Rotating 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

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[0001] The present disclosure relates to a wound-field type rotating electrical machine.

Background Art

[0002] As this type of rotating electrical machine, one having a stator with stator windings, a rotor, and field windings is known. The rotor has a rotor core and main pole portions provided for each of the magnetic poles arranged in the circumferential direction and protruding radially from the rotor core toward the stator side. The field windings are wound around each main pole portion.

[0003] The rotating electrical machine includes a holding member. The holding member covers the field windings from the stator side and restricts the movement of the field windings in the radial direction. Such a rotating electrical machine is described in, for example, Patent Document 1.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] When an electric current is applied to the stator windings, magnetic flux is generated. A part of the generated magnetic flux becomes leakage magnetic flux and intersects with the holding member. When the holding member is made of a metal material such as aluminum, eddy current loss occurs due to the intersection of magnetic flux with the holding member.

[0006] A main object of the present disclosure is to provide a rotating electrical machine capable of reducing eddy current loss generated in the holding member.

Means for Solving the Problems

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

[0008] A holding member for a laminated structure of plate-like members can increase the electrical resistance between layers of the plate-like members and reduce eddy current losses generated in the holding member. [Brief explanation of the drawing]

[0009] [Figure 1] Overall configuration diagram of the control system for a rotating electric machine according to the first embodiment. [Figure 2] A diagram showing the inverter and its peripheral components. [Figure 3] Cross-sectional view of the rotor and stator. [Figure 4] A diagram showing the electrical circuitry of the rotor. [Figure 5] Cross-sectional view of the rotor. [Figure 6] Perspective view of the retaining member. [Figure 7] A perspective view showing an example of a welding location on a retaining member. [Figure 8] This figure shows the calculation results of eddy current losses occurring in the outer and inner plate sections. [Figure 9] A cross-sectional view of the rotor according to the second embodiment. [Figure 10] A cross-sectional view of the rotor according to the third embodiment. [Figure 11] Perspective view of the retaining member. [Figure 12] A cross-sectional view of the rotor according to the fourth embodiment. [Figure 13] Cross-sectional view of the rotor. [Figure 14]Plan view of the main pole part developed in the circumferential direction. [Figure 15] Plan view of the main pole part according to a modification of the fourth embodiment, developed in the circumferential direction. [Figure 16] Cross-sectional view of the rotor according to the fifth embodiment. [Figure 17] Perspective view of the non-magnetic member. [Figure 18] Perspective view showing the fixing mode of the non-magnetic member to the main pole part. [Figure 19] Plan view of the main pole part according to a modification of the fifth embodiment, developed in the circumferential direction. [Figure 20] Perspective view of the non-magnetic member according to a modification of the fifth embodiment. [Figure 21] Cross-sectional view of the rotor according to the sixth embodiment.

Mode for Carrying Out the Invention

[0010] A plurality of embodiments will be described while referring to the drawings. In the plurality of embodiments, parts that are functionally and / or structurally corresponding and / or associated may be assigned the same reference numerals, or reference numerals with a difference in the hundreds or more digits. For corresponding parts and / or associated parts, the descriptions of other embodiments can be referred to.

[0011] <First Embodiment> Hereinafter, a first embodiment in which a rotating electrical machine and a control device for the rotating electrical machine according to the present disclosure are embodied will be described while referring to the drawings. The rotating electrical machine and the control device constitute a control system for the rotating electrical machine, and the control system is mounted on a vehicle. The rotating electrical machine is a driving power source for the vehicle.

[0012] As shown in FIG. 1, the control system includes a DC power supply 10, an inverter 20, a control device 30, and a rotating electrical machine 40. The rotating electrical machine 40 is a field winding type synchronous machine. For example, an electromechanical integrated drive device is constituted by including the rotating electrical machine 40, the inverter 20, and the control device 30, or each of the rotating electrical machine 40, the inverter 20, and the control device 30 is constituted by each component.

[0013] The rotating electric machine 40 comprises a housing 41 and a stator 50 and a rotor 60 housed within the housing 41. The rotating electric machine 40 in this embodiment is an inner rotor type rotating electric machine in which the rotor 60 is positioned radially inward of the stator 50.

[0014] The stator 50 comprises a stator core 51 and stator windings 52. The stator windings 52 are made of, for example, copper wire and include U, V, and W phase windings 52U, 52V, and 52W arranged at an electrical angle of 120° from each other.

[0015] The rotor 60 comprises a rotor core 61 and a field winding 70. The field winding 70 is constructed, for example, by compression molding. This improves the space utilization ratio and the ease of assembly of the field winding 70. The field winding 70 may be made of, for example, aluminum wire. Aluminum wire has a low specific gravity, which 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. Furthermore, the field winding 70 is not limited to aluminum wire; for example, it may be made of copper wire or CNT (carbon nanotube). Also, the field winding 70 does not have to be made by compression molding.

[0016] A rotating shaft 32 is inserted through the central hole of the rotor core 61. The rotating shaft 32 is rotatably supported in the housing 41 via a bearing 42.

[0017] As shown in Figure 2, the inverter 20 comprises a series connection of U, V, W phase upper arm switches Sup, SVp, SWp and U, V, W phase lower arm switches SUn, SVn, SWn. The first ends of the U, V, W phase windings 52U, 52V, 52W are connected to the connection points between the U, V, W phase upper arm switches Sup, SVp, SWp and the U, V, W phase lower arm switches SUn, SVn, SWn. The second ends of the U, V, W phase windings 52U, 52V, 52W are connected at the neutral point. In other words, in this embodiment, the U, V, W phase windings 52U, 52V, 52W are star-connected. In this embodiment, each switch Sup to SWn is an IGBT. A freewheeling diode is connected in antiparallel to each switch Sup to SWn.

[0018] The collectors of the U, V, W phase upper arm switches Sup, SVp, and SWp are connected to the positive terminals of the DC power supply 10. The emitters of the U, V, W phase lower arm switches SUn, SVn, and SWn are connected to the negative terminals of the DC power supply 10. A smoothing capacitor 11 is connected in parallel to the DC power supply 10.

[0019] Next, we will explain the stator 50 and rotor 60 using Figure 3.

[0020] The stator 50 and rotor 60 are both arranged coaxially with the rotating shaft 32 (specifically, on the rotational axis O). In the following description, the direction in which the rotating shaft 32 extends is referred to as the axial direction, the direction radiating from the center of the rotating shaft 32 is referred to as the radial direction, and the direction circumferentially extending around the rotating shaft 32 is referred to as the circumferential direction.

[0021] 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 that protrude radially inward from the back yoke 51a. A plurality of slots 54 are formed between adjacent teeth 51b, arranged in the circumferential direction. The stator windings 52 are formed by housing the phase windings of each phase in a predetermined order in each slot 54. For example, a segment coil structure using a plurality of conductor segments may be adopted in the stator 50. However, the structure of the stator windings 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 pole portions 62 that protrude radially outward from the rotor core 61. In this embodiment, eight main pole portions 62 are provided at equal intervals in the circumferential direction. The main pole portions 62 extend in the axial direction.

[0023] The field winding 70 comprises a first winding section 71a and a second winding section 71b. In each main pole section 62, the first winding section 71a is wound radially outward, and the second winding section 71b is wound radially inward from the first winding section 71a. In each main pole section 62, the winding directions of the first winding section 71a and the second winding section 71b are the same. Furthermore, for two circumferentially adjacent main pole sections 62, the winding directions of the winding sections 71a and 71b wound on one are opposite to those of the winding sections 71a and 71b wound on the other. As a result, the magnetization directions of circumferentially adjacent main pole sections 62 are opposite to each other.

[0024] Figure 4 shows the electrical circuit on the rotor 60 side, which has windings 71a and 71b wound around a common main pole 62. The rotor 60 is provided with a diode 80 as a rectifier 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. Specifically, the first end of the first winding 71a is connected to the cathode of the diode 80, and the first end of the second winding 71b is connected to the second end of the first winding 71a. The anode of the diode 80 is connected to the second end of the second winding 71b. The capacitor 81 is electrically connected in parallel to the second winding 71b. In Figure 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 consisting of a first winding section 71a, a capacitor 81, and a diode 80 is configured, and a parallel resonant circuit consisting of a second winding section 71b and a capacitor 81 is configured. In Figure 4, f1 indicates the first resonant frequency, which is the resonant frequency of the series resonant circuit, and f2 indicates the second resonant frequency, which is the resonant frequency of the parallel resonant circuit.

[0026] Alternatively, the anode of diode 80 may be connected to the first end of the first winding portion 71a, and the cathode of diode 80 may be connected to the second end of the second winding portion 71b.

[0027] Returning to the explanation of Figure 2, the control device 30 is an electronic control unit (ECC) mainly composed of a microcontroller 31. The microcontroller 31 is equipped with a CPU (Central Processing Unit). The control device 30 generates drive signals to turn on and off each switch Sup to SWn that make up the inverter 20. More specifically, the control device 30 generates drive signals to turn on and off each arm switch Sup to SWn in order to convert the DC power output from the DC power supply 10 into AC power and supply it to the U, V, and W phase windings 52U, 52V, and 52W, and supplies the generated drive signals to the gates of each arm switch Sup to SWn.

[0028] The control device 30 switches switches Sup~SWn on and off to allow a combined current of the fundamental wave current and harmonic current to flow through each phase winding 52U, 52V, and 52W. The fundamental wave current is the current that primarily generates torque in the rotating electric machine 40. The harmonic current is the current that primarily excites the field winding 70 and induces a field current in the field winding 70. Due to the switching control of the inverter 20, a combined current consisting of the fundamental wave current and harmonic current superimposed flows through each phase winding 52U, 52V, and 52W. The phase currents flowing through each phase winding 52U, 52V, and 52W are shifted by 120° in electrical angle.

[0029] Next, the retaining member 90 attached to the rotor 60 will be described using Figures 3, 5, and 6. The retaining member 90 is a member that restricts the radial movement of the field winding 70 even when centrifugal force acts on the field winding 70 as the rotor 60 rotates. The retaining member 90 is made of a non-magnetic metallic material, such as aluminum or austenitic stainless steel (e.g., SUS). It is made of a non-magnetic material so as not to affect the magnetic circuit including the rotor 60 and stator 50.

[0030] The retaining member 90 comprises 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 span between circumferentially adjacent main pole portions 62. The outer plate portion 100 is shaped like a circular arc extending circumferentially with a convexity radially outward, and is also plate-shaped extending axially. The first winding portion 71a is covered by the outer plate portion 100.

[0031] The inner plate portion 110 is positioned radially between the first winding portion 71a and the second winding portion 71b, and is provided so as to span between the circumferentially adjacent main pole portions 62. The inner plate portion 110 is shaped like a circular arc extending circumferentially with a convexity radially outward, and is also plate-shaped extending axially. The second winding portion 71b is covered by the inner plate portion 110. The circumferential length dimension of the inner plate portion 110 is smaller than the circumferential length dimension of the outer plate portion 100.

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

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

[0034] First recesses 63 are formed at both circumferential ends of the tip of the main pole portion 62, which are recessed in the circumferential direction and extend in the axial direction. Second recesses 64 are formed at both circumferential ends of the axial middle portion of the main pole portion 62, which are recessed in the circumferential direction and extend in the axial direction. The second recesses 64 are formed in the portion of the main pole portion 62 between the first winding portion 71a and the second winding portion 71b in the axial direction.

[0035] By moving the retaining member 90 axially relative to the rotor 60, 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. As a result, the retaining member 90 is fixed to the main pole portion 62.

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

[0037] In other words, magnetic flux is generated when current is supplied to the stator winding 52. A portion of the generated magnetic flux becomes leakage flux and links with the retaining member 90. As a result, eddy current loss occurs in the retaining member 90. A retaining member 90 having a laminated structure of plate-shaped members 91 can increase the electrical resistance between layers, thereby reducing the eddy current loss generated in the retaining member 90.

[0038] Furthermore, the holding member 90 is constructed by integrating each plate-shaped member 91 by welding or crimping at least one of the inner plate portion 110 and the connecting portion 120 of each plate-shaped member 91 that constitute the holding member 90. Of the plate-shaped members 91 that constitute the holding member 90, the outer plate portion 100 does not have welding or crimping fixing points. This makes it possible to enhance the effect of reducing eddy current loss.

[0039] Figure 8 shows the calculated results of eddy current losses occurring in the outer plate portion 100 and the inner plate portion 110. As shown in Figure 8, the eddy current losses in the outer plate portion 100, which is relatively close to the stator winding 52, are significantly larger than the eddy current losses in the inner plate portion 110, which is relatively farther 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 the plate-shaped members 91 may peel off, causing at least a portion of the welded or crimped fixing points of each plate-shaped member 91 to become electrically connected. In this case, the effect of reducing eddy current loss decreases. Therefore, the effect of reducing eddy current loss is enhanced by making the inner plate portion 110 and the connecting portion 120, which have relatively small eddy current loss, the welded or crimped fixing points.

[0041] Figure 7 shows an example in which multiple locations on the inner plate portion 110 of each plate-shaped member 91 are welded and fixed. The welded portion 130 extends from one end to the other in the axial direction of the outer plate portion 100. In the example shown in Figure 7, the welded portion 130 is located near the connection point with the connecting portion 120, the radially outer portion of both ends in the circumferential direction, and the radially inner portion of the inner plate portion 110.

[0042] Furthermore, of each plate-shaped member 91, only the inner plate portion 110 and the connecting portion 120 may be welded or riveted, or only the connecting portion 120 may be welded or riveted. In addition, when using riveting, the plate-shaped members 91 can be integrated by compressing the riveted portion of each plate-shaped member 91 from the stacking direction and causing plastic deformation.

[0043] In this embodiment, in order to supply field current to the field winding 70 without using brushes, a harmonic current is superimposed on the current flowing through the stator winding 52. In this case, as the stator winding 52 is energized, harmonic flux is further generated, and a portion of the generated harmonic flux becomes leakage flux and links with the retaining member 90. For this reason, in a configuration in which a harmonic current is superimposed on the current flowing through the stator winding 52, the eddy current loss of the retaining member 90 tends to increase. In such a configuration, there is a great advantage to using a retaining member 90 having a laminated structure.

[0044] <Modified form of the first embodiment> • Of the plate-shaped members 91 that constitute the holding member 90, the outer plate portion 100 may be welded or riveted to fix each plate-shaped member 91, thereby integrating them into one unit. Even in this case, the effect of reducing eddy current loss can be obtained.

[0045] Each plate-shaped member 91 may be fixed with adhesive rather than by welding or riveting.

[0046] <Second Embodiment> The second embodiment will now be described, focusing on the differences from the first embodiment, with reference to the drawings. In this embodiment, as shown in Figure 9, each main pole portion 62 is provided with a flange portion 65 extending on both sides in the circumferential direction at its tip. The radially inner portion of the circumferential tip of the flange portion 65 is a recessed portion 66 that is recessed in the circumferential direction.

[0047] The retaining member 90 is positioned such that the first protrusion 101 of the outer plate portion 100 contacts the recess 66 of the flange portion 65 by moving the retaining member 90 relative to the rotor 60 in the axial direction. As a result, the circumferential tip of the flange portion 65 and the first protrusion 101 of the outer plate portion 100 overlap in the radial direction. Consequently, when centrifugal force generated by the rotation of the rotor 60 acts on the retaining member 90, both circumferential ends of the outer plate portion 100 can be supported by the circumferential tip of the flange portion 65.

[0048] Furthermore, a 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 the circumferentially adjacent main pole portion 62 and outer plate portion 100.

[0049] <Modified form of the second embodiment> The flange portion 65 does not necessarily have to have a recess 66 on the radially outer portion of its circumferential tip. In this case, the first protrusions 101 do not necessarily have to be provided on both circumferential ends of the outer plate portion 100.

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

[0051] Furthermore, the tip of the enlarged diameter portion 170a is provided with a flange portion 165 and a recess portion 166, similar to the second embodiment.

[0052] The boundary between the enlarged diameter portion 170a and the reduced diameter portion 170b is a stepped portion 167. In this embodiment, as shown in Figure 11, the holding member 90 does not have a second protrusion 111 on the inner plate portion 110. Both circumferential ends of the inner plate portion 110 are in contact with 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 segmented core that can be attached to and detached from the rotor core 61. A projection 168 is provided at the base end of the reduced-diameter portion 170b that constitutes the main pole portion 162, projecting radially. The projection 168 has a wedge shape, with its circumferential dimension increasing towards the radially inward side. Grooves 61a are formed at predetermined intervals in the circumferential direction on the radially outer portion of the rotor core 61. The grooves 61a open radially outward, and the circumferential groove width increases towards the radially inward side. The projections 168 are fitted into the grooves 61a.

[0054] By moving the main pole portion 162, around which the first winding portion 71a and the second winding portion 71b are wound, relative to the rotor core 61 in the axial direction, the protruding portion 168 of the main pole portion 162 is fitted into the groove portion 61a of the rotor core 61. This fixes the main pole portion 162 to the rotor core 61. Subsequently, by moving the retaining member 90 relative to the rotor 60 in the axial direction, the retaining member 90 is fixed to the main pole portion 162.

[0055] <Fourth Embodiment> The fourth embodiment will now be described, focusing on the differences from the second embodiment, with reference to the drawings. In this embodiment, a skew structure is adopted for the rotor 60 as shown in Figures 12 to 14 in order to reduce the torque ripple of the rotating electric machine 40. Figure 14 is a plan view of the tip of the main pole section unfolded in the circumferential direction. Figure 12 is a cross-sectional view of the rotor 60 corresponding to the line 12-12 in Figure 14, and Figure 13 is a cross-sectional view of the rotor 60 corresponding to the line 13-13 in Figure 13.

[0056] Of the main pole portions extending in the axial direction, the portion on one side from the axial center is the first main pole portion 262A shown in Figure 12, and the portion on the other side is the second main pole portion 262B shown in Figure 13. The dashed line in Figure 14 represents a virtual plane extending radially through the rotation center O of the rotation axis 32 (see Figure 3).

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

[0058] The radially inner portion of the circumferential tip of the first long-side flange portion 265A is a first long-side recess 267A that is recessed in the circumferential direction. The radially inner portion of the circumferential tip of the first short-side flange portion 266A is a first short-side recess 268A that is recessed in the circumferential direction. The first long-side protrusion 267A and the first short-side protrusion 268A are in contact with the first protrusion 101 of the outer plate portion 100, similar to the second embodiment.

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

[0060] The radially inner portion of the circumferential tip of the second short-side flange portion 265B is a circumferentially recessed second short-side recess 267B. The radially inner portion of the circumferential tip of the second long-side flange portion 266B is a circumferentially recessed second long-side recess 268B. 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, similar to the second embodiment. In this embodiment, the retaining member 90 fixed to the second main pole portion 262B and the retaining member 90 fixed to the first main pole portion 262A are separate members.

[0061] As shown in Figure 14, θnt is the amount of circumferential displacement 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. The amount of circumferential displacement 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, if the 1-slot pitch of the stator 50 is β (see Figure 3), then "1 / 3 × β < θnt < 2 / 3 × β" is set. This reduces torque ripple. In particular, in this embodiment, "θnt = β / 2" is set. This enhances the torque ripple reduction effect.

[0062] In this embodiment, the axial length La of the first main electrode portion 262A is equal to the axial length La of the second main electrode portion 262B. This further enhances the torque ripple reduction effect.

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

[0064] <Fifth Embodiment> The fifth embodiment will now be described, focusing on the differences from the first embodiment, with reference to the drawings. In this embodiment, as shown in Figure 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 the radial and circumferential directions. If the one-slot pitch of the stator 50 is β (see Figure 3) and the width of the notch 300 in the circumferential direction is θnt, then "1 / 3 × β < θnt < 2 / 3 × β" is set, and specifically "θnt = β / 2". This reduces the torque ripple of the rotating electric machine 40.

[0065] Here, if a notch 300 is provided at the tip of the main pole portion 62, the support portion at the circumferential end of the outer plate portion 100 will be lost. Therefore, in this embodiment, as shown in Figures 16 to 18, a non-magnetic member 400 (corresponding to the "non-magnetic portion") made of a non-magnetic synthetic resin is provided in the missing portion of the tip of the main pole portion 62 due to the notch 300. The non-magnetic member 400 extends in the axial direction. The circumferential width of the non-magnetic member 400 is the same as the circumferential width of the notch 300, θnt. By making the non-magnetic member 400 that fills the missing portion out 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 that is 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 portion 62 will be explained using Figures 17 and 18.

[0068] The non-magnetic member 400 is provided with axially extending protrusions 402 at both axial ends. The tip of the main pole portion 62 is provided with circumferentially recessed grooves 301 at both axial ends. By moving the non-magnetic member 400 relative to the main pole portion 62 in the circumferential direction, the protrusions 402 of the non-magnetic member 400 are fitted into the grooves 301 of the main pole portion 62. This fixes the non-magnetic member 400 to the main pole portion 62.

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

[0070] <Modified form 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 Figure 19, notches may be formed at both circumferential ends of the tip of each main pole portion 62. Figure 19 is a plan view of the tip of the main pole portion 62 unfolded in the circumferential direction.

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

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

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

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

[0076] <Sixth Embodiment> The sixth embodiment will now be described, focusing on the differences from the fifth embodiment, with reference to the drawings. In this embodiment, as shown in Figure 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 having electrical insulating properties, such as synthetic resin. The first insulating member 600 has a wedge shape and functions as a wedge between the first winding portion 71a and the connecting portion 120. The second insulating member 601 has a wedge shape 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 embodiment described above, the field winding 70 can be firmly fixed, and the resistance of the rotating electric machine 40 to centrifugal force and vibration can be increased.

[0078] <Other Embodiments> Furthermore, each of the above embodiments may be implemented with the following modifications.

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

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

[0081] The retaining member 90 does not necessarily have to have a connecting portion 120. In other words, in this case, the retaining member 90 may consist of 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 retaining member 90 does not necessarily have to have a connecting portion 120 and an inner plate portion 110. In other words, in this case, the retaining member 90 may consist of the outer plate member described above.

[0082] The rotating electric machine is not limited to an inner rotor type; it may also be an outer rotor type. In this case, the main pole portion protrudes radially inward from the rotor core. Even in an outer rotor type rotating electric machine, a retaining member can be provided to cover the field winding from the radially inward side in order to prevent the field winding from being exposed between adjacent main pole portions in the circumferential direction.

[0083] The rotating electric machine is not limited to a star-connected rotating electric machine; a delta-connected rotating electric machine may also be used.

[0084] The stator core may be one without teeth.

[0085] The configuration for supplying field current to the field winding is not limited to the circuit shown in Figure 4. For example, a configuration comprising a brush electrically connected to the field winding and a power supply electrically connected to the brush may also be used. In this case, it is not necessary to apply a harmonic voltage to induce field current to the stator winding.

[0086] The rotating electric machine is not limited to those used as vehicle-mounted main engines; for example, it may also be a rotating electric machine used as an ISG (Integrated Starter Generator), which is both an electric motor and a generator.

[0087] The mobile body on which the control system is installed is not limited to a vehicle; for example, it may be an aircraft or a ship. Furthermore, the control system is not limited to a system installed on a mobile body; it may be a stationary system. [Explanation of Symbols]

[0088] 40...Rotating electric machine, 50...Stator, 52...Stator winding, 60...Rotor, 70...Field winding, 90...Retaining 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 magnetic pole arranged in the circumferential direction and projecting radially from the rotor core toward the stator side, The field winding (70) wound around each of the aforementioned main poles, A retaining member (90) is provided between adjacent main pole portions in the circumferential direction and attached to the rotor, covering the field winding from the stator side, Equipped with, The field winding has a first winding section (71a) and a second winding section (71b) that are electrically connected in series. The first winding section is positioned radially closer to the stator than the second winding section. The holding member is constructed by stacking plate-shaped members (91) made of metal material in the axial direction. The aforementioned retaining member is A first plate portion (100) is provided on the stator side relative to the first winding portion in the radial direction, and covers the first winding portion from the stator side, A second plate portion (110) is provided radially between the first winding portion and the second winding portion, and covers the second winding portion from the stator side, A connecting portion (120) is provided between adjacent first winding portions in the circumferential direction and extends radially to connect the first plate portion and the second plate portion, It has, A rotating electric machine in which, of the plate-shaped members constituting the holding member, at least one of the second plate portion and the connecting portion is welded or riveted to fix the plate-shaped members together.

2. 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 magnetic pole arranged in the circumferential direction and projecting radially from the rotor core toward the stator side, The field winding (70) wound around each of the aforementioned main poles, A retaining member (90) is provided between adjacent main pole portions in the circumferential direction and attached to the rotor, covering the field winding from the stator side, Equipped with, The field winding has a first winding section (71a) and a second winding section (71b) that are electrically connected in series. The first winding section is positioned radially closer to the stator than the second winding section. The holding member is constructed by stacking plate-shaped members (91) made of metal material in the axial direction. The aforementioned retaining member is A first plate portion (100) is provided on the stator side relative to the first winding portion in the radial direction, and covers the first winding portion from the stator side, A second plate portion (110) is provided radially between the first winding portion and the second winding portion, and covers the second winding portion from the stator side, A connecting portion (120) is provided between adjacent first winding portions in the circumferential direction and extends radially to connect the first plate portion and the second plate portion, It has, Of the plate-shaped members constituting the holding member, at least one of the portion of the second plate and the portion of the connecting part is welded or riveted to fix the plate-shaped members together. The stator is, Back yoke (51a) and Multiple teeth (51b) are provided in a circumferential direction and protrude radially from the back yoke toward the rotor, It has, At least one of the circumferential ends of the tip portion of the main pole portion (62) has axially extending notches (300, 310A, 310B) formed therein. If the slot pitch of the stator is β and the width of the notch in the circumferential direction is θnt, then "1 / 3 × β < θnt < 2 / 3 × β" is given. In the main electrode portion, the portion missing due to the notch is provided with a non-magnetic portion (400, 500) made of a non-magnetic material. A rotating electric machine, wherein the circumferential end of the tip of the main pole and the non-magnetic portion are provided with recesses (401, 501) that are recessed in the circumferential direction, into which the circumferential end of the first plate portion is fitted.

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

4. 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 magnetic pole arranged in the circumferential direction and projecting radially from the rotor core toward the stator side, The field winding (70) wound around each of the aforementioned main poles, A retaining member (90) is provided between adjacent main pole portions in the circumferential direction and attached to the rotor, covering the field winding from the stator side, Equipped with, The field winding has a first winding section (71a) and a second winding section (71b) that are electrically connected in series. The first winding section is positioned radially closer to the stator than the second winding section. The holding member is constructed by stacking plate-shaped members (91) made of metal material in the axial direction. The aforementioned retaining member is A first plate portion (100) is provided on the stator side relative to the first winding portion in the radial direction, and covers the first winding portion from the stator side, A second plate portion (110) is provided radially between the first winding portion and the second winding portion, and covers the second winding portion from the stator side, A connecting portion (120) is provided between adjacent first winding portions in the circumferential direction and extends radially to connect the first plate portion and the second plate portion, It has, Of the plate-shaped members constituting the holding member, at least one of the portion of the second plate and the portion of the connecting part is welded or riveted to fix the plate-shaped members together. The main electrode portion has a first main electrode portion (262A) and a second main electrode portion (262B), The tip of the first main pole is provided with a first long flange (265A) extending in the first direction in the circumferential direction, and a first short flange (266A) extending in the second direction opposite to the first direction in the circumferential direction. The circumferential length dimension of the first long side flange is greater than the circumferential length dimension of the first short side flange. The tip of the second main pole is provided with a second short flange (265B) extending in the first direction in the circumferential direction, and a second long flange (266B) extending in the second direction in the circumferential direction. The circumferential length dimension of the second short flange is shorter than the circumferential length dimension of the second long flange. A rotating electric machine in which, when the circumferential displacement between the circumferential tip of the first long flange and the circumferential tip of the second short flange is θnt, and the circumferential displacement between the circumferential tip of the first short flange and the circumferential tip of the second long flange is θnt, and the one-slot pitch of the stator is β, the relationship "1 / 3 × β < θnt < 2 / 3 × β" holds.

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

6. 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 magnetic pole arranged in the circumferential direction and projecting radially from the rotor core toward the stator side, The field winding (70) wound around each of the aforementioned main poles, A retaining member (90) is provided between adjacent main pole portions in the circumferential direction and attached to the rotor, covering the field winding from the stator side, Equipped with, The field winding has a first winding section (71a) and a second winding section (71b) that are electrically connected in series. The first winding section is positioned radially closer to the stator than the second winding section. The holding member is constructed by stacking plate-shaped members (91) made of metal material in the axial direction. The aforementioned retaining member is A first plate portion (100) is provided on the stator side relative to the first winding portion in the radial direction, and covers the first winding portion from the stator side, A second plate portion (110) is provided radially between the first winding portion and the second winding portion, and covers the second winding portion from the stator side, A connecting portion (120) is provided between adjacent first winding portions in the circumferential direction and extends radially to connect the first plate portion and the second plate portion, It has, Of the plate-shaped members constituting the holding member, at least one of the portion of the second plate and the portion of the connecting part is welded or riveted to fix the plate-shaped members together. Of the main pole portion (162), the circumferential length dimension of the reduced diameter portion (170b), which is the portion on the rotor core side in the radial direction, is smaller than the circumferential length dimension of the enlarged diameter portion (170a), which is the portion on the stator side in the radial direction. A rotating electric machine in which both circumferential ends of the second plate portion are supported by the stepped portion (167) between the enlarged diameter portion and the reduced diameter portion.

7. The rotor is A diode (80) electrically connected in parallel to the series connection of the first winding section and the second winding section, A capacitor (81) electrically connected in parallel to either the first winding section or the second winding section, It has, The rotating electric machine according to any one of claims 1 to 6, wherein a harmonic current for inducing a field current in the field winding is configured to flow through the stator winding.

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