Rotary electric machine

Abstract

To provide a rotary electric machine which can improve torque and an efficiency, and which can reduce a ripple in torque.SOLUTION: A rotary electric machine includes a stator and a rotor. The rotor includes: a main polarization portion which is provided for each magnetic pole arranged side by side in the circumferential direction, and which protrudes in the radial direction; and a field-magnetic winding wound around each main polarization portion. The field-magnetic winding includes a first winding portion 71 and a second winding portion 72 both connected in series. The rotary electric machine includes a parallel-connection diode 80 connected in parallel with the second winding portion 72.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present disclosure relates to a wound field type rotating electric machine. [Background technology]

[0002] Conventionally, as described in, for example, Patent Document 1, a wound field type rotating electric machine including a stator and a rotor has been known. The rotor has main pole parts provided for each of the magnetic poles arranged in the circumferential direction and protruding in the radial direction, and a field winding wound around each main pole part. A current including a high-frequency current flows through the stator winding provided in the stator. This induces a voltage in the field winding, and a field current flows through the field winding. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 6969529 Summary of the Invention [Problem to be solved by the invention]

[0004] There is still room for improvement in technology for improving the torque of a rotating electrical machine and reducing torque pulsation and loss by reducing field current pulsation.

[0005] A primary object of the present disclosure is to provide a rotating electric machine capable of increasing a field current flowing through a field winding. [Means for solving the problem]

[0006] The present disclosure provides a rotor including a stator having stator windings; a rotor facing the stator in a radial direction; In a rotating electric machine comprising: The rotor is A main pole portion is provided for each of the magnetic poles arranged in the circumferential direction and protrudes in the radial direction; A field winding wound around each of the main pole portions; having the field winding has a first winding portion and a second winding portion, an electrical path connected in parallel to at least one of the first winding portion and the second winding portion; The electrical pathway is configured to carry electrical current through it in one direction.

[0007] By providing the electric path, the field current flowing through the first and second windings can be increased and the field current pulsation can be reduced, resulting in improved torque of the rotating electric machine and reduced torque pulsation and loss. [Brief description of the drawings]

[0008] [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] 4 is a time chart showing changes in current and torque flowing through the first and second windings. [Figure 6] FIG. 4 is a diagram showing an electric circuit provided in a rotor according to a comparative example. [Figure 7] 5 is a time chart showing changes in current and torque flowing through first and second windings in a comparative example. [Figure 8] FIG. 11 is a diagram showing an electric circuit provided in a rotor according to a second embodiment. [Figure 9] 4 is a time chart showing changes in current and torque flowing through the first and second windings. [Figure 10] FIG. 11 is a diagram showing an electric circuit provided in a rotor according to a third embodiment. [Figure 11] 4 is a time chart showing changes in current and torque flowing through the first and second windings. [Figure 12] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to a fourth embodiment. [Figure 13]4 is a time chart showing changes in current and torque flowing through the first and second windings. [Figure 14] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to a fifth embodiment. [Figure 15] 4 is a time chart showing changes in current and torque flowing through the first and second windings. [Figure 16] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Figure 17] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Figure 18] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Figure 19] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Figure 20] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Figure 21] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Figure 22] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Figure 23] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Figure 24] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Diagram 25] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Figure 26] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Figure 27] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Figure 28] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Figure 29] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Diagram 30] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Diagram 31] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Diagram 32] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Diagram 33] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Diagram 34] FIG. 13 is a diagram showing an electric circuit provided in a rotor according to another embodiment. [Diagram 35] FIG. 11 is a cross-sectional view of a rotor and a stator according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] 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.

[0010] First Embodiment A first embodiment of a rotating electric machine according to the present disclosure will be described below with reference to the drawings. The rotating electric machine constitutes 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.

[0011] 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 self-excited field winding type synchronous machine. For example, a mechanically and electrically integrated drive device may be configured by including the rotating electric machine 40, the inverter 20, and the control device 30, or the rotating electric machine 40, the inverter 20, and the control device 30 may each be configured by a respective component.

[0012] 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.

[0013] 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.

[0014] The rotor 60 includes a rotor core 61 and a field winding 70. The field winding 70 is made of, for example, aluminum wire, copper wire, or CNT (carbon nanotube). A 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 42.

[0015] 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 antiparallel to each of the switches SUp to SWn. Each of the switches SUp to SWn may be, for example, an N-channel MOSFET.

[0016] The collectors, which are high potential terminals of the U-, V-, and W-phase upper arm switches SUp, SVp, and SWp, are connected to the positive terminal of a DC power supply 10. The emitters, which are low potential terminals of the U-, V-, and W-phase lower arm switches SUn, SVn, and SWn, are connected to the negative terminal of the DC power supply 10. A smoothing capacitor 11 is connected in parallel to the DC power supply 10.

[0017] Next, the stator 50 and the rotor 60 will be described with reference to FIG.

[0018] 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.

[0019] 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 and aligned in the circumferential direction. The stator winding 52 is formed by accommodating the phase windings of each phase in each slot 54 in a predetermined order.

[0020] 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.

[0021] The field winding 70 includes a first winding portion 71 and a second winding portion 72. In each main pole portion 62, the first winding portion 71 is wound radially outward, and the second winding portion 72 is wound radially inward from the first winding portion 71. In each main pole portion 62, the winding directions of the first winding portion 71 and the second winding portion 72 are the same. In addition, among the main pole portions 62 adjacent in the circumferential direction, the winding directions of the winding portions 71, 72 wound around one of the main pole portions 62 are opposite to the winding directions of the winding portions 71, 72 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.

[0022] Returning to the explanation of FIG. 2, the control system includes a current sensor 21, an angle sensor 22, a voltage sensor 23, and a temperature 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, and is, for example, a resolver. In this embodiment, the voltage sensor 23 detects the voltage of the DC power supply 10. The temperature sensor 24 detects the temperature of the rotating electric machine, etc., and is, for example, a thermistor. The detection values ​​of the sensors 21 to 24 are input to the control device 30.

[0023] 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 physical 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, the functions 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 a program for control processing of the rotating electric machine 40. 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.

[0024] Next, the electric circuit on the rotor 60 side, which is a characteristic configuration of this embodiment, will be described. Fig. 4 is a diagram showing the electric circuit on the rotor 60 side having first and second winding portions 71, 72. The first winding portion 71 shown in Fig. 4 is a series connection of the first winding portions 71 wound around each main pole portion 62, and the second winding portion 72 shown in Fig. 4 is a series connection of the second winding portions 72 wound around each main pole portion 62.

[0025] The rotor 60 includes a parallel diode 80 (corresponding to an "electrical path") and a series capacitor 100. The parallel diode 80 is connected in parallel to the second winding portion 72. More specifically, the anode of the parallel diode 80 is connected to a first end 72a of the second winding portion 72, and the cathode of the parallel diode 80 is connected to a second end 72b of the second winding portion 72. This forms a closed circuit including the second winding portion 72 and the parallel diode 80. In this closed circuit, a current flows in one direction, from the anode side to the cathode side of the parallel diode 80.

[0026] The second end 72b of the second winding portion 72 is connected to the first end 71a of the first winding portion 71. The second end 71b of the first winding portion 71 is connected to the first end 72a of the second winding portion 72 via the series capacitor 100. This forms a closed circuit including the first winding portion 71, the second winding portion 72, and the series capacitor 100. In this embodiment, the number of turns of the second winding portion 72 is greater than the number of turns of the first winding portion 71. The series capacitor 100 is, for example, a ceramic capacitor or a film capacitor.

[0027] The control device 30 generates drive signals to turn on and off each of the switches SUp to SWn that constitute the inverter 20. In particular, the control device 30 generates drive signals to turn on and off each of the arm switches SUp to SWn and supplies the generated drive signals to the gates of 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. As a result, in each phase, the upper arm switches and the lower arm switches are alternately turned on with dead times therebetween.

[0028] The control device 30 turns on and off the switches SUp to SWn so as to pass a composite current of a fundamental current and a high-frequency current (specifically, a high-frequency excitation current) having a frequency higher than that of the fundamental current 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 high-frequency current is a current that mainly serves to excite the first and second winding portions 71 and 72 that constitute the field winding 70, thereby inducing 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.

[0029] The high-frequency current passed through the stator winding 52 may be a harmonic current whose fluctuating frequency is N times (N is an integer equal to or greater than 2) the frequency of the fundamental current, or a current whose fluctuating frequency is different from N times the frequency of the fundamental current.

[0030] According to the circuit shown in FIG. 4, the DC component of the field current can be increased more than in the comparative example shown in FIG. 6. The reason why the DC component can be increased will be described with reference to FIG. 5. FIG. 5 shows the transition of the current IL1 flowing through the first winding portion 71, the current IL2 flowing through the second winding portion 72, and the torque of the rotating electric machine 40 in one electrical angle period of the rotor 60 when the rotation speed of the rotor 60 is 3000 rpm and the excitation frequency (specifically, the frequency of the high-frequency current) is 2.4 kHz. As shown in FIG. 4, the positive direction of the current IL1 flowing through the first winding portion 71 is from the second end 71b side to the first end 71a side of the first winding portion 71. The positive direction of the current IL2 flowing through the second winding portion 72 is from the second end 72b side to the first end 72a side of the second winding portion 72.

[0031] When a high-frequency current flows through the stator winding 52, a voltage is induced in the first and second winding portions 71 and 72, causing a field current to flow. The induced voltages in the first and second winding portions 71 and 72 are, for example, in phase. The currents IL1 and IL2 flowing through the first and second winding portions 71 and 72 contain frequency components of the high-frequency current.

[0032] In the first period P1, a current I1 flows from the first winding portion 71 to the second winding portion 72.

[0033] In a second period P2 in which the current IL2 flowing through the second winding portion 72 is greater than the current IL1 flowing through the first winding portion 71, a current I2a flows through a closed circuit including the second winding portion 72 and the parallel diode 80. When the voltage across the second winding portion 72 exceeds the forward voltage Vf of the parallel diode 80, a current flows through the closed circuit.

[0034] Since a current continues to flow through the closed circuit including the second winding portion 72 and the parallel diode 80, it is possible to increase the DC component of the field current. As a result, it is possible to increase the DC component of the magnetic flux of the rotor 60, and therefore the torque of the rotating electric machine 40.

[0035] During part of the second period P2, a part of the current I2b flowing in the closed circuit including the second winding portion 72 and the parallel diode 80 flows through the first winding portion 71. In this case, the sign of the change in the current IL1 flowing through the first winding portion 71 (i.e., the increase or decrease in the current IL1) is different from the sign of the change in the current IL2 flowing through the second winding portion 72 (i.e., the increase or decrease in the current IL2). This makes it possible to reduce the pulsation of the field current, which is the sum of the currents IL1 and IL2, and therefore the torque pulsation of the rotating electric machine 40.

[0036] Fig. 6 shows the electric circuit on the rotor side in the comparative example. This electric circuit includes a diode 74, a first capacitor 74, and a second capacitor 75. Fig. 7 shows the transition of the current IL1 flowing through the first winding portion 71, the current IL2 flowing through the second winding portion 72, and the torque of the rotating electric machine in one period of the rotor electrical angle when the rotor rotation speed is 3000 rpm and the excitation frequency is 2.4 kHz. One graduation on the vertical axis of the current and torque in Fig. 7 is the same as one graduation on the vertical axis of the current and torque in Fig. 5 above.

[0037] In the comparative example, the DC component of the field current is increased mainly by charging and discharging first capacitor 74. The left column of Fig. 7 shows a time chart in which the capacitance of first capacitor 74 is set so that the torque of the rotating electric machine in the comparative example is equivalent to that of this embodiment. In this case, the capacitance of first capacitor 74 in the comparative example is larger than the capacitance of series capacitor 100 in this embodiment, and more specifically, is approximately three times the capacitance of series capacitor 100. As a result, first capacitor 74 in the comparative example is larger than series capacitor 100 in this embodiment.

[0038] 7 shows a timing chart for the case where the capacitance of first capacitor 74 in the comparative example is approximately the same as the capacitance of series capacitor 100 in this embodiment. When the capacitances are approximately the same, the torque of the rotating electric machine in the comparative example is significantly lower than the torque of rotating electric machine 40 of this embodiment, and specifically, the torque is lowered to, for example, about ⅓ of that of this embodiment.

[0039] By increasing the number of turns of the second winding section 72, which has less current pulsation and a large DC component, compared to the number of turns of the first winding section 71, it is possible to enhance the effect of reducing the pulsation of the field current, the effect of reducing the torque pulsation due to the increase in the DC component, and the effect of increasing the torque. In addition, it is possible to obtain the effect of reducing losses (for example, losses in the rotor 60, specifically, for example, copper loss and iron loss) by reducing the pulsation of the field current.

[0040] According to the present embodiment described above in detail, it is possible to increase the field current and reduce the pulsation of the field current while reducing the capacitance of the capacitor provided in the rotor 60. This makes it possible to improve the torque of the rotating electric machine 40 and reduce torque pulsation and loss by reducing the field current pulsation.

[0041] <Second embodiment> The second embodiment will be described below with reference to the drawings, focusing on the differences from the first embodiment. In this embodiment, as shown in FIG. 8, a series diode 90 (corresponding to a "regulating portion") is provided on the rotor 60 instead of the series capacitor 100. The anode of the series diode 90 is connected to the first end 72a of the second winding portion 72. The cathode of the series diode 90 is connected to the second end 71b of the first winding portion 71. This forms a closed circuit including the first winding portion 71, the second winding portion 72, and the series diode 90. The anodes of the parallel diode 80 and the series diode 90 are electrically connected to each other.

[0042] 9 shows changes in the current IL1 flowing through the first winding portion 71, the current IL2 flowing through the second winding portion 72, and the torque of the rotating electric machine 40 over one period of the electrical angle of the rotor 60 when the rotational speed of the rotor 60 is 3000 rpm and the excitation frequency is 2.4 kHz. One graduation on the vertical axis of the current and torque in Fig. 9 is the same as one graduation on the vertical axis of the current and torque in Fig. 5 above.

[0043] The series diode 90 blocks current flowing in the first winding portion 71 in a direction from the first end 71a to the second end 71b. This rectifies the current IL1 flowing through the first winding portion 71, reducing pulsation of the current IL1 flowing through the first winding portion 71. The rectification of the current IL1 flowing through the first winding portion 71 changes the current IL2 flowing through the second winding portion 72. The above-described effect of rectification reduces pulsation of the field current, and ultimately reduces torque pulsation of the rotating electric machine 40.

[0044] Of the first and second winding parts 71, 72, a series diode 90 is connected in series to the first winding part 71 that has stronger magnetic coupling with the stator winding 52, and a parallel diode 80 is connected in parallel to the second winding part 72 that has weaker magnetic coupling. Since the effect of the voltage induced in the winding part with weaker magnetic coupling is smaller than that of the winding part with stronger magnetic coupling, the parallel diode 80 is connected in parallel to the second winding part 72 that has weaker magnetic coupling, thereby further enhancing the effect of reducing pulsation of the field current and the effect of increasing the DC component. In this embodiment, of the first and second winding parts 71, 72, the second winding part 72 that is farther away from the stator winding 52 in the radial direction has weaker magnetic coupling than the first winding part 71.

[0045] Of the first and second winding sections 71, 72, the second winding section 72, which has weaker magnetic coupling with the stator winding 52, has a greater number of turns than the first winding section 71, which has stronger magnetic coupling. Increasing the number of turns of the second winding section 72, which has a relatively small current pulsation and a relatively large DC component of the current, can further enhance the effect of reducing field current pulsation and increasing the DC component, as well as the effect of reducing current pulsation, the effect of reducing torque pulsation due to the increase in the DC component, and the effect of increasing torque. Reducing current pulsation also contributes to improving efficiency. In addition, the electrical load on the diodes 80, 90 is reduced.

[0046] <Modification of the second embodiment> The parallel diode 80 and the series diode 90 may be arranged in the opposite directions. More specifically, the cathode of the parallel diode 80 is connected to the first end 72a of the second winding portion 72, and the anode of the parallel diode 80 is connected to the second end 72b of the second winding portion 72. The cathode of the series diode 90 is connected to the first end 72a of the second winding portion 72, and the anode of the series diode 90 is connected to the second end 71b of the first winding portion 71. In this case, the cathodes of the parallel diode 80 and the series diode 90 are electrically connected to each other.

[0047] The parallel diode 80 and the series diode 90 are not limited to diodes as long as they are elements that pass current in one direction. For example, an element having a first terminal and a second terminal, allowing current to flow from the first terminal to the second terminal and preventing current from flowing from the second terminal to the first terminal may be used as the parallel diode 80 and the series diode 90. For example, the parallel diode 80 and the series diode 90 may be an element capable of preventing current from flowing in the reverse direction, such as a body diode of a MOSFET (e.g., an N-channel MOSFET). In this case, the control device 30 may perform synchronous rectification by turning on and off the MOSFET. The MOSFET may be turned on and off by a circuit built into the rotor 60, or by wireless communication via a transformer or the like.

[0048] <Third embodiment> The third embodiment will be described below with reference to the drawings, focusing on the differences from the second embodiment. In this embodiment, as shown in FIG. 10, a parallel capacitor 110 connected in parallel to a series diode 90 is provided on a rotor 60. A first end of the parallel capacitor 110 is connected to a second end 71b of the first winding portion 71, and a second end of the parallel capacitor 110 is connected to a first end 72a of the second winding portion 72. This forms a closed circuit including the first winding portion 71, the second winding portion 72, and the parallel capacitor 110. In this embodiment, the capacitance of the parallel capacitor 110 is smaller than the capacitance of the series capacitor 100 shown in FIG. 4 above, and specifically, for example, is ½ or less, ⅓ or less, or ¼ or less of the capacitance of the series capacitor 100. The parallel capacitor 110 is, for example, a ceramic capacitor or a film capacitor.

[0049] 11 shows changes in the current IL1 flowing through the first winding portion 71, the current IL2 flowing through the second winding portion 72, and the torque of the rotating electric machine 40 over one period of the electrical angle of the rotor 60 when the rotational speed of the rotor 60 is 3000 rpm and the excitation frequency is 2.4 kHz. One graduation on the vertical axis of the current and torque in Fig. 11 is the same as one graduation on the vertical axis of the current and torque in Fig. 9 above.

[0050] By providing the parallel capacitor 110, the impedance of the closed circuit including the parallel capacitor 110 is reduced, making it easier for a current to flow through this closed circuit. This allows the DC component of the field current to be increased. In addition, the parallel capacitor 110 reduces the change in the current IL1 flowing through the first winding portion 71 and the current IL2 flowing through the second winding portion 72, making the current waveform smoother and changing the phase of the current waveform. As the current waveform becomes smoother and the phase of the current waveform changes, the pulsation of the field current is reduced and the pulsation of the torque determined by the sum of the two winding portions 71 and 72 is reduced. The reduction in current pulsation also contributes to improving efficiency. In addition, the electrical load on the diodes 80 and 90 is reduced. Compared to the comparative example described in the first embodiment, the electrical load on the parallel capacitor 110 is also reduced in this embodiment.

[0051] <Fourth embodiment> The fourth embodiment will be described below with reference to the drawings, focusing on the differences from the third embodiment. In this embodiment, as shown in Fig. 12, a capacitor 120 connected in parallel to the second winding portion 72 is provided on the rotor 60. In this embodiment, the capacitor 120 is referred to as the winding-side capacitor 120. In this embodiment, the capacitance of the winding-side capacitor 120 is equal to the capacitance of the series capacitor 100. The winding-side capacitor 120 is, for example, a ceramic capacitor or a film capacitor.

[0052] Fig. 13 shows changes in the current IL1 flowing through the first winding portion 71, the current IL2 flowing through the second winding portion 72, and the torque of the rotating electric machine 40 over one period of the electrical angle of the rotor 60 when the rotational speed of the rotor 60 is 3000 rpm and the excitation frequency is 2.4 kHz. One graduation on the vertical axis of the current and torque in Fig. 13 is the same as one graduation on the vertical axis of the current and torque in Fig. 11 above.

[0053] By providing the winding-side capacitor 120, it is possible to set the impedance of the closed circuit formed by the first and second winding portions 71, 72 individually, and to shift the phase of the current pulsation, thereby reducing the pulsation of the field current. As a result, it is possible to reduce the torque pulsation of the rotating electric machine 40. Furthermore, arranging the winding-side capacitor 120 in the vicinity of the parallel diode 80 also leads to a reduction in the electrical load on the diodes 80, 90. Compared to the comparative example described in the first embodiment, the electrical load on the parallel capacitor 110 is also reduced in this embodiment.

[0054] <Fifth embodiment> The fifth embodiment will be described below with reference to the drawings, focusing on the differences from the fourth embodiment. In this embodiment, as shown in Fig. 14, a capacitor 121 is provided in the rotor 60 instead of the parallel capacitor 110. In this embodiment, the capacitor 121 is referred to as the first winding side capacitor 121, and the winding side capacitor 120 is referred to as the second winding side capacitor 120. The first winding side capacitor 121 is connected in parallel to the first winding portion 71. The first winding side capacitor 121 is, for example, a ceramic capacitor or a film capacitor.

[0055] 15 shows changes in the current IL1 flowing through the first winding portion 71, the current IL2 flowing through the second winding portion 72, and the torque of the rotating electric machine 40 over one period of the electrical angle of the rotor 60 when the rotational speed of the rotor 60 is 3000 rpm and the excitation frequency is 2.4 kHz. One graduation on the vertical axis of the current and torque in Fig. 15 is the same as one graduation on the vertical axis of the current and torque in Fig. 13 above.

[0056] By providing the second winding side capacitor 120 and the first winding side capacitor 121, the impedance of the closed circuit formed by the first and second winding parts 71 and 72 can be set individually, and the phase of the current pulsation can be shifted, thereby reducing the pulsation of the field current. As a result, the torque pulsation of the rotating electric machine 40 can be reduced. In addition, the parallel capacitor 110 shown in the fourth embodiment is applied with a voltage obtained by adding up the voltage of the first winding part 71 and the voltage of the second winding part 72, whereas the first winding side capacitor 121 in this embodiment is applied with only the voltage of the first winding part 71, thereby reducing the load on the first winding side capacitor 121. In addition, arranging the capacitors 120 and 121 near the parallel diode 80 and the series diode 90 also reduces the electrical load on the diodes 80 and 90.

[0057] <Other embodiments> Each of the above embodiments may be modified as follows.

[0058] The circuit shown in FIG. 16 is a circuit in which a capacitor 121 is connected in parallel to the first winding portion 71 in the circuit shown in FIG.

[0059] The circuit shown in FIG. 17 is a circuit in which a capacitor 121 is connected in parallel to the first winding portion 71 instead of the second winding portion 72 in the circuit shown in FIG.

[0060] The circuit shown in FIG. 18 is a circuit in which a capacitor 120 is connected in parallel to the second winding portion 72 in the circuit shown in FIG.

[0061] The circuit shown in FIG. 19 is a circuit in which a capacitor 121 is connected in parallel to the first winding portion 71 in the circuit shown in FIG.

[0062] 20 is a circuit in which a parallel diode 81 is connected in parallel to the first winding portion 71 instead of the second winding portion 72 in the circuit shown in Fig. 4. The anode of the parallel diode 81 is connected to the first end 71a of the first winding portion 71, and the cathode of the parallel diode 81 is connected to the second end 71b of the first winding portion 71.

[0063] The circuit shown in FIG. 21 is a circuit in which a capacitor 121 is connected in parallel to the first winding portion 71 in the circuit shown in FIG.

[0064] The circuit shown in FIG. 22 is a circuit in which a capacitor 120 is connected in parallel to the second winding portion 72 in the circuit shown in FIG.

[0065] The circuit shown in FIG. 23 is a circuit in which a parallel diode 81 is connected in parallel to the first winding portion 71 in the circuit shown in FIG.

[0066] The circuit shown in Fig. 24 is a circuit in which a capacitor 121 is connected in parallel to the first winding portion 71 in the circuit shown in Fig. 23. Note that in the circuit of Fig. 24, a capacitor may be connected in parallel to the second winding portion 72 instead of the first winding portion 71.

[0067] The circuit shown in FIG. 25 is a circuit in which a capacitor 120 is connected in parallel to the second winding portion 72 in the circuit shown in FIG.

[0068] 26 is a circuit similar to that shown in Fig. 20, except that the first end 71a of the first winding portion 71 and the second end 72b of the second winding portion 72 are connected by a series diode 91. The anode of the series diode 91 is connected to the first end 71a of the first winding portion 71, and the cathode of the series diode 91 is connected to the second end 72b of the second winding portion 72.

[0069] The circuit shown in Fig. 27 is a circuit in which a capacitor 121 is connected in parallel to the first winding portion 71 in the circuit shown in Fig. 26. Note that in the circuit of Fig. 27, a capacitor may be connected in parallel to the second winding portion 72 instead of the first winding portion 71.

[0070] The circuit shown in FIG. 28 is a circuit in which a capacitor 120 is connected in parallel to the second winding portion 72 in the circuit shown in FIG.

[0071] The circuit shown in FIG. 29 is a circuit in which a series diode 91 is provided between the first end 71a of the first winding portion 71 and the second end 72b of the second winding portion 72, instead of between the second end 71b of the first winding portion 71 and the first end 72a of the second winding portion 72 in the circuit shown in FIG. 8 above.

[0072] The circuit shown in Fig. 30 is a circuit in which a capacitor 121 is connected in parallel to the first winding portion 71, and a capacitor 120 is connected in parallel to the second winding portion 72 in the circuit shown in Fig. 29. Note that in the circuit shown in Fig. 30, either of the capacitors 120 and 121 does not necessarily have to be provided.

[0073] 26 to 30, the orientations of the diodes 81, 91 may be reversed. Taking Fig. 26 as an example, the cathode of the parallel diode 81 is connected to the first end 71a of the first winding portion 71, and the anode of the parallel diode 81 is connected to the second end 71b of the first winding portion 71. In addition, the cathode of the series diode 91 is connected to the first end 71a of the first winding portion 71, and the anode of the series diode 91 is connected to the second end 71b of the first winding portion 71.

[0074] 4 above, series capacitor 100 does not have to be provided. In this case, second end 71b of first winding portion 71 and first end 72a of second winding portion 72 are connected together. In this case, as shown in FIG 31, a parallel diode 81 may be connected in parallel to first winding portion 71, instead of second winding portion 72.

[0075] The circuit shown in FIG. 32 is a circuit in which a capacitor 121 is connected in parallel to the first winding portion 71 and a capacitor 120 is connected in parallel to the second winding portion 72 in the circuit shown in FIG.

[0076] The circuit shown in FIG. 33 is a circuit in which a parallel diode 80 is connected in parallel to the second winding portion 72 in the circuit shown in FIG.

[0077] The circuit shown in FIG. 34 is a circuit in which a capacitor 121 is connected in parallel to the first winding portion 71 and a capacitor 120 is connected in parallel to the second winding portion 72 in the circuit shown in FIG.

[0078] The number of turns of the second winding portion 72 may be less than the number of turns of the first winding portion 71, or may be the same as the number of turns of the first winding portion 71.

[0079] A rotor having a field winding 170 as shown in Fig. 35 may be used. In detail, the field winding 170 includes a first winding portion 171 wound around the main pole portion 62, and a second winding portion 172 wound around the outside of the first winding portion 171.

[0080] 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.

[0081] The rotating electric machine is not limited to a star-connected rotating electric machine, but may be a delta-connected rotating electric machine.

[0082] The stator core may not be provided with teeth.

[0083] 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 is a motor / generator, or a rotating electric machine for an auxiliary machine.

[0084] In each of the above embodiments, the circuit diagram shows a single capacitor connected to the same location of the rotor electric circuit, but the capacitor connected to the same location may be a parallel connection of multiple capacitors. For example, in the electric circuit shown in FIG. 4, a parallel or series connection of multiple capacitors may be used instead of one capacitor 100. A required capacitance may be secured by multiple capacitors, or redundancy may be ensured by connecting multiple capacitors in parallel or in series. It has been described that a capacitor becomes larger as the capacitance increases, but even if the capacitance is increased by connecting multiple capacitors in parallel to increase the capacitance of the capacitor, the volume occupied by the capacitor required for that increases as the required capacitance increases.

[0085] Even if the position of the first winding and the series diode are swapped, the rotor electrical circuit is equivalent and the same effect can be obtained.

[0086] A small capacitance capacitor may be placed in series with the windings or diodes, and the capacitor may be used to adjust impedance or phase. The same effect can also be achieved by placing a resistor with a small resistance, such as a fuse, in series with the windings or diodes.

[0087] 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.

[0088] Characteristic configurations extracted from each of the above-described embodiments will be described below. [Configuration 1] a stator (50) having a stator winding (52); a rotor (60) facing the stator in the radial direction; In a rotating electric machine (40) comprising: The rotor is A main pole portion (62) is provided for each of the magnetic poles arranged in the circumferential direction and protrudes in the radial direction; A field winding (70) wound around each of the main pole portions; having The field winding has a first winding portion (71) and a second winding portion (72), an electric path (80, 81) connected in parallel to at least one of the first winding portion and the second winding portion; A rotating electric machine, wherein the electrical path is configured to allow current to flow therethrough in one direction. [Configuration 2] The rotating electric machine according to configuration 1, further comprising a regulating section (90, 91) connected in series to one of the first winding section and the second winding section to which the electrical path is not connected in parallel, and causing a current to flow in one direction. [Configuration 3] 3. The rotating electric machine according to configuration 1 or 2, wherein the electrical path includes a parallel diode that is a diode connected in parallel to at least one of the first winding portion and the second winding portion. [Configuration 4] 3. The rotating electric machine according to configuration 2, wherein the regulating portion includes a series diode connected in series to one of the first winding portion and the second winding portion. [Configuration 5] 5. The rotating electric machine according to any one of configurations 2 to 4, further comprising a parallel capacitor (110) that is a capacitor connected in parallel to the regulating portion. [Configuration 6] 6. The rotating electric machine according to configuration 5, further comprising a winding-side capacitor (120, 121) that is a capacitor connected in parallel to at least one of the first winding portion and the second winding portion. [Configuration 7] 5. The rotating electric machine according to any one of configurations 1 to 4, further comprising a winding-side capacitor (120, 121) connected in parallel to at least one of the first winding portion and the second winding portion. [Configuration 8] 8. The rotating electric machine according to claim 6 or 7, wherein the winding-side capacitor is connected in parallel to each of the first winding portion and the second winding portion. [Configuration 9] The rotating electric machine according to any one of configurations 1 to 8, wherein the electrical path is connected in parallel to one of the first winding portion and the second winding portion, which has weaker magnetic coupling with the stator winding. [Configuration 10] A rotating electric machine according to any one of configurations 1 to 8, wherein the electrical path is connected in parallel to one of the first winding portion and the second winding portion that is radially farther from the stator winding. [Configuration 11] A rotating electric machine as described in configuration 9, wherein the number of turns of the winding section that has weaker magnetic coupling with the stator winding, of the first winding section and the second winding section, is greater than the number of turns of the winding section that has stronger magnetic coupling. [Configuration 12] A rotating electric machine as described in configuration 10, wherein the number of turns of the winding section which is farther radially from the stator winding, of the first winding section and the second winding section, is greater than the number of turns of the winding section which is closer radially from the stator winding. [Configuration 13] A rotating electric machine according to any one of configurations 1 to 4, wherein the number of turns of the winding section, of the first winding section and the second winding section, to which the electrical paths are connected in parallel is greater than the number of turns of the winding section to which the electrical paths are not connected in parallel. [Explanation of symbols]

[0089] 40... rotating electric machine, 50... stator, 60... rotor, 70... field winding, 71... first winding portion, 72... second winding portion, 80... parallel diode.

Claims

1. a stator (50) having stator windings (52); a rotor (60) facing the stator in the radial direction; In a rotating electric machine (40) comprising: The rotor is a main pole portion (62) provided for each magnetic pole arranged in the circumferential direction and protruding in the radial direction; a field winding (70) wound around each of the main pole portions; and The field winding has a first winding portion (71) and a second winding portion (72), an electric path (80, 81) connected in parallel to at least one of the first winding portion and the second winding portion and configured to allow a current to flow in one direction through the electric path; a rotating electric machine, wherein the electrical path is connected in parallel to one of the first winding portion and the second winding portion, which has weaker magnetic coupling with the stator winding;

2. 2. The rotating electric machine according to claim 1, wherein the number of turns of one of the first winding portion and the second winding portion that has weaker magnetic coupling with the stator winding is greater than the number of turns of the other winding portion that has stronger magnetic coupling.

3. A stator (50) having a stator winding (52); a rotor (60) facing the stator in the radial direction; In a rotating electric machine (40) comprising: The rotor is a main pole portion (62) provided for each magnetic pole arranged in the circumferential direction and protruding in the radial direction; a field winding (70) wound around each of the main pole portions; and The field winding has a first winding portion (71) and a second winding portion (72), an electric path (80, 81) connected in parallel to at least one of the first winding portion and the second winding portion and configured to allow a current to flow in one direction through the electric path; a rotating electric machine, wherein the electrical path is connected in parallel to one of the first winding portion and the second winding portion that is farther away from the stator winding in the radial direction;

4. 4. The rotating electric machine according to claim 3, wherein the number of turns of the winding portion of the first winding portion or the second winding portion that is farther from the stator winding in the radial direction is greater than the number of turns of the winding portion that is closer to the stator winding in the radial direction.

5. The rotating electric machine according to any one of claims 1 to 4, further comprising a regulating section (90, 91) connected in series to one of the first winding section and the second winding section to which the electrical path is not connected in parallel, and causing current to flow in one direction.

6. The rotating electrical machine according to claim 5 , wherein the restricting portion is a series diode.

7. 5. The rotating electric machine according to claim 1, wherein a parallel diode is provided as the electrical path.

8. A stator (50) having a stator winding (52); a rotor (60) facing the stator in the radial direction; In a rotating electric machine (40) comprising: The rotor is a main pole portion (62) provided for each magnetic pole arranged in the circumferential direction and protruding in the radial direction; a field winding (70) wound around each of the main pole portions; and The field winding has a first winding portion (71) and a second winding portion (72), an electric path (80, 81) connected in parallel to one of the first winding portion and the second winding portion and configured to allow a current to flow in one direction through the electric path; a regulating section (90, 91) connected in series to one of the first winding section and the second winding section, the winding section to which the electrical path is not connected in parallel, and causing a current to flow in one direction; a parallel capacitor (110) connected in parallel to the restriction portion; winding-side capacitors (120, 121) that are capacitors connected in parallel to the first winding portion and the second winding portion, respectively; A rotating electric machine comprising:

9. The rotating electrical machine according to claim 8 , wherein the restricting portion is a series diode.

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