the condition that the harmonic phase difference θh is a predetermined phase difference. In detail, when the calculated deviation amount Δθ is 0°, the predetermined phase difference is set to a phase difference equal to or larger than "50°+180°×N" and equal to or smaller than "90°+180°×N".

[0100] On the other hand, if the calculated deviation amount Δθ is a value other than 0, the predetermined phase difference is set to a phase difference equal to or greater than "50°+180°×N-Δθ" and equal to or less than "90°+180°×N-Δθ." After completing the process of step S20, the process proceeds to step S11.

[0101] According to the present embodiment described above, it is possible to prevent the harmonic phase difference θh from deviating from an appropriate phase difference that provides the torque ripple reduction effect.

[0102] <Other embodiments> Each of the above embodiments may be modified as follows.

[0103] In the second embodiment, when the calculated deviation amount Δθ is a value other than 0, the control device 30 may calculate a predetermined amount Δτ having an absolute value smaller than the deviation amount Δθ, and set the predetermined phase difference to a phase difference equal to or larger than "50°+180°×N-Δτ" and equal to or smaller than "90°+180°×N-Δτ". The predetermined amount Δτ may be set to, for example, "0.7×Δθ≦Δτ≦0.9".

[0104] In the second embodiment, the first notch 164 may be formed in a portion of the axial direction of the second end 163b of the first main pole portion 162, rather than from one end to the other in the axial direction. Also, the second notch 264 may be formed in a portion of the axial direction of the first end 263a of the second main pole portion 262, rather than from one end to the other in the axial direction.

[0105] The second winding portion 71b may be disposed closer to the stator 50 in the radial direction than the first winding portion 71a.

[0106] The capacitor 90 constituting the resonant circuit may be electrically connected in parallel to the first winding portion 71a instead of the second winding portion 71b. Also, in the resonant circuit, in the series connection of the first and second winding portions 71a, 71b, the anode of the diode 80 may be connected to the first winding portion 71a side, and the cathode of the diode 80 may be connected to the second winding portion 71b side.

[0107] The rotating electric machine is not limited to an inner rotor type rotating electric machine, but may be an outer rotor type rotating electric machine. In this case, the main pole portion protrudes radially inward from the rotor core.

[0108] The rotating electric machine is not limited to a star-connected rotating electric machine, but may be a delta-connected rotating electric machine.

[0109] In the first embodiment, the stator core may not be provided with teeth.

[0110] The rotating electric machine is not limited to a rotating electric machine used as an in-vehicle main engine, but may be, for example, a rotating electric machine used as an ISG (Integrated Starter Generator) that serves as both a motor and a generator.

[0111] The moving body on which the control system is mounted is not limited to a vehicle, but may be, for example, an aircraft or a ship. Furthermore, the control system is not limited to a system mounted on a moving body, but may be a stationary system.

[0112] The control device and the method described in the present disclosure may be realized by a special-purpose computer provided by configuring a processor and a memory programmed to execute one or more functions embodied in a computer program. Alternatively, the control device and the method described in the present disclosure may be realized by a special-purpose computer provided by configuring a processor with one or more dedicated hardware logic circuits. Alternatively, the control device and the method described in the present disclosure may be realized by one or more special-purpose computers configured by a combination of a processor and a memory programmed to execute one or more functions and a processor configured with one or more hardware logic circuits. In addition, the computer program may be stored in a computer-readable non-transitory tangible recording medium as instructions executed by the computer. [Explanation of symbols]

[0113] 20... inverter, 30... control device, 40... rotating electric machine, 50... stator, 52... stator winding, 60... rotor, 70... field winding.

Claims

1. A rotating electric machine (40) having a stator (50) including a stator winding (52) and a rotor (60) including a field winding (70); an inverter (20) electrically connected to the stator winding; A control device (30) for a rotating electric machine applied to a system including: The rotor has a rotor core (61) and main pole portions (62) provided at predetermined intervals in the circumferential direction and protruding in the radial direction from the rotor core, The field winding has a first winding portion (71a) and a second winding portion (71b) electrically connected in series, The first winding portion and the second winding portion are wound around the respective main pole portions, The rotor is a diode (80) electrically connected in parallel to the series connection of the first winding portion and the second winding portion; a capacitor (90) electrically connected in parallel to either the first winding portion or the second winding portion; having a composite current calculation unit that calculates a composite current obtained by superimposing a harmonic current for inducing a field current in the field winding on a fundamental current to be passed through the stator winding; a switch control unit that performs switching control of the inverter so as to pass the calculated combined current through the stator winding; Equipped with The composite current calculation unit calculating the composite current under the condition that the frequency of the envelope of the harmonic current is equal to the frequency of the fundamental current and that the phase difference (θh) between the envelope and the fundamental current is a predetermined phase difference; A control device for a rotating electric machine that sets the predetermined phase difference to a phase difference in electrical angle of "50°+180°×N" or more and "90°+180°×N" or less (N=0, 1, -1, -2).

2. The composite current calculation unit When the phase of the fundamental wave current is a reference phase (θb), the predetermined phase difference is set to a phase difference that is equal to or greater than "50°+180°×N" and equal to or less than "90°+180°×N" in electrical angle, 2 . The control device for a rotating electric machine according to claim 1 , wherein, when the phase of the fundamental current deviates from the reference phase, the predetermined phase difference is adjusted based on an amount of phase deviation of the fundamental current from the reference phase.

3. A rotating electric machine (40) having a stator (50) including a stator winding (52) and a rotor (60) including a field winding (70); an inverter (20) electrically connected to the stator winding; A control device (30) for a rotating electric machine applied to a system including: The rotor has a rotor core (61) and main pole portions (62) provided at predetermined intervals in the circumferential direction and protruding in the radial direction from the rotor core, The field winding has a first winding portion (71a) and a second winding portion (71b) electrically connected in series, The first winding portion and the second winding portion are wound around the respective main pole portions, The rotor is a diode (80) electrically connected in parallel to the series connection of the first winding portion and the second winding portion; a capacitor (90) electrically connected in parallel to either the first winding portion or the second winding portion; having a composite current calculation unit that calculates a composite current obtained by superimposing a harmonic current for inducing a field current in the field winding on a fundamental current to be passed through the stator winding; a switch control unit that performs switching control of the inverter so as to pass the calculated combined current through the stator winding; Equipped with the composite current calculation unit calculates the composite current by imposing a first condition that a frequency of an envelope of the harmonic current is equal to a frequency of the fundamental current, and a second condition; The control device for a rotating electric machine, wherein the second condition is a condition that the electrical angle at which the harmonic current is at its maximum value is within a range from an electrical angle corresponding to the d-axis of the main pole portion to an electrical angle corresponding to near the end position of the main pole portion in the circumferential direction on the side in the rotational direction of the rotor.

4. 2 . The control device for a rotating electric machine according to claim 1 , wherein the composite current calculation unit sets the predetermined phase difference to a phase difference that is equal to or greater than 60° and equal to or smaller than 80° in electrical angle.

5. The stator includes: A back yoke (51a); A plurality of teeth (51b) are arranged in a circumferential direction and protrude from the back yoke toward the rotor in a radial direction; having Of the two main pole portions arranged in the circumferential direction, one is a first main pole portion (162) and the other is a second main pole portion (262), A first notch (164) extending in the axial direction is formed in an end (163b) of the first main pole portion, the end (163b) facing the stator in the radial direction and facing the second main pole portion in the circumferential direction, The control device for a rotating electric machine according to any one of claims 1 to 4, wherein an end (263) a of the second main pole portion, which faces the stator in the radial direction and faces the first main pole portion in the circumferential direction, is formed with a second notch (264) extending in the axial direction.

6. 6. The control device for a rotating electric machine as described in claim 5, wherein, when a one-slot pitch of the stator is β and a circumferential width of each of the first notch and the second notch is θnt, "1 / 3 x β < θnt < 2 / 3 x β".

7. The control device for a rotating electric machine according to claim 6 , wherein θnt=β / 2.

8. A rotating electric machine (40) having a stator (50) including a stator winding (52) and a rotor (60) including a field winding (70); an inverter (20) electrically connected to the stator winding; A computer (31); In a program applied to a system comprising: The rotor has a rotor core (61) and main pole portions (62) provided at predetermined intervals in the circumferential direction and protruding in the radial direction from the rotor core, The field winding has a first winding portion (71a) and a second winding portion (71b) electrically connected in series, The first winding portion and the second winding portion are wound around the respective main pole portions, The rotor is a diode (80) electrically connected in parallel to the series connection of the first winding portion and the second winding portion; a capacitor (90) electrically connected in parallel to either the first winding portion or the second winding portion; having The computer includes: a composite current calculation process for calculating a composite current obtained by superimposing a harmonic current for inducing a field current in the field winding on a fundamental current to be passed through the stator winding; A process of performing switching control of the inverter so as to pass the calculated combined current through the stator winding; Run the command, In the composite current calculation process, calculating the composite current under the condition that the frequency of the envelope of the harmonic current is equal to the frequency of the fundamental current and that the phase difference (θh) between the envelope and the fundamental current is a predetermined phase difference; A program for setting the predetermined phase difference to a phase difference equal to or greater than "50°+180°×N" and equal to or less than "90°+180°×N" (N=0, 1, -1, -2) in electrical angle.

Images