Coil field magnet type rotary electric machine

Abstract

To properly dispose a stator and a rotor opposite to each other in a radial direction.SOLUTION: A rotary electric machine includes a stator 50 having a stator winding 52, and a rotor 60 having a field magnetic winding 70, and the rotor 60 is oppositely disposed radially inside the stator 50. In the stator winding 52, a radial inside diameter of a second stator coil end SE2 is smaller than a radial inside diameter of a first stator coil end SE1. In the field magnetic winding 70, a radial outer diameter of a second rotor coil end RE2 is smaller than a radial outer diameter of a first rotor coil end RE1. The stator winding 52 and the field magnetic winding 70 are disposed such that the first stator coil end SE1 and the first rotor coil end RE1 are radially aligned, and the second stator coil end SE2 and the second rotor coil end RE2 are radially aligned.SELECTED DRAWING: Figure 14

Description

[Technical Field]

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

[0002] A wound-field rotating electric machine has a stator with a stator winding and a rotor with a field winding. The rotor has a rotor core with multiple main poles (magnetic salient poles), and the field winding is wound around the main poles (see, for example, Patent Document 1). In an inner-rotor rotating electric machine, the rotor is disposed radially inside the stator, facing it. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-9553 Summary of the Invention [Problem to be solved by the invention]

[0004] In a wound-field rotating electric machine, the coil ends of the stator winding and the coil ends of the field winding are arranged in radially aligned positions, which raises concerns that the coil ends of the stator winding and the field winding may interfere with each other.

[0005] Specifically, the stator winding is wound, for example, by distributed winding at a predetermined slot pitch in the circumferential direction. Furthermore, on the coil side of the stator winding (the portion of the stator slot where the conductors are housed), the conductors are arranged in multiple layers in the radial direction, while at the coil ends, the conductors are arranged more radially apart than on the coil side to prevent interference between the conductors. In this case, the coil ends of the stator winding are shifted radially inward relative to the coil sides, raising concerns about interference with the coil ends of the field winding. The coil end portions are relatively prone to deformation, and technological improvements are desirable.

[0006] The present disclosure has been made in consideration of the above circumstances, and aims to provide a wound-field rotating electric machine in which the stator and rotor can be disposed radially opposite each other in an appropriate state. [Means for solving the problem]

[0007] The present disclosure provides: a stator having stator windings; a rotor having a rotor core including a plurality of main pole portions provided for magnetic poles aligned in the circumferential direction, and a field winding wound around each of the main pole portions; a rotor disposed radially inside the stator to face the rotor, the stator winding has a first stator coil end at one axial end and a second stator coil end at the other axial end, and the inner diameter dimension of the radially inner side of the second stator coil end is smaller than the inner diameter dimension of the radially inner side of the first stator coil end, the field winding includes a plurality of pole coils provided for each magnetic pole, and has a first rotor coil end on one axial end side and a second rotor coil end on the other axial end side, the outer diameter dimension of the second rotor coil end on the radial outside being smaller than the outer diameter dimension of the first rotor coil end on the radial outside, The stator winding and the field winding are respectively arranged so that the first stator coil end and the first rotor coil end are aligned radially, and the second stator coil end and the second rotor coil end are aligned radially.

[0008] In an inner rotor type rotating electric machine, reducing the outer diameter of the stator winding coil ends is effective for reducing the size of the stator, and it is preferable to configure at least one stator coil end to be offset radially inward. However, considering that the rotor is assembled to the radial inside of the stator, it is undesirable for the inner diameter of the coil end on one axial side of the stator winding to be excessively small. In this regard, by making the inner diameters of the stator coil ends on both axial sides of the stator winding different, it is possible to achieve a compact stator while improving the ease of assembly of the stator and rotor.

[0009] On the other hand, for the rotor field winding, it is desirable to wind the conductor wire multiple times in both the radial and circumferential directions around the main pole to increase the number of turns of the pole coil of each magnetic pole. Furthermore, by reducing the outer diameter of one of the rotor coil ends on both axial sides of the field winding, a suitable configuration can be realized on the rotor side that takes into account ease of assembly to the stator. In this case, by arranging the stator winding and field winding so that the first stator coil end with a relatively large inner diameter and the first rotor coil end with a relatively large outer diameter are aligned radially, and the second stator coil end with a relatively small inner diameter and the second rotor coil end with a relatively small outer diameter are aligned radially, the stator and rotor can be easily assembled. As a result, the stator and rotor can be positioned radially opposite each other in an appropriate manner. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is an overall configuration diagram of a control system for a rotating electrical machine. [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] FIG. 2 is a perspective view showing the overall configuration of the rotor. [Figure 6]FIG. 4 is a perspective view showing a rotor with an outer circumferential covering portion and a coil end cover removed. [Figure 7] FIG. [Figure 8] FIG. [Figure 9] FIG. 3 is an exploded perspective view of a winding unit in the rotor main portion. [Figure 10] FIG. 3 is a cross-sectional view showing a cross-sectional structure of a part of a rotor main portion. [Figure 11] FIG. [Figure 12] FIG. [Figure 13] FIG. 4 is a perspective view showing a state in which the rotor is assembled to the stator. [Figure 14] FIG. 4 is a vertical cross-sectional view showing a state in which the rotor is assembled to the stator. [Figure 15] FIG. 2 is a cross-sectional view showing the configuration of a vertical cross section of a stator. [Figure 16] FIG. 2 is a cross-sectional view showing the configuration of a longitudinal section of a rotor. [Figure 17] FIG. [Figure 18] FIG. 3 is a diagram showing the winding structure of a winding unit. [Figure 19] FIG. 4 is an enlarged longitudinal cross-sectional view showing a portion where a second stator coil end and a second rotor coil end are arranged side by side. DETAILED DESCRIPTION OF THE INVENTION

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A wound-field rotating electric machine according to an embodiment of the present disclosure is used as a power source for driving electric vehicles such as electric vehicles and hybrid vehicles.

[0012] First, a control system including a rotating electric machine will be described with reference to Fig. 1. The control system includes a DC power supply 10, an inverter 20, a control device 30, and a rotating electric machine 40. The rotating electric machine 40 is a self-excited wound field type synchronous machine. For example, the rotating electric machine 40, the inverter 20, and the control device 30 may be configured as an electromechanical integrated drive device, or the rotating electric machine 40, the inverter 20, and the control device 30 may each be configured with its own 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 preferably made of a conductor material such as aluminum wire, which has a low specific gravity and is easily formed. The conductor material of the field winding 70 is not limited to aluminum wire, and may be, for example, copper wire or CNT (carbon nanotube). A rotating shaft 32 is assembled in the center hole of the rotor core 61. The rotating shaft 32 is rotatably supported in the housing 41 by bearings 42 and 43.

[0016] As shown in FIG. 2, the inverter 20 includes a series connection of upper-arm switches SUp, SVp, and SWp for U, V, and W phases and lower-arm switches SUn, SVn, and SWn for U, V, and W phases. First ends of U, V, and W-phase windings 52U, 52V, and 52W are connected to the connection points between the upper-arm switches SUp, SVp, and SWp and the lower-arm switches SUn, SVn, and SWn for each phase. Second ends of the U, V, and W-phase windings 52U, 52V, and 52W are connected at the neutral point. That is, in this embodiment, the stator winding 52 is star-connected. However, the stator winding 52 may also be delta-connected. In this embodiment, each of the switches SUp to SWn is, for example, an IGBT. A freewheel diode is connected in antiparallel to each of the switches SUp to SWn.

[0017] The collectors of the upper arm switches SUp, SVp, SWp of each phase are connected to the positive terminal of a DC power supply 10. The emitters of the lower arm switches SUn, SVn, SWn of each phase are connected to the negative terminal of the DC power supply 10. A smoothing capacitor 11 is connected in parallel to the DC power supply 10.

[0018] Next, the stator 50 and the rotor 60 will be described with reference to FIG.

[0019] The stator 50 and the rotor 60 are both arranged coaxially 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.

[0020] The stator core 51 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 a predetermined order in each of these slots 54. For example, the stator 50 may employ a segment coil structure using multiple conductor segments. However, the structure of the stator winding 52 is arbitrary.

[0021] The rotor core 61 is made of a soft magnetic material, for example, laminated steel plates. The rotor core 61 has a cylindrical portion 61a and a plurality of main pole portions 62 extending radially outward from the cylindrical portion 61a. A field winding 70 is wound around the main pole portions 62 by concentrated winding. In this embodiment, eight main pole portions 62 are provided at equal intervals in the circumferential direction.

[0022] The field winding 70 includes a first winding portion 71 and a second winding portion 72. The first winding portion 71 is wound radially outward around each main pole portion 62, and the second winding portion 72 is wound radially inward relative to the first winding portion 71. In each main pole portion 62, the winding directions of the conductor wire in the first winding portion 71 and the second winding portion 72 are the same. Furthermore, among circumferentially adjacent main pole portions 62, the winding direction of each winding portion 71, 72 wound around one is opposite to the winding direction of each winding portion 71, 72 wound around the other. Therefore, the magnetization directions of circumferentially adjacent main pole portions 62 are opposite to each other. In the rotor 60, each main pole portion 62 in the rotor core 61 and the field winding 70 wound around each main pole portion 62 form a plurality of magnetic poles (field poles) arranged in the circumferential direction.

[0023] 4 is a diagram showing an electric circuit including the first and second winding portions 71 and 72 in the rotor 60. The first winding portion 71 and the second winding portion 72 are connected in series by connecting the second end 71b of the first winding portion 71 to the first end 72a of the second winding portion 72. A diode 91 and a capacitor 92 are connected to the second end 71b of the first winding portion 71 in parallel with the second winding portion 72. A diode 93 and a capacitor 94 are connected in series to the series connection of the first winding portion 71 and the second winding portion 72. The capacitors 92 and 94 are, for example, ceramic capacitors or film capacitors.

[0024] The cathode of the diode 91 is connected to the first end 72a of the second winding portion 72, and the anode is connected to the second end 72b of the second winding portion 72. As a result, in a closed circuit including the second winding portion 72 and the diode 91, current flows in one direction, from the anode side to the cathode side of the diode 91. Furthermore, the cathode of the diode 93 is connected to the first end 71a of the first winding portion 71, and the anode is connected to the second end 72b of the second winding portion 72. As a result, the field current flowing through each of the winding portions 71, 72 is rectified. In this embodiment, the number of windings of the second winding portion 72 is greater than the number of windings of the first winding portion 71.

[0025] Returning to the description of FIG. 2 , the control device 30 is an electronic control unit (EC) primarily composed of a microcomputer 31. The microcomputer 31 includes a central processing unit (CPU). The functions provided by the microcomputer 31 can be provided by software stored in a physical memory device and a computer executing the software, software alone, hardware alone, or a combination thereof. For example, if the microcomputer 31 is provided by hardware electronic circuits, the functions can be provided by digital circuits including multiple logic circuits or analog circuits. For example, the microcomputer 31 executes programs stored in a non-transitory tangible storage medium (NSS) that serves as its own storage unit. The programs include programs for controlling the rotating electric machine 40. A method corresponding to the programs is performed by executing a set of instructions that constitute the programs. The storage unit is, for example, a non-volatile memory. The programs stored in the storage unit can be updated via a communication network such as the Internet, for example, via OTA (Over The Air) or other means.

[0026] Control device 30 generates drive signals that turn on and off each of switches SUp to SWn that constitute inverter 20. Specifically, control device 30 generates drive signals that turn on and off each of switches SUp to SWn and outputs the generated drive signals to the gates of each of switches SUp to SWn in order to convert DC power output from DC power supply 10 into AC power and supply it to U-, V-, and W-phase windings 52U, 52V, and 52W. As a result, in each phase, the upper arm switches and the lower arm switches are alternately turned on with dead times therebetween.

[0027] Control device 30 turns on and off each of switches SUp to SWn so as to pass a composite current of a fundamental current and a high-frequency current (specifically, a high-frequency excitation current) having a frequency higher than that of the fundamental current through each of phase windings 52U, 52V, 52W. The fundamental current is a current that mainly serves to generate torque in rotating electric machine 40. The high-frequency current is a current that mainly serves to excite first and second winding portions 71 and 72 that constitute field winding 70, thereby inducing a field current in field winding 70. The phase currents flowing through phase windings 52U, 52V, 52W are shifted by 120 electrical degrees.

[0028] The high-frequency current flowing through the stator winding 52 may be a harmonic current whose fluctuating frequency is N times (N is an integer greater than or equal to 2) the frequency of the fundamental current, or may be a current whose fluctuating frequency is different from N times the frequency of the fundamental current.

[0029] When a high-frequency current flows through the stator winding 52, a voltage is induced in the first and second winding portions 71 and 72, causing a field current to flow. The induced voltages in the first and second winding portions 71 and 72 are, for example, in phase. The currents IL1 and IL2 flowing through the first and second winding portions 71 and 72 contain frequency components of the high-frequency current.

[0030] 4, when the first and second winding portions 71, 72 are excited by energizing the stator winding 52, a current flows from the first winding portion 71 to the second winding portion 72. Furthermore, when the voltage across the second winding portion 72 exceeds the forward voltage of the diode 91, a current IL2, which is greater than the current IL1 flowing through the first winding portion 71, flows through the closed circuit including the second winding portion 72 and the diode 91. The flow of current through the closed circuit including the second winding portion 72 and the diode 91 increases the DC component of the field current. This increases the DC component of the magnetic flux of the rotor 60, thereby increasing the torque of the rotating electric machine 40.

[0031] Next, the configuration of the rotor 60 will be described in more detail. Fig. 5 is a perspective view showing the overall configuration of the rotor 60, and Fig. 6 is a perspective view showing the rotor 60 with the outer covering portion 102 that covers the rotor main portion 101 and the coil end covers 103, 104 removed. Fig. 7 is an exploded perspective view of the rotor 60, and Fig. 8 is a vertical cross-sectional view of the rotor 60.

[0032] The rotor 60 is broadly divided into a rotor main section 101, a cylindrical outer covering section 102 provided to surround the outer periphery of the rotor main section 101, coil end covers 103 and 104 attached to one and the other axial ends of the rotor main section 101, and a busbar module 105 and a circuit module 106 provided at one of both axial ends of the rotor main section 101. The rotor main section 101 includes a rotor core 61 and a field winding 70, and the rotating shaft 32 is attached to the center hole of the rotor core 61. The field winding 70 is made up of a plurality of winding units 110 arranged in a circumferential direction. The coil end covers 103 and 104 are provided to cover the coil ends of the field winding 70 on both axial sides.

[0033] The busbar module 105 and the circuit module 106 are fixed to the rotating shaft 32 with the rotating shaft 32 inserted through each hollow portion, so that the busbar module 105 and the circuit module 106 are provided at positions axially facing the coil end portions of the field winding 70. The busbar module 105 has a plurality of bus bars for electrically connecting the winding units 110 for each magnetic pole.

[0034] The circuit module 106 has a component holder 107 that houses electrical components, and a heat sink 108 that is placed over the component holder 107. The component holder 107 and the heat sink 108 are integrated with their axial end faces joined together. The component holder 107 holds diodes 91 and 93 and capacitors 92 and 94 as electrical components.

[0035] Heat sink 108 is fixed to one of the axial ends of component holder 107, on the side opposite rotor core 61 (the right side in the figure). Heat sink 108 is made of, for example, aluminum. By fixing heat sink 108 to the axial end face of component holder 107, heat generated in diodes 91 and 93 and capacitors 92 and 94 when current is applied to component holder 107 is released via heat sink 108.

[0036] The outer covering portion 102 is formed by using a metal wire 131 and winding the wire 131 in multiple layers around the outer periphery of the plurality of winding units 110 assembled to the rotor core 61 .

[0037] Fig. 9 is an exploded perspective view of the winding unit 110 in the rotor main section 101, and Fig. 10 is a cross-sectional view showing the cross-sectional structure of a portion of the rotor main section 101. Note that Fig. 10 depicts the outer circumferential covering section 102 shown in Fig. 5 and other figures as a structure for holding the field winding 70 wound around the main pole section 62 of the rotor core 61.

[0038] The rotor main section 101 has a plurality of winding units 110, one for each magnetic pole of the rotor 60. Each winding unit 110 is formed in an annular shape with the axial direction as the longitudinal direction, and is assembled to the rotor core 61 with the main pole section 62 of the rotor core 61 inserted into its hollow section. In this embodiment, the winding units 110 form a "pole coil."

[0039] The winding unit 110 has a first coil module 111 that is on the radially outer side when attached to the main pole section 62, and a second coil module 112 that is on the radially inner side. The first coil module 111 is a coil module that corresponds to the first winding section 71, and the second coil module 112 is a coil module that corresponds to the second winding section 72.

[0040] The first coil module 111 has an annular coil body 121 formed by winding a conductor material made of a rectangular wire multiple times in the circumferential and radial directions, and a thin plate-like insulator 122 provided integrally with the coil body 121. The insulator 122 has a portion that extends in the circumferential direction and covers the outer peripheral portions on the radially outer and inner sides of the coil body 121, and a portion that extends in the radial direction and covers the hollow portion of the coil body 121. In other words, the outer peripheral portion on the radially outer side, the inner peripheral portion on the radially inner side, and the hollow portion of the coil body 121 are insulated and coated with the insulator 122.

[0041] The second coil module 112 has an annular coil body 123 formed by winding a conductor material made of a rectangular wire multiple times in the circumferential and radial directions, and a thin plate-like insulator 124 provided integrally with the coil body 123. The insulator 124 has a portion that extends circumferentially and covers the outer peripheral portions on the radially outer and inner sides of the coil body 123, and a portion that extends radially and covers the hollow portion of the coil body 123. In other words, the outer peripheral portion on the radially outer side, the inner peripheral portion on the radially inner side, and the hollow portion of the coil body 123 are insulated and coated with the insulator 124.

[0042] The coil body 121 of the first coil module 111 is, for example, an α-winding coil in which a conductive wire is wound in an α-winding manner. The coil body 123 of the second coil module 112 is a continuously wound coil in which a conductive wire is continuously wound in a predetermined circumferential direction. In the first coil module 111, two conductive wire ends 125 are drawn out in the axial direction, and in the second coil module 112, two conductive wire ends 126 are drawn out in the axial direction. In each of the winding units 110 arranged in the circumferential direction, the conductive wire ends 125, 126 are connected to each other, so that the multiple first coil modules 111 provided on each main pole part 62 are connected in series, and the multiple second coil modules 112 provided on each main pole part 62 are connected in series.

[0043] The conductor wire used for the coil bodies 121, 123 is, for example, a flat wire having a substantially rectangular cross section (specifically, a substantially rectangular shape). The flat wire is composed of a conductor portion made of aluminum or the like and an insulating layer covering the conductor portion. However, a round wire having a circular cross section can also be used as the conductor wire. Note that the coil structure of each coil module 111, 112 is optional; for example, the coil bodies 121, 123 can both be continuous wound coils.

[0044] As shown in Fig. 10, the first coil module 111 has two radially wound layers of conductive wire, while the second coil module 112 has twelve radially wound layers of conductive wire. The number of layers in each of the coil modules 111, 112 is arbitrary, but it is preferable that the number of layers in the second coil module 112 is greater than the number of layers in the first coil module 111. The coil modules 111, 112 have different numbers of circumferential windings (in other words, the number of rows of conductive wire in the circumferential direction), with the number of windings being greater on the radially outer side than on the radially inner side. This improves the space factor of the field winding 70.

[0045] Next, the outer peripheral covering portion 102 and coil end covers 103, 104 that are provided in the rotor 60 to surround the rotor core 61 and the field winding 70 will be described. The configurations of the coil end covers 103, 104 are shown in Fig. 5 and Fig. 11. Fig. 5 is a perspective view of the rotor 60, with the coil end cover 103 on the circuit module 106 side, of the coil end covers 103, 104 on both axial sides, facing forward, and Fig. 11 is a perspective view of the rotor 60, with the coil end cover 104 on the opposite side from the circuit module 106, of the coil end covers 103, 104 on both axial sides facing forward.

[0046] The rotor 60 is provided with coil end covers 103, 104 on both axial sides of an outer circumferential covering portion 102. The axial range in which the outer circumferential covering portion 102 is provided is a range that radially overlaps with the rotor core 61, and this range X is shown in Figure 8. In range X, the main pole portions 62 and winding units 110 are lined up in the circumferential direction, and the outer circumferential covering portion 102 is formed by spirally and multiple-wound wire 131 on the radial outside of each of the main pole portions 62 and winding units 110. Range X is a range that corresponds to the rotor coil side of the field winding 70, which is between the rotor coil ends on both axial sides.

[0047] The outer covering portion 102 may be configured as shown in FIG. 12 . FIG. 12 is a longitudinal cross-sectional view of the outer covering portion 102, with the left-right direction being the axial direction and the up-down direction being the radial direction. In FIG. 12 , the wire materials 131 are wound in multiple layers (four layers in the figure) in the radial direction while contacting each other in the axial direction. The wire materials 131 may be steel flat wires having a rectangular cross section. The wire materials 131 may also be magnetic materials, specifically, SUS430, SUS631, piano wire, or the like. By using flat wire as the wire materials 131, gaps between the wire materials 131 in the outer covering portion 102 are less likely to form. This prevents the wire materials 131 from collapsing or deforming in the outer covering portion 102. Furthermore, the space factor of the outer covering portion 102 is increased, thereby increasing the strength of the outer covering portion 102.

[0048] Furthermore, in the outer circumferential covering portion 102, the wire rods 131 are wound in a state where they are linearly aligned in both the axial and radial directions. In this case, since the wire rods 131 are wound in a state where they are aligned in the axial direction, the outer circumferential surface (the circumferential surface on the outer radial side) of the outer circumferential covering portion 102 becomes flat. Therefore, the mechanical space between the rotor 60 and the stator 50 (the gap between the outer circumferential surface of the outer circumferential covering portion 102 and the stator 50) can be made constant in the axial direction. Furthermore, since the wire rods 131 are wound in a state where they are aligned in the radial direction, the outer circumferential covering portion 102 is divided at predetermined intervals in the axial direction. Therefore, eddy currents are reduced in the outer circumferential covering portion 102.

[0049] The outer covering portion 102 and the coil end covers 103, 104 are provided radially outside the main pole portion 62 and the field winding 70, and are continuous in the axial direction with their axial end faces facing each other.

[0050] As shown in FIG. 5 , the coil end cover 103 has an end plate portion 141, which is a portion fixed to the rotating shaft 32, and an annular portion 142, which extends axially from the outer periphery of the end plate portion 141 and surrounds the coil ends (rotor coil ends) of the field winding 70 from the radially outer side. In the coil end cover 103, the end plate portion 141 is a portion that faces the rotor coil ends and the circuit module 106 in the axial direction, and the annular portion 142 is a portion that surrounds the rotor coil ends from the radially outer side. The end plate portion 141 is provided with a central hole provided in the radial center, with the rotating shaft 32 inserted through it. The annular portion 142 is assembled to the axial end of the winding unit 110 (more specifically, the axial end of the insulator 122 of the first coil module 111).

[0051] 11, the coil end cover 104 has an end plate portion 151, which is a portion fixed to the rotating shaft 32, and an annular portion 152, which extends axially from the outer periphery of the end plate portion 151 and surrounds the coil ends (rotor coil ends) of the field winding 70 from the radially outer side. In the coil end cover 104, the end plate portion 151 is a portion that faces the rotor coil ends in the axial direction, and the annular portion 152 is a portion that surrounds the rotor coil ends from the radially outer side. The end plate portion 151 is provided with a central hole provided in the radial center, through which the rotating shaft 32 is inserted. The annular portion 152 is assembled to the axial end of the winding unit 110 (more specifically, the axial end of the insulator 122 of the first coil module 111).

[0052] In the coil end cover 104, the outer peripheral side of the annular portion 152 forms an inclined surface that is inclined with respect to the axial direction and approaches the rotor axis on the side of the end plate portion 141, and the ends of the wire 131, which form the start and end of the winding of the outer peripheral covering portion 102, are pulled out in the axial direction along this inclined surface.

[0053] In the rotating electric machine 40, the coil ends of the stator winding 52 and the coil ends of the field winding 70 are arranged side by side in radially adjacent positions at both axial ends. In this case, there is a concern that the coil ends of the stator winding 52 may interfere with members on the rotor coil end side. In particular, if the coil ends on both axial ends of the stator winding 52 have different shapes, and if the coil ends on both axial ends of the field winding 70 have different shapes, there is a concern that the coil ends of the stator winding 52 may interfere with the rotor coil end side.

[0054] Fig. 13 is a perspective view showing the state in which the rotor 60 is assembled to the stator 50, and Fig. 14 is a vertical cross-sectional view showing the state in which the rotor 60 is assembled to the stator 50. Fig. 15 is a cross-sectional view showing the vertical cross-sectional configuration of the stator 50, and Fig. 16 is a cross-sectional view showing the vertical cross-sectional configuration of the rotor 60.

[0055] The stator 50 and the rotor 60 are disposed radially opposite each other with a predetermined gap (air gap) between them. The rotor 60 rotates in conjunction with the rotation of the rotary shaft 32, radially inside the annular stator 50.

[0056] 15, the portions of the stator winding 52 that are axially outward of the stator core 51 are stator coil ends SE1 and SE2. In the following description, of the stator coil ends on both axial sides, the stator coil end on one axial end side (lower side in the figure) is referred to as the "first stator coil end SE1," and the stator coil end on the other axial end side (upper side in the figure) is referred to as the "second stator coil end SE2." In addition, the space between the stator coil ends SE1 and SE2 in the axial direction is referred to as the stator coil side SS.

[0057] 16, the portions of the field winding 70 that are axially outward of the rotor core 61 are rotor coil ends RE1 and RE2. In the following description, of the rotor coil ends on both axial sides, the rotor coil end on one axial end side (lower side in the figure) is referred to as the "first rotor coil end RE1," and the rotor coil end on the other axial end side (upper side in the figure) is referred to as the "second rotor coil end RE2." Furthermore, the space between the rotor coil ends RE1 and RE2 in the axial direction is referred to as the rotor coil side RS.

[0058] 14, rotor coil ends RE1, RE2 are arranged radially inward of stator coil ends SE1, SE2. In the stator 50 and the rotor 60, the axial lengths of the stator core 51 and the rotor core 61 are the same, and the coil side portions of the stator winding 52 and the field winding 70 that overlap with the cores 51, 61 in the radial direction are the same in the axial direction.

[0059] 13, the stator winding 52 is configured by using a plurality of conductor segments 160 as conductor wires, and by connecting the segment ends 161, which are the ends of the conductor segments 160, by welding or the like. In the stator winding 52, a first stator coil end SE1 is configured by connecting the segment ends 161 on one axial side (the lower side of the figure), and a second stator coil end SE2 is configured by bending the conductor segments 160 on one axial side (the upper side of the figure).

[0060] At the first stator coil end SE1, the connection portions between the segment ends 161 are arranged at predetermined intervals in the circumferential direction. The stator 50 is configured so that a plurality of conductor segments 160 are housed radially in the slots 54 (see FIG. 3) of the stator core 51, and the plurality of segment connection portions are arranged radially.

[0061] The stator winding 52 is wound by distributed winding at a predetermined slot pitch in the circumferential direction. In this case, in the stator coil side SS (the conductor accommodation portion in the slot), the conductor materials are arranged in a plurality of layers in the radial direction, and in each stator coil end SE1, SE2, in order to avoid interference between the conductor segments 160, the conductor segments 150 are arranged in a radially dispersed state compared to the stator coil side SS. In FIG. 15, in each stator coil end SE1, SE2, the width dimension in the radial direction (the left - right direction in the figure) is larger than that of the stator coil side SS. Also, a part of the second stator coil end SE2 protrudes radially inward beyond the stator coil side SS.

[0062] In FIG. 15, in the stator winding 52, the inner diameter dimension D11 on the radially inner side of the first stator coil end SE1 and the inner diameter dimension D12 on the radially inner side of the second stator coil end SE2 are defined. In this case, the inner diameter dimension D12 of the second stator coil end SE2 is smaller than the inner diameter dimension D11 of the first stator coil end SE1 (D12 < D11). Specifically, the first stator coil end SE1 is composed of a plurality of layers of conductor segments 160 in the radial direction as described above, and the second stator coil end SE2 is provided offset radially inward compared to the first stator coil end SE1. Therefore, the inner diameter dimensions D11, D12 on the radially inner side are different between the first stator coil end SE1 side and the second stator coil end SE2 side. When comparing the outer diameter dimensions of each stator coil end SE1, SE2, the outer diameter dimension of the first stator coil end SE1 is larger than the outer diameter dimension of the second stator coil end SE2.

[0063] In comparison with the stator core 51, the inner diameter dimension D11 of the first stator coil end SE1 is larger than the inner diameter dimension D13 of the inner peripheral surface of the stator core 51. Also, the inner diameter dimension D12 of the second stator coil end SE2 is the same as or substantially the same as the inner diameter dimension D13 of the inner peripheral surface of the stator core 51.

[0064] As described above, by offsetting the stator coil end (SE2) on one axial side radially inward, the outer diameter dimension of the coil end of the stator winding 52 can be reduced, enabling the size of the stator 50. Furthermore, in the stator winding 52, the inner diameter dimensions of the stator coil ends on both axial sides are made different, and the inner diameter dimension of the stator coil end (SE1) on the other side is not made excessively small, which improves the ease of assembling the rotor 60 to the radially inner side of the stator 50.

[0065] 16, the rotor 60 has different outer peripheral surface shapes in the axial direction on the first rotor coil end RE1 side and the second rotor coil end RE2 side, with the radial dimension to the outer peripheral surface on the second rotor coil end RE2 side being narrower than on the first rotor coil end RE1 side. Here, the outer peripheral surface shape of the rotor 60 is determined by the shapes of the coil end cover 103 on the first rotor coil end RE1 side and the coil end cover 104 on the second rotor coil end RE2 side, and the shapes of these coil end covers 103, 104 (more specifically, the shapes of the annular portions 142, 152) correspond to the coil end shapes of the winding unit 110.

[0066] FIG. 17 is a side view of the winding unit 110. The winding unit 110 has the first coil module 111 on the radially outer side and the second coil module 112 on the radially inner side as described above. In a state where the winding unit 110 is assembled to the rotor core 61, the first coil module 111 defines the outer peripheral shape of the field winding 70. In this case, the outer peripheral surface on the radially outer side of the first coil module 111, that is, the insulator 122 on the outer peripheral side of the first coil module 111, has different side view shapes at one axial end side and the other axial end side. On the side of the first rotor coil end RE1 which is the lower side of the figure, the outer peripheral surface of the first coil module 111 is provided in a direction extending in the axial direction (a direction parallel to the axial direction). On the side of the second rotor coil end RE2 which is the upper side of the figure, the outer peripheral surface of the first coil module 111 is provided in a direction inclined with respect to the axial direction. In the second rotor coil end RE2, the winding unit 110 has a shape in which the outer peripheral portion is inclined with respect to the axial direction and the outer diameter dimension becomes smaller as it moves away from the rotor core 61 in the axial direction.

[0067] In FIG. 17, in the winding unit 110, the outer diameter dimension on the radially outer side at the first rotor coil end RE1 is defined as D21, and the outer diameter dimension on the radially outer side at the second rotor coil end RE2 is defined as D22. The outer diameter dimension D22 is the average value of the outer diameter dimensions in the axial direction at the second rotor coil end RE2. In other words, it can also be said that the outer diameter dimension D22 is the median value between the maximum value and the minimum value of the outer diameter dimensions at the second rotor coil end RE2. In this case, the outer diameter dimension D22 of the second rotor coil end RE2 is smaller than the outer diameter dimension D21 of the first rotor coil end RE1 (D22 < D21). In the field winding 70, due to the difference in the coil end shapes on both axial sides in each winding unit 110 arranged in the circumferential direction, the outer diameter dimensions D21 and D22 of each rotor coil end RE1 and RE2 are different from each other.

[0068] A specific winding structure in the winding unit 110 will be described below. FIGS. 18(a) and 18(b) are diagrams showing an example of a winding structure. These diagrams show the configuration of the coil body 123 of the second coil module 112. The coil body 123 is formed by concentrated winding of a conductor wire, and lane changes occur as the conductor wire is wound in multiple layers (i.e., as the conductor wire is stacked). FIG. 18 shows a lane change section L at one axial end of the coil body 123. A lane change refers to shifting the winding position in a direction intersecting the winding direction of the conductor wire when stacking the conductor wire in multiple layers. In the second coil module 112, the outer peripheral surface shape of the insulator 124 depends on the shape of the coil body 123.

[0069] 18 shows the configuration of the coil body 123 of the second coil module 112 for convenience, but the coil body 121 of the first coil module 111 has a similar configuration except for the number of turns of the conductor wire. In other words, the coil body 121 of the first coil module 111 has a lane change portion L on one of both axial ends. Of the two axial ends of the winding unit 110, the axial end having the lane change portion L is the first rotor coil end RE1.

[0070] In the winding unit 110 of each magnetic pole, at the lane change portion L where the conductor changes lanes, the conductor bulges to avoid the conductor in the lower layer. Taking this into consideration, the axial end portion of the winding unit 110 that has the lane change portion L is designated as the first rotor coil end RE1, i.e., the rotor coil end with the relatively larger outer diameter.

[0071] In the winding unit 110, ends of the conductor wires are pulled out on one axial side, and these ends of the conductor wires connect the winding units 110 together (i.e., the coil modules 111, 112). In the winding units 110 of each magnetic pole, the first coil modules 111 arranged in the circumferential direction are connected in series, and the second coil modules 112 arranged in the circumferential direction are connected in series. In this case, the first coil module 111, which is the end of the first winding section 71, and the second coil module 112, which is the end of the second winding section 72, have their ends of the conductor wires connected to electrical components mounted on the circuit module 106. In this configuration, a space for pulling out the conductor wires is required at one axial end of the winding unit 110. Therefore, it is preferable that the axial end from which the ends of the conductor wires are pulled out of both axial ends of the winding unit 110 be the first rotor coil end RE1, i.e., the rotor coil end with a relatively larger outer diameter. Furthermore, even if the winding structure of the first coil module 111 is an α-winding structure, it is preferable that the wire pull-out side of the first coil module 111 be the first rotor coil end RE1, i.e., the rotor coil end with a relatively larger outer diameter.

[0072] 14, the stator winding 52 and the field winding 70 are respectively arranged such that the first stator coil end SE1 and the first rotor coil end RE1 are aligned radially, and the second stator coil end SE2 and the second rotor coil end RE2 are aligned radially. In this case, the stator winding 52 and the field winding 70 are respectively arranged such that the first stator coil end SE1, which has a relatively large inner diameter, and the first rotor coil end RE1, which has a relatively large outer diameter, are aligned radially, and the second stator coil end SE2, which has a relatively small inner diameter, and the second rotor coil end RE2, which has a relatively small outer diameter, are aligned radially. This reduces interference between the stator winding 52 and members on the rotor 60 side (particularly the coil end covers 103, 104).

[0073] Furthermore, when manufacturing the rotating electric machine 40, the rotor 60 is assembled axially into the hollow portion of the stator 50. At this time, the rotor 60 is assembled into the stator 50 from the first stator coil end SE1 side (the lower side in FIG. 14 ). Furthermore, the second rotor coil end RE2 of the rotor 60 is the leading side when assembled into the stator 50. This prevents interference between the stator 50 and the rotor 60, and allows the rotor 60 to be assembled easily into the stator 50.

[0074] FIG. 19 is an enlarged longitudinal cross-sectional view showing a portion where the second stator coil end SE2 and the second rotor coil end RE2 are arranged side by side.

[0075] 19, in the second rotor coil end RE2, the outer peripheral surface on the radially outer side is inclined with respect to the axial direction (see Q1 in the figure), and the outer diameter dimension becomes smaller as it becomes axially farther away from the rotor core 61. In addition, the annular portion 152 of the coil end cover 104 has a outer peripheral surface on the radially outer side inclined with respect to the axial direction (see Q2 in the figure), and the outer diameter dimension becomes smaller as it becomes axially farther away from the rotor core 61.

[0076] The second stator coil end SE2 and the annular portion 152 of the coil end cover 104 face each other in the radial direction. The gap dimension between the second stator coil end SE2 and the annular portion 152 increases as the distance from the rotor core 61 increases in the axial direction.

[0077] Furthermore, the radial gap dimension G1 between the second stator coil end SE2 and the annular portion 152 of the coil end cover 104 is larger than the radial gap dimension G2 between the stator 50 and the outer circumferential covering portion 102 on the stator coil side SS (axially between the first stator coil end SE1 and the second stator coil end SE2). The gap dimension G1 between the second stator coil end SE2 and the annular portion 152 is preferably the average value of the separation distance between the second stator coil end SE2 and the annular portion 152 as viewed in the axial direction.

[0078] According to the present embodiment described above in detail, the following excellent effects can be obtained.

[0079] In the rotating electric machine 40, the stator winding 52 and the field winding 70 are arranged so that the first stator coil end SE1, which has a relatively large inner diameter, and the first rotor coil end RE1, which has a relatively large outer diameter, are aligned radially, and the second stator coil end SE2, which has a relatively small inner diameter, and the second rotor coil end RE2, which has a relatively small outer diameter, are aligned radially. This improves the ease of assembly of the stator 50 and the rotor 60. As a result, the stator 50 and the rotor 60 can be positioned radially opposite each other in an appropriate state.

[0080] In the winding unit 110 of each magnetic pole, at the lane change portion L where the conductor changes lanes, the conductor bulges to avoid the conductor in the lower layer. In consideration of this, the axial end of the winding unit 110 that has the lane change portion L is designated as the first rotor coil end RE1 (i.e., the rotor coil end that has a relatively large outer diameter and is aligned radially with the first stator coil end SE1 that has a relatively large inner diameter). This allows the conductor to be properly wound in the winding unit 110 while suitably suppressing interference between the stator 50 and the rotor 60.

[0081] In a configuration in which the winding unit 110 (coil modules 111, 112) and the circuit module 106 are connected, the ends of the conductor wires (conductor end portions) are drawn out in the axial direction from the winding unit 110. In this case, of the two axial ends of the winding unit 110, the axial end portion closest to the conductor end portion is the first rotor coil end RE1 (i.e., the rotor coil end that has a relatively large outer diameter and is aligned radially with the first stator coil end SE1 that has a relatively large inner diameter). This allows the circuit module 106 to be properly positioned in the rotor 60, while suitably suppressing interference between the stator 50 and the rotor 60.

[0082] In the stator winding 52, a portion of the second stator coil end SE2, which has a smaller inner diameter, protrudes radially inward from the stator coil side SS, while in the field winding 70, in the second rotor coil end RE2, the outer diameter of each winding unit 110 decreases the further it is axially away from the rotor core 61. In this case, interference between the second stator coil end SE2 and the second rotor coil end RE2 can be avoided without reducing the conductor space factor in the field winding 70.

[0083] In the coil end cover 104, the outer peripheral surface of the annular portion 152 is inclined relative to the axial direction, and the outer diameter dimension becomes smaller the further away from the rotor core 61 in the axial direction. In other words, in the coil end cover 104, the outer peripheral surface of the annular portion 152 that faces the second stator coil end SE2 of the stator winding 52 in the radial direction is inclined in the same direction as the second rotor coil end RE2. This allows an appropriate gap to be formed between the stator winding 52 and the coil end cover 104 on the rotor 60 side.

[0084] The second stator coil end SE2 and the annular portion 152 of the coil end cover 104 are radially opposed to each other, and the gap dimension between the second stator coil end SE2 and the annular portion 152 increases axially as the distance from the rotor core 61 increases. In this case, there is a greater concern about displacement or deformation of the field winding 70 at the axial tip end side of the second stator coil end SE2 than at the base end side (rotor core side); however, with the above configuration, interference between the second stator coil end SE2 and the coil end cover 104 can be suitably suppressed.

[0085] The radial gap dimension G1 (average separation distance) between the second stator coil end SE2 and the annular portion 152 of the coil end cover 104 is made larger than the radial gap dimension G2 between the stator core 51 and the outer circumferential covering portion 102. In this case, in the stator winding 52, the second stator coil end SE2, which is radially outer than the stator core 51, is more likely to be displaced or deformed than the stator core side, but the above configuration makes it possible to suitably suppress interference between the second stator coil end SE2 and the coil end cover 104.

[0086] (Other embodiments) The above embodiment may be modified as follows, for example.

[0087] In the above embodiment, the winding unit 110 of the field winding 70 is configured by two coil modules 111, 112, one radially inner and one radially outer, but this configuration may be changed. The field winding 70 may be configured by a single coil module rather than being divided into two radially inner and outer coil modules 111, 112.

[0088] In the above embodiment, the pole coils of the magnetic poles are each formed by a winding unit 110, but this may be modified. For example, the pole coils of the magnetic poles may be formed by continuously winding a conductive wire around each of the magnetic poles arranged in the circumferential direction.

[0089] In the stator 50, the stator core may not be provided with teeth.

[0090] 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.

[0091] The moving body on which the rotating electric machine system is mounted is not limited to a vehicle, but may be, for example, an aircraft or a ship. Furthermore, the rotating electric machine system is not limited to a system mounted on a moving body, but may be a stationary system.

[0092] The technical ideas extracted from the above-described embodiments will be described below. [Configuration 1] a stator (50) having stator windings (52); a rotor (60) having a rotor core (61) including a plurality of main pole portions (62) provided for each of the magnetic poles arranged in the circumferential direction, and a field winding (70) wound around each of the main pole portions; a rotor disposed radially inside the stator to face the rotor, the stator winding has a first stator coil end (SE1) at one axial end and a second stator coil end (SE2) at the other axial end, and the inner diameter dimension of the radially inner side of the second stator coil end is smaller than the inner diameter dimension of the radially inner side of the first stator coil end, the field winding includes a plurality of pole coils (110) provided for each magnetic pole, and has a first rotor coil end (RE1) on one axial end side and a second rotor coil end (RE2) on the other axial end side, the outer diameter dimension of the second rotor coil end on the radial outside being smaller than the outer diameter dimension of the first rotor coil end on the radial outside, a wound-field rotating electric machine, in which the stator winding and the field winding are respectively arranged so that the first stator coil end and the first rotor coil end are aligned in the radial direction, and the second stator coil end and the second rotor coil end are aligned in the radial direction. [Configuration 2] In the field winding, each pole coil is formed by winding a conductor material by concentrated winding, and has a lane change portion (L) at one of both axial ends where a lane change occurs as the conductor material is laminated, 2. The wound-field rotating electric machine according to configuration 1, wherein the pole coil has an axial end having the lane change portion among both axial ends thereof, which is the first rotor coil end. [Configuration 3] the rotor includes a circuit module (106) disposed on one axial end side of the rotor core and including electrical components connected to the field winding; Each of the pole coils has an axially extending conductor end connected to the circuit module; 3. The wound-field rotating electric machine according to configuration 1 or 2, wherein the axial end of the pole coil that is closer to the conductor end is the first rotor coil end. [Configuration 4] the stator winding has a stator coil side (SS) between the first stator coil end and the second stator coil end in the axial direction, and a portion of the second stator coil end protrudes radially inward beyond the stator coil side, 4. The wound-field rotating electric machine according to any one of configurations 1 to 3, wherein, at the second rotor coil end, the outer periphery of each pole coil is inclined with respect to the axial direction, and the outer diameter dimension becomes smaller as it gets farther away from the rotor core in the axial direction. [Configuration 5] The rotor has a coil end cover (104) provided to cover the second rotor coil end, the coil end cover has an end plate portion (151) that faces the second rotor coil end in the axial direction, and an annular portion (152) that extends in the axial direction from an outer periphery of the end plate portion and surrounds the second rotor coil end, A wound-field rotating electric machine according to configuration 4, wherein the annular portion has an outer peripheral surface on the radially outer side that is inclined with respect to the axial direction, and the outer diameter dimension becomes smaller as it moves away from the rotor core in the axial direction. [Configuration 6] 6. The wound-field rotating electric machine according to configuration 5, wherein the second stator coil end and the annular portion of the coil end cover face each other in the radial direction, and the gap dimension between the second stator coil end and the annular portion increases with increasing distance from the rotor core in the axial direction. [Configuration 7] The rotor is a coil end cover (104) provided to cover the second rotor coil end; an outer circumferential covering portion (102) provided so as to surround each of the main pole portions and the field winding from the radially outer side in a rotor coil side (RS) between the first rotor coil end and the second rotor coil end in the axial direction; and the coil end cover has an end plate portion (151) that faces the second rotor coil end in the axial direction, and an annular portion (152) that extends in the axial direction from an outer periphery of the end plate portion and surrounds the second rotor coil end, 7. The wound-field rotating electric machine according to any one of configurations 1 to 6, wherein a radial gap dimension between the second stator coil end and the annular portion of the coil end cover is larger than a radial gap dimension between the stator and the outer circumferential covering portion between the first stator coil end and the second stator coil end in the axial direction. [Explanation of symbols]

[0093] 40... rotating electric machine, 50... stator, 52... stator winding, 60... rotor, 61... rotor core, 62... main pole portion, 70... field winding, 110... winding unit, SE1... first stator coil end, SE2... second stator coil end, RE1... first rotor coil end, RE2... second rotor coil end.

Claims

1. a stator (50) having stator windings (52); a rotor (60) having a rotor core (61) including a plurality of main pole portions (62) provided for each of the magnetic poles arranged in the circumferential direction, and a field winding (70) wound around each of the main pole portions; a rotor disposed radially inside the stator to face the rotor, the stator winding has a first stator coil end (SE1) at one axial end and a second stator coil end (SE2) at the other axial end, and the inner diameter dimension of the radially inner side of the second stator coil end is smaller than the inner diameter dimension of the radially inner side of the first stator coil end, the field winding includes a plurality of pole coils (110) provided for each magnetic pole, and has a first rotor coil end (RE1) at one axial end and a second rotor coil end (RE2) at the other axial end, the outer diameter dimension of the second rotor coil end on the radial outside being smaller than the outer diameter dimension of the first rotor coil end on the radial outside, a wound-field rotating electric machine, wherein the stator winding and the field winding are respectively arranged so that the first stator coil end and the first rotor coil end are aligned in the radial direction, and the second stator coil end and the second rotor coil end are aligned in the radial direction.

2. In the field winding, each pole coil is formed by winding a conductor material by concentrated winding, and has a lane change portion (L) at either one of both axial ends where a lane change occurs as the conductor material is laminated, 2. The wound-field rotating electric machine according to claim 1, wherein the axial end of the pole coil having the lane change portion is the first rotor coil end.

3. the rotor includes a circuit module (106) disposed on one axial end side of the rotor core and including electrical components connected to the field winding; Each of the pole coils has an axially extending conductor end connected to the circuit module; 2. The wound-field rotating electric machine according to claim 1, wherein the axial end of the pole coil that is closer to the conductor end is the first rotor coil end.

4. the stator winding has a stator coil side (SS) between the first stator coil end and the second stator coil end in the axial direction, and a portion of the second stator coil end protrudes radially inward beyond the stator coil side, 4. The wound-field rotating electric machine according to claim 1, wherein the outer periphery of each pole coil at the second rotor coil end is inclined with respect to the axial direction, and the outer diameter dimension of each pole coil becomes smaller as it is further away from the rotor core in the axial direction.

5. The rotor has a coil end cover (104) provided to cover the second rotor coil end, The coil end cover has an end plate portion (151) that faces the second rotor coil end in the axial direction, and an annular portion (152) that extends in the axial direction from an outer periphery of the end plate portion and surrounds the second rotor coil end, 5. The wound-field rotating electric machine according to claim 4, wherein the annular portion has an outer peripheral surface on the radially outer side that is inclined with respect to the axial direction, and an outer diameter dimension of the annular portion decreases as it moves away from the rotor core in the axial direction.

6. 6. The wound-field rotating electric machine according to claim 5, wherein the second stator coil end and the annular portion of the coil end cover face each other in a radial direction, and the dimension of a gap between the second stator coil end and the annular portion increases with increasing axial distance from the rotor core.

7. The rotor is a coil end cover (104) provided to cover the second rotor coil end; an outer circumferential covering portion (102) provided so as to surround each of the main pole portions and the field winding from the radially outer side in a rotor coil side (RS) between the first rotor coil end and the second rotor coil end in the axial direction; and The coil end cover has an end plate portion (151) that faces the second rotor coil end in the axial direction, and an annular portion (152) that extends in the axial direction from an outer periphery of the end plate portion and surrounds the second rotor coil end, 4. The wound-field rotating electric machine according to claim 1, wherein a radial gap dimension between the second stator coil end and the annular portion of the coil end cover is larger than a radial gap dimension between the stator and the outer peripheral covering portion in the axial direction between the first stator coil end and the second stator coil end.

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