Rotary electric machine

Abstract

To provide a rotary electric machine that can reduce an eddy current loss generated in a holding member.SOLUTION: A rotary electric machine comprises: a stator having a stator winding; a rotor 60; a field magnet winding; and a holding member 90. The rotor 60 includes: a rotor core 61; and a main electrode part 62 projecting in a radial direction from the rotor core 61. The filed magnet winding is wound on the main electrode part 62. The holding member 90 is provided between the main electrodes 62 that are adjacent in a circumferential direction, and is attached to the rotor 60 and covers the field magnet winding from the stator side. The holding member 90 is formed of plate members made of a metal material stacked in an axis direction.SELECTED DRAWING: Figure 5

Description

[Technical Field]

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

[0002] Known rotating electric machines of this type include a stator having a stator winding, a rotor, and a field winding. The rotor has a rotor core and main poles provided for each of the circumferentially arranged magnetic poles and protruding radially from the rotor core toward the stator. A field winding is wound around each main pole.

[0003] The rotating electric machine includes a holding member that covers the field winding from the stator side and restricts radial movement of the field winding. Such a rotating electric machine is described in, for example, Patent Document 1. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-45956 Summary of the Invention [Problem to be solved by the invention]

[0005] When current flows through the stator winding, magnetic flux is generated. Some of the generated magnetic flux becomes leakage flux and interlinks with the holding member. If the holding member is made of a metal material such as aluminum, the magnetic flux interlinks with the holding member, causing eddy current loss.

[0006] A primary object of the present disclosure is to provide a rotating electric machine capable of reducing eddy current loss occurring in a holding member. [Means for solving the problem]

[0007] The present disclosure provides a motor comprising: a stator having stator windings; a rotor having a rotor core and main pole portions provided for the magnetic poles arranged in the circumferential direction and protruding radially from the rotor core toward the stator; a field winding wound around each of the main pole portions; a holding member provided between the main pole portions adjacent in the circumferential direction and attached to the rotor, the holding member covering the field winding from the stator side; Equipped with The holding member is configured by stacking plate-shaped members made of a metal material in the axial direction.

[0008] A holding member having a laminated structure of plate-like members can increase the electrical resistance between the layers of the plate-like members, and can reduce eddy current loss occurring in the holding member. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is an overall configuration diagram of a control system for a rotating electrical machine according to a first embodiment; [Figure 2] FIG. 2 is a diagram showing an inverter and its peripheral configuration. [Figure 3] FIG. [Figure 4] FIG. 3 is a diagram showing an electric circuit provided in the rotor. [Figure 5] Cross-sectional view of the rotor. [Figure 6] FIG. [Figure 7] FIG. 10 is a perspective view showing an example of a welding point of a holding member. [Figure 8] FIG. 10 shows the calculation results of eddy current loss generated in the outer and inner plate sections. [Figure 9] FIG. 10 is a cross-sectional view of a rotor according to a second embodiment. [Figure 10] FIG. 10 is a cross-sectional view of a rotor according to a third embodiment. [Figure 11] FIG. [Figure 12] FIG. 10 is a cross-sectional view of a rotor according to a fourth embodiment. [Figure 13] Cross-sectional view of the rotor. [Figure 14]FIG. [Figure 15] FIG. 11 is a plan view showing a main pole according to a modification of the fourth embodiment, developed in the circumferential direction. [Figure 16] FIG. 10 is a cross-sectional view of a rotor according to a fifth embodiment. [Figure 17] FIG. [Figure 18] FIG. 4 is a perspective view showing a manner in which a non-magnetic member is fixed to a main pole portion. [Figure 19] FIG. 13 is a plan view showing a main pole according to a modification of the fifth embodiment, developed in the circumferential direction. [Figure 20] FIG. 13 is a perspective view of a non-magnetic member according to a modified example of the fifth embodiment. [Figure 21] FIG. 10 is a cross-sectional view of a rotor according to a sixth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Several embodiments will be described with reference to the drawings. In several embodiments, functionally and / or structurally corresponding and / or associated parts may be assigned the same reference numerals or reference numerals that differ in the hundredth or more digit. For corresponding and / or associated parts, reference may be made to the descriptions of other embodiments.

[0011] 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 constitute 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.

[0012] 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 form an electromechanical integrated drive device, or the rotating electric machine 40, the inverter 20, and the control device 30 may each be formed by a separate component.

[0013] 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.

[0014] The stator 50 includes a stator core 51 and a stator winding 52. The stator winding 52 is made of, for example, copper wire, and includes U-, V-, and W-phase windings 52U, 52V, and 52W that are arranged with an electrical angle offset of 120° from one another.

[0015] 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 assembling the field winding 70. The field winding 70 may be formed of, for example, aluminum wire. Aluminum wire has a low specific gravity and can reduce the centrifugal force when the rotor 60 rotates. Aluminum wire has lower strength and hardness than copper wire, making it suitable for compression molding. The field winding 70 is not limited to aluminum wire, and may be, for example, copper wire or CNT (carbon nanotube). The field winding 70 does not have to be formed by compression molding.

[0016] A rotary shaft 32 is inserted through the central hole of the rotor core 61. The rotary shaft 32 is rotatably supported by the housing 41 via a bearing .

[0017] 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 U-, V-, and W-phase windings 52U, 52V, and 52W are connected to the connection points between 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 to the neutral point. That is, in this embodiment, the U-, V-, and W-phase windings 52U, 52V, and 52W are star-connected. Note that, 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.

[0018] 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.

[0019] Next, the stator 50 and the rotor 60 will be described with reference to FIG.

[0020] The stator 50 and the rotor 60 are both arranged coaxially (specifically, on the central axis of rotation O) 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.

[0021] The stator 50 is made of laminated steel plates made of a soft magnetic material and has an annular back yoke 51a and multiple teeth 51b protruding radially inward from the back yoke 51a. Multiple slots 54 are formed between adjacent teeth 51b 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. For example, the stator 50 may have a segment coil structure using multiple conductor segments. However, the structure of the stator winding 52 is arbitrary.

[0022] 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 that protrude radially outward from the rotor core 61. In this embodiment, eight main poles 62 are provided at equal intervals in the circumferential direction. The main poles 62 extend in the axial direction.

[0023] 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 relative to 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. Furthermore, of circumferentially adjacent main pole portions 62, the winding directions of the winding portions 71a, 71b wound around one are opposite to the winding directions of the winding portions 71a, 71b wound around the other. Therefore, the magnetization directions of circumferentially adjacent main pole portions 62 are opposite to each other.

[0024] FIG. 4 shows an electrical circuit on the rotor 60 side, which includes the windings 71a and 71b wound around the common main pole 62. The rotor 60 is provided with a diode 80 as a rectifying element and a capacitor 81. The diode 80 is electrically connected in parallel to the series connection of the first winding 71a and the second winding 71b. More specifically, a first end of the first winding 71a is connected to the cathode of the diode 80, and a first end of the second winding 71b is connected to the second end of the first winding 71a. An anode of the diode 80 is connected to the second end of the second winding 71b. A capacitor 81 is electrically connected in parallel to the second winding 71b. In FIG. 4, L1 represents the inductance of the first winding 71a, L2 represents the inductance of the second winding 71b, and C represents the capacitance of the capacitor 81.

[0025] In this embodiment, a series resonant circuit is configured including the first winding portion 71a, the capacitor 81, and the diode 80, and a parallel resonant circuit is configured including the second winding portion 71b and the capacitor 81. 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.

[0026] 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.

[0027] Returning to the explanation of FIG. 2, the control device 30 is an electronic control unit (EC) mainly composed of a microcomputer 31. The microcomputer 31 includes a CPU (Central Processing Unit). The control device 30 generates drive signals that turn on and off each of the switches SUp to SWn that constitute the inverter 20. More specifically, the control device 30 converts DC power output from the DC power supply 10 into AC power and supplies the AC power to the U-, V-, and W-phase windings 52U, 52V, and 52W by generating drive signals that turn on and off each of the arm switches SUp to SWn, and supplies the generated drive signals to the gates of the arm switches SUp to SWn.

[0028] The control device 30 turns on and off each of the switches SUp to SWn so that a composite current of fundamental current and harmonic current flows through each of the phase windings 52U, 52V, 52W. The fundamental current is a current that mainly generates torque in the rotary electric machine 40. The harmonic current is a current that mainly excites the field winding 70 and induces a field current in the field winding 70. By performing switching control of the inverter 20, a composite current in which harmonic current is superimposed on the fundamental current flows through each of the phase windings 52U, 52V, 52W. The phase currents flowing through each of the phase windings 52U, 52V, 52W are shifted by 120 electrical degrees.

[0029] 3, 5, and 6, the holding member 90 attached to the rotor 60 will be described. The holding member 90 is a member for restricting radial movement of the field winding 70 even when centrifugal force acts on the field winding 70 as the rotor 60 rotates. The holding member 90 is made of a non-magnetic metal material, such as aluminum or austenitic stainless steel (e.g., SUS). The reason for using a non-magnetic material is to avoid affecting the magnetic circuit including the rotor 60 and the stator 50.

[0030] The holding member 90 includes an outer plate portion 100 (corresponding to the "first plate portion"), an inner plate portion 110 (corresponding to the "second plate portion"), and a connecting portion 120. The outer plate portion 100 is provided at a radially outer position of the first winding portion 71a so as to bridge between circumferentially adjacent main pole portions 62. The outer plate portion 100 is shaped like a circular arc extending circumferentially so as to be convex radially outward, and is also shaped like a plate extending axially. The first winding portion 71a is covered by the outer plate portion 100.

[0031] The inner plate portion 110 is disposed radially between the first winding portion 71a and the second winding portion 71b, spanning between the main pole portions 62 adjacent in the circumferential direction. The inner plate portion 110 is shaped like a circular arc extending in the circumferential direction so as to protrude radially outward, and is also shaped like a plate extending in the axial direction. The second winding portion 71b is covered by the inner plate portion 110. The circumferential length of the inner plate portion 110 is smaller than the circumferential length of the outer plate portion 100.

[0032] The connecting portion 120 is provided between the first winding portions 71a adjacent in the circumferential direction and extends in the radial direction. The connecting portion 120 connects the circumferential center of the outer plate portion 100 and the circumferential center of the inner plate portion 110.

[0033] Next, a configuration for fixing the holding member 90 to the main pole portion 62 will be described. A first protrusion 101 extending in the circumferential direction is provided on the radially inner portions of both circumferential end portions of the outer plate portion 100. As shown in FIG. 6, the first protrusion 101 extends from one end to the other end in the axial direction of the outer plate portion 100. A second protrusion 111 extending in the circumferential direction is provided on the radially inner portions of both circumferential end portions of the inner plate portion 110. The second protrusion 111 extends from one end to the other end in the axial direction of the inner plate portion 110.

[0034] A first recess 63 that is recessed in the circumferential direction and extends in the axial direction is formed at both circumferential ends of the tip of the main pole 62. A second recess 64 that is recessed in the circumferential direction and extends in the axial direction is formed at both circumferential ends of an axially intermediate portion of the main pole 62. The second recess 64 is formed in a portion of the main pole 62 between the first winding portion 71a and the second winding portion 71b in the axial direction.

[0035] By moving the holding member 90 relative to the rotor 60 in the axial direction, the first protrusion 101 of the outer plate portion 100 is fitted into the first recess 63 of the main pole portion 62, and the second protrusion 111 of the inner plate portion 110 is fitted into the second recess 64 of the main pole portion 62. This fixes the holding member 90 to the main pole portion 62.

[0036] 6, the holding member 90 is configured by stacking a plurality of plate-shaped members 91 made of a non-magnetic metal material in the axial direction. An insulating layer (e.g., an insulating coating) having electrical insulation properties is formed on the surface of the plate-shaped members 91. The stacked structure of the plate-shaped members 91 is intended to reduce eddy current loss generated in the holding member 90.

[0037] That is, magnetic flux is generated when current is applied to the stator winding 52. A part of the generated magnetic flux becomes leakage flux and interlinks with the holding member 90. As a result, eddy current loss occurs in the holding member 90. The holding member 90 has a laminated structure of plate-like members 91, which can increase the electrical resistance between the layers and reduce the eddy current loss generated in the holding member 90.

[0038] Furthermore, of the plate-like members 91 constituting the holding member 90, at least one of the inner plate portion 110 and the connecting portion 120 is welded or crimped to integrate the plate-like members 91, thereby forming the holding member 90. Of the plate-like members 91 constituting the holding member 90, the outer plate portion 100 does not have any welded or crimped fixing points. This can enhance the effect of reducing eddy current loss.

[0039] 8 shows the calculation results of the eddy current loss occurring in the outer plate portion 100 and the inner plate portion 110. As shown in Fig. 8, the eddy current loss in the outer plate portion 100, which is relatively close to the stator winding 52, is significantly larger than the eddy current loss in the inner plate portion 110, which is relatively far from the stator winding 52.

[0040] When multiple plate-shaped members 91 are integrated by welding or crimping, for example, the insulating layer formed on the surface of each plate-shaped member 91 may peel off, resulting in electrical connection of at least some of the welded or crimped portions of each plate-shaped member 91. In this case, the effect of reducing eddy current loss is reduced. Therefore, by welding or crimping the inner plate portion 110 and the connecting portion 120, which have relatively small eddy current loss, the effect of reducing eddy current loss is enhanced.

[0041] Fig. 7 shows an example in which the inner plate portion 110 of each plate-like member 91 is welded at a plurality of locations. The welded welds 130 extend from one end to the other in the axial direction of the outer plate portion 100. In the example shown in Fig. 7, the welds 130 are located near the connection point with the connecting portion 120, at the radially outer portions of both circumferential ends of the inner plate portion 110, and at the radially inner portion.

[0042] It is noted that only the inner plate portion 110 and the connecting portion 120 of each plate-like member 91 may be welded or crimped, or only the connecting portion 120 may be welded or crimped. When crimping is used, the crimped portions of the plate-like members 91 may be compressed in the stacking direction of the plate-like members 91 to plastically deform them, thereby integrating the plate-like members 91.

[0043] In this embodiment, in order to pass a field current through the field winding 70 without using brushes, a harmonic current is superimposed on the current passed through the stator winding 52. In this case, when current is passed through the stator winding 52, further harmonic magnetic flux is generated, and some of the generated harmonic magnetic flux becomes leakage flux and interlinks with the holding member 90. For this reason, in a configuration in which a harmonic current is superimposed on the current passed through the stator winding 52, eddy current loss in the holding member 90 is likely to increase. In such a configuration, the use of a holding member 90 having a laminated structure offers significant advantages.

[0044] <Modification of the first embodiment> Of the plate-like members 91 constituting the holding member 90, the outer plate portions 100 may be fixed by welding or crimping to integrate the plate-like members 91. Even in this case, the effect of reducing eddy current loss can be obtained.

[0045] Each plate-like member 91 may be fixed with an adhesive instead of being fixed by welding or crimping.

[0046] 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. 9, a flange 65 extending on both sides in the circumferential direction is provided at the tip of each main pole 62. The radially inner portion of the circumferential tip of the flange 65 is formed as a recess 66 recessed in the circumferential direction.

[0047] The retaining member 90 is arranged so that the first protrusions 101 of the outer plate portion 100 come into contact with the recesses 66 of the flange portion 65 by moving the retaining member 90 in the axial direction relative to the rotor 60. This causes the circumferential tip end of the flange portion 65 and the first protrusions 101 of the outer plate portion 100 to overlap in the radial direction. As a result, when centrifugal force generated as the rotor 60 rotates acts on the retaining member 90, both circumferential ends of the outer plate portion 100 can be supported by the circumferential tip end of the flange portion 65.

[0048] Furthermore, the structure in which both circumferential ends of the outer plate portion 100 are supported by the circumferential ends of the flange portion 65 can be realized without increasing the radial dimensions of the flange portion 65 and the outer plate portion 100. This makes it possible to expand the winding space surrounded by circumferentially adjacent main pole portions 62 and outer plate portions 100.

[0049] <Modification of the second embodiment> The recess 66 may not be provided in the radially outer portion of the circumferential tip of the flange 65. In this case, the first protrusions 101 may not be provided at both circumferential ends of the outer plate portion 100.

[0050] Third Embodiment The third embodiment will be described below with reference to the drawings, focusing on differences from the first embodiment. In this embodiment, as shown in FIG. 10, the radially outer portion of the main pole portion 162 is an expanded diameter portion 170a, and the radially inner portion is a reduced diameter portion 170b. The circumferential length of the reduced diameter portion 170b is smaller than the circumferential length of the expanded diameter portion 170a. This allows for a larger installation space for the second winding portion 71b. As a result, the number of turns of the second winding portion 71b can be increased, and the cross-sectional area of ​​the second winding portion 71b can be increased.

[0051] As in the second embodiment, a flange 165 and a recess 166 are provided at the tip of the expanded diameter portion 170a.

[0052] The boundary between the expanded diameter portion 170a and the reduced diameter portion 170b is a stepped portion 167. As shown in FIG. 11 , the retaining member 90 of this embodiment does not have a second protrusion 111 provided on the inner plate portion 110. Both circumferential ends of the inner plate portion 110 abut against the stepped portion 167. As a result, the inner plate portion 110 is supported by the stepped portion 167.

[0053] The main pole portion 162 is a split core that can be attached to and detached from the rotor core 61. A protrusion 168 that protrudes radially is provided at the base end of the reduced diameter portion 170b that constitutes the main pole portion 162. The protrusion 168 has a wedge shape with a circumferential dimension that increases radially inward. Grooves 61a are formed at predetermined intervals in the circumferential direction in the radially outer portion of the rotor core 61. The grooves 61a open radially outward, and the circumferential groove width increases radially inward. The protrusions 168 are fitted into the grooves 61a.

[0054] The main pole portion 162, around which the first winding portion 71a and the second winding portion 71b are wound, is moved axially relative to the rotor core 61, so that the protrusion 168 of the main pole portion 162 fits into the groove 61a of the rotor core 61. This fixes the main pole portion 162 to the rotor core 61. Thereafter, the holding member 90 is moved axially relative to the rotor 60, so that the holding member 90 is fixed to the main pole portion 162.

[0055] <Fourth embodiment> The fourth embodiment will be described below with reference to the drawings, focusing on differences from the second embodiment. In this embodiment, a skew structure is employed in the rotor 60 as shown in FIGS. 12 to 14 in order to reduce torque ripple in the rotating electrical machine 40. FIG. 14 is a plan view of the tip end of the main pole developed in the circumferential direction. FIG. 12 is a cross-sectional view of the rotor 60 corresponding to line 12-12 in FIG. 14, and FIG. 13 is a cross-sectional view of the rotor 60 corresponding to line 13-13 in FIG. 13.

[0056] Of the main pole parts extending in the axial direction, the part on one side of the axial center position is the first main pole part 262A shown in Fig. 12, and the part on the other side is the second main pole part 262B shown in Fig. 13. The dashed dotted line in Fig. 14 indicates an imaginary plane extending in the radial direction and passing through the rotation center O (see Fig. 3) of the rotating shaft 32.

[0057] 12, the tip end of the first main pole portion 262A is provided with a first long-side flange 265A extending circumferentially in a first direction, and a first short-side flange 266A extending circumferentially in a second direction opposite to the first direction. The circumferential length of the first long-side flange 265A is greater than the circumferential length of the first short-side flange 266A.

[0058] The radially inner portion of the circumferential tip of the first long side flange 265A is recessed in the circumferential direction to form a first long side recess 267A. The radially inner portion of the circumferential tip of the first short side flange 266A is recessed in the circumferential direction to form a first short side recess 268A. As in the second embodiment, the first protrusion 101 of the outer plate portion 100 abuts against the first long side protrusion 267A and the first short side protrusion 268A.

[0059] 13, a second short-side flange 265B extending circumferentially in a first direction and a second long-side flange 266B extending circumferentially in a second direction are provided at the tip of the second main pole portion 262B. The circumferential length of the second short-side flange 265B is shorter than the circumferential length of the second long-side flange 266B. In this embodiment, the circumferential length of the second short-side flange 265B is the same as the circumferential length of the first short-side flange 266A, and the circumferential length of the second long-side flange 266B is the same as the circumferential length of the first long-side flange 265A.

[0060] The radially inner portion of the circumferential tip of the second short side flange 265B is formed as a second short side recess 267B that is recessed in the circumferential direction. The radially inner portion of the circumferential tip of the second long side flange 266B is formed as a second long side recess 268B that is recessed in the circumferential direction. As in the second embodiment, the first protrusion 101 of the outer plate portion 100 abuts against the second short side recess 267B and the second long side recess 268B. Note that in this embodiment, the holding member 90 fixed to the second main pole portion 262B and the holding member 90 fixed to the first main pole portion 262A are separate members.

[0061] As shown in FIG. 14, the amount of circumferential deviation between the circumferential tip of the first long-side flange 265A constituting the first main pole portion 262A and the circumferential tip of the second short-side flange 265B constituting the second main pole portion 262B is θnt. The amount of circumferential deviation between the circumferential tip of the first short-side flange 266A constituting the first main pole portion 262A and the circumferential tip of the second long-side flange 266B constituting the second main pole portion 262B is also θnt. In this case, when one slot pitch of the stator 50 is β (see FIG. 3), the relationship "1 / 3 × β < θnt < 2 / 3 × β" is satisfied. This allows torque ripple to be reduced. In particular, in this embodiment, "θnt = β / 2" is satisfied. This enhances the torque ripple reduction effect.

[0062] In this embodiment, the axial length La of the first main pole portion 262A is equal to the axial length La of the second main pole portion 262B, which can further enhance the effect of reducing torque ripple.

[0063] <Modification of the Fourth Embodiment> As shown in Fig. 15, the first main pole portions 262A and the second main pole portions 262B may be arranged alternately in the axial direction. In this case, it is sufficient that the total axial length (= Lb / 2 + Lb + Lb + Lb / 2) of the first main pole portions 262A (first long-side flange portion 265A, first short-side flange portion 266A) is equal to the total axial length (= Lb + Lb + Lb) of the second main pole portions 262B (second short-side flange portion 265B, second long-side flange portion 266B). In the example shown in Fig. 15, the first main pole portions 262A and the second main pole portions 262B are arranged so that the main pole portion consisting of the main pole portions 262A and 262B is line-symmetrical with respect to the center in the axial direction of the main pole portion. This can enhance the torque ripple reduction effect.

[0064] Fifth Embodiment The fifth embodiment will be described below with reference to the drawings, focusing on differences from the first embodiment. In this embodiment, as shown in Fig. 16, a notch 300 extending in the axial direction is formed at one circumferential end of the tip of the main pole portion 62. The notch 300 is open in both the radial and circumferential directions. If the one slot pitch of the stator 50 is β (see Fig. 3) and the circumferential width of the notch 300 is θnt, then "1 / 3 × β < θnt < 2 / 3 × β" is satisfied, and more specifically, "θnt = β / 2" is satisfied. This reduces the torque ripple of the rotating electric machine 40.

[0065] If a notch 300 is provided at the tip of the main pole 62, the support portion at the circumferential end of the outer plate 100 will be lost. Therefore, in this embodiment, as shown in Figures 16 to 18, a non-magnetic member 400 (corresponding to a "non-magnetic portion") made of a non-magnetic synthetic resin is provided in the missing portion of the tip of the main pole 62 caused by the notch 300. The non-magnetic member 400 extends in the axial direction. The circumferential width of the non-magnetic member 400 is θnt, the same as the circumferential width of the notch 300. Since the non-magnetic member 400 that fills the missing portion is made of a non-magnetic material, a torque ripple reduction effect can be obtained.

[0066] The non-magnetic member 400 is provided with a non-magnetic recess 401 recessed in the circumferential direction. The first protrusion 101 of the outer plate portion 100 is fitted into the non-magnetic recess 401. This allows both circumferential ends of the outer plate portion 100 to be supported.

[0067] An example of a method for fixing the non-magnetic member 400 to the main pole 62 will be described with reference to FIGS.

[0068] Axial projections 402 are provided at both axial ends of the non-magnetic member 400. Circumferentially recessed grooves 301 are provided at both axial ends of the tip of the main pole 62. By moving the non-magnetic member 400 circumferentially relative to the main pole 62, the projections 402 of the non-magnetic member 400 are fitted into the grooves 301 of the main pole 62. This fixes the non-magnetic member 400 to the main pole 62.

[0069] Note that a guide recess 302 recessed in the circumferential direction is provided in a portion of the tip of the main pole 62 radially outward of the groove 301. When the non-magnetic member 400 is fixed to the missing portion defined by the notch 300, the non-magnetic recess 401 and the guide recess 302 are connected in the axial direction. As a result, when the non-magnetic member 400 is fixed to the missing portion defined by the notch 300, the circumferential end of the outer plate portion 100 constituting the holding member 90 can be moved axially and fitted into the non-magnetic recess 401 via the guide recess 302.

[0070] <Modification of the Fifth Embodiment> The non-magnetic member 400 may be made of a material other than synthetic resin, as long as it is a non-magnetic material.

[0071] As shown in Fig. 19, a notch may be formed at each of both circumferential ends of the tip of each main pole 62. Fig. 19 is a plan view of the tip of the main pole 62 developed in the circumferential direction.

[0072] One of the two circumferential ends of the main pole portion 62 is referred to as a first main pole end portion 362A, and the other is referred to as a second main pole end portion 362B. A first notch 310A extending in the axial direction is formed in a part of the first main pole end portion 362A, and a second notch 310B extending in the axial direction is formed in a part of the second main pole end portion 362B.

[0073] A plurality of first notches 310A (three are shown in this example) are formed in the first main pole end 362A and spaced apart from each other in the axial direction. A plurality of second notches 310B (three are shown in this example) are formed in the second main pole end 362B and spaced apart from each other in the axial direction. The first notches 310A and the second notches 310B are formed in positions that do not overlap in the axial direction. The width dimensions in the circumferential direction of the first notches 310A and the second notches 310B are the same, θnt. It is set to "1 / 3 × β<θnt<2 / 3 × β", and specifically "θnt = β / 2".

[0074] Figure 20 shows a non-magnetic member 500 of this embodiment. Similar to the non-magnetic member 400 of Figure 17, the non-magnetic member 500 is provided with a non-magnetic recess 501 and a protrusion 502. The non-magnetic member 500 is fixed to each of the cutouts 310A, 310B. Similar to the configuration of Figure 18, the first and second main pole ends 362A, 362B are provided with first and second guide recesses 372A, 372B into which the circumferential ends of the inner plate portion 110 are fitted.

[0075] 19, the total axial length (=Lc+Lc+Lc) of the portion (non-magnetic member 500) where the first notch 310A is formed in the first main pole end 362A is equal to the total axial length (=Lc+Lc+Lc) of the portion (non-magnetic member 500) where the second notch 310B is formed in the second main pole end 362B. This enhances the torque ripple reduction effect.

[0076] Sixth Embodiment The sixth embodiment will be described below with reference to the drawings, focusing on differences from the fifth embodiment. In this embodiment, as shown in FIG. 21 , a first insulating member 600 is provided between the first winding portion 71a and the connecting portion 120 of the holding member 90. A second insulating member 601 is provided between the second winding portion 71b and the second winding portion 71b of the adjacent pole. The first insulating member 600 and the second insulating member 601 are made of a non-magnetic material with electrical insulation properties, such as synthetic resin. The first insulating member 600 is wedge-shaped and functions as a wedge between the first winding portion 71a and the connecting portion 120. The second insulating member 601 is wedge-shaped and functions as a wedge between the second winding portion 71b and the second winding portion 71b of the adjacent pole.

[0077] According to the present embodiment described above, the field winding 70 can be firmly fixed, and the resistance of the rotary electric machine 40 to centrifugal force and vibration can be increased.

[0078] <Other embodiments> The above-described embodiments may be modified as follows.

[0079] The configuration of the sixth embodiment may be applied to the first to fourth embodiments.

[0080] The capacitor 81 that constitutes the resonant circuit may be electrically connected in parallel to the first winding portion 71a instead of the second winding portion 71b.

[0081] The holding member 90 does not have to be provided with the connecting portion 120. In other words, in this case, it is sufficient that the holding member 90 includes two members: an outer plate member corresponding to the outer plate portion 100, and an inner plate member corresponding to the inner plate portion 110. Furthermore, the holding member 90 does not have to be provided with the connecting portion 120 and the inner plate portion 110. In other words, in this case, it is sufficient that the holding member 90 includes the outer plate member.

[0082] 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 poles protrude radially inward from the rotor core. Even in an outer rotor type rotating electric machine, a retaining member may be provided that covers the field winding from the radially inner side to prevent the field winding from being exposed between circumferentially adjacent main poles.

[0083] The rotating electric machine is not limited to a star-connected rotating electric machine, but may be a delta-connected rotating electric machine.

[0084] The stator core may not have teeth.

[0085] The configuration for passing a field current through the field winding is not limited to the circuit shown in Fig. 4, and may include, for example, a configuration including brushes electrically connected to the field winding and a power supply electrically connected to the brushes. In this case, it is not necessary to apply a harmonic voltage to the stator winding to induce a field current.

[0086] The rotating electric machine is not limited to a rotating electric machine used as an in-vehicle main engine, but may also be, for example, a rotating electric machine used as an ISG (Integrated Starter Generator) which is a motor and generator.

[0087] The mobile 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 mobile body, but may be a stationary system. [Explanation of symbols]

[0088] 40... rotating electric machine, 50... stator, 52... stator winding, 60... rotor, 70... field winding, 90... holding member.

Claims

1. a stator (50) having stator windings (52); a rotor (60) having a rotor core (61) and main pole portions (62, 162, 262A, 262B) provided for each of the magnetic poles arranged in a circumferential direction and protruding radially from the rotor core toward the stator; A field winding (70) wound around each of the main pole portions; a retaining member (90) provided between the main pole portions adjacent to each other in the circumferential direction and attached to the rotor, the retaining member covering the field winding from the stator side; Equipped with The retaining member is configured by stacking plate-like members (91) made of a metal material in the axial direction.

2. The field winding has a first winding portion (71a) and a second winding portion (71b) electrically connected in series, the first winding portion is disposed closer to the stator than the second winding portion in a radial direction, The holding member is a first plate portion (100) provided on the stator side with respect to the first winding portion in the radial direction and covering the first winding portion from the stator side; a second plate portion (110) provided between the first winding portion and the second winding portion in the radial direction and covering the second winding portion from the stator side; a connecting portion (120) provided between adjacent first winding portions in the circumferential direction and extending in the radial direction to connect the first plate portion and the second plate portion; having The rotating electric machine according to claim 1 , wherein at least one of the second plate portion and the connecting portion of each of the plate-like members constituting the retaining member is welded or crimped to integrate the plate-like members.

3. 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 A notch (300, 310A, 310B) extending in the axial direction is formed in at least one of both circumferential ends of the tip of the main pole portion (62), When one slot pitch of the stator is β and the width of the notch in the circumferential direction is θnt, “1 / 3×β<θnt<2 / 3×β”, a non-magnetic portion (400, 500) made of a non-magnetic material is provided in a portion of the main pole that is missing due to the notch, 3. The rotating electric machine according to claim 2, wherein the circumferential end of the tip of the main pole portion and the non-magnetic portion are provided with a recess (401, 501) that is recessed in the circumferential direction and into which the circumferential end of the first plate portion is fitted.

4. The rotating electric machine according to claim 3 , wherein θnt=β / 2.

5. A flange portion (65) extending on both sides in the circumferential direction is provided at the tip portion of the main pole portion (62), A portion of a circumferential tip of the flange portion on the rotor core side in the radial direction is a recess (66) recessed in the circumferential direction, A protrusion (101) extending in the circumferential direction is provided on a portion of each of both circumferential end portions of the first plate portion that is radially adjacent to the rotor core, The rotating electric machine according to claim 2 , wherein the retaining member is provided such that the protrusion abuts against the recess and a circumferential tip of the flange and the protrusion overlap in the radial direction.

6. The main pole portion has a first main pole portion (262A) and a second main pole portion (262B), A first long side flange portion (265A) extending in a first direction in the circumferential direction and a first short side flange portion (266A) extending in a second direction opposite to the first direction in the circumferential direction are provided at a tip end portion of the first main pole portion, The circumferential length dimension of the first long side flange portion is greater than the circumferential length dimension of the first short side flange portion, A tip end portion of the second main pole portion is provided with a second short side flange portion (265B) extending circumferentially toward the first direction side and a second long side flange portion (266B) extending circumferentially toward the second direction side, The circumferential length dimension of the second short side flange portion is shorter than the circumferential length dimension of the second long side flange portion, 3. The rotating electric machine of claim 2, wherein, when a circumferential deviation between the circumferential tip of the first long side flange and the circumferential tip of the second short side flange is θnt, a circumferential deviation between the circumferential tip of the first short side flange and the circumferential tip of the second long side flange is θnt, and one slot pitch of the stator is β, then "1 / 3 x β < θnt < 2 / 3 x β" is satisfied.

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

8. In the main pole portion (162), a circumferential length dimension of a reduced diameter portion (170b) which is a portion on the rotor core side in the radial direction is smaller than a circumferential length dimension of an expanded diameter portion (170a) which is a portion on the stator side in the radial direction, 3. The rotating electric machine according to claim 2, wherein both circumferential ends of the second plate portion are supported by a step portion between the enlarged diameter portion and the reduced diameter portion.

9. 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 (81) electrically connected in parallel to either the first winding portion or the second winding portion; having 9. The rotating electric machine according to claim 2, wherein a harmonic current for inducing a field current in said field winding flows in said stator winding.

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