Winding excitation type rotating electric machine

Abstract

In a winding excitation-type rotating electrical machine, a rotor (60) has a rotor core (61) having main pole sections (62) which are provided to each of magnetic poles arranged in the circumferential direction and which protrude in the radial direction, and excitation windings wound around the main pole sections. The field winding has a series connection body of a first winding part (a first coil component (111)) and a second winding part (a second coil component (112)), the first winding part is positioned on the side close to the stator in the radial direction, the second winding part is positioned on the side away from the stator, and the winding parts are wound around the main pole parts. The first winding portion constitutes a series resonance circuit by being connected in series with the capacitor, and the second winding portion constitutes a parallel resonance circuit by being connected in parallel with the capacitor. The number of turns of the second winding part is larger than the number of turns of the first winding part, and the conductor cross-sectional area of the wire material for the second winding part is smaller than the conductor cross-sectional area of the wire material for the first winding part.

Description

[0001] Cross Reference to Related Applications

[0002] This application is based on Japanese Patent Application No. 2023-118124 filed July 20, 2023, the contents of which are incorporated herein by reference. TECHNICAL FIELD

[0003] The disclosure in this specification relates to a wound-field type rotary electric machine. BACKGROUND

[0004] As such a wound-field type rotary electric machine, there is known, for example, the rotary electric machine described in Patent Literature 1. In this rotary electric machine, in a rotor, a field winding is wound around a main pole portion (magnetic salient pole portion) of each magnetic pole arranged in the circumferential direction, and a field current is induced in the field winding by a high-order harmonic current flowing through a winding (stator winding) of a stator arranged opposite to the rotor. In addition, the field winding has a series connection body of a first winding portion and a second winding portion, the first winding portion is located on the side close to the stator in the radial direction, the second winding portion is located on the side away from the stator, these winding portions are wound around the main pole portion, and a series resonance circuit is constituted by the first winding portion and a capacitor, and a parallel resonance circuit is constituted by the second winding portion and the capacitor. In this case, it is preferable that the number of turns of wire of the second winding portion is more than the number of turns of wire of the first winding portion.

[0005] Prior Art Documents

[0006] Patent Literature

[0007] Patent Literature 1: Japanese Patent Application Publication No. 2020-54064

[0008] In the wound-field type rotary electric machine of the above-described structure, in the case where the number of turns of wire of the second winding portion is more than the number of turns of wire of the first winding portion, the current value (current effective value) of the second winding portion is smaller than the current value of the first winding portion. In this case, in the structure in which the same conductor cross-sectional area wire material is used as the wire material of the first winding portion and the second winding portion, although the current flowing through the second winding portion is relatively small, the conductor cross-sectional area is excessively large. Therefore, the number of turns of the second winding portion is unnecessarily limited, and there is a concern that this causes a limitation of the field current. SUMMARY

[0009] The present disclosure was completed in view of the above-described circumstances, and aims to provide a wound-field type rotary electric machine capable of achieving an increase in the field current flowing through the field winding.

[0010] The present disclosure relates to a wound-field type rotary electric machine, comprising:

[0011] a stator having a stator winding; and

[0012] a rotor having a rotor core having a main pole portion provided to each magnetic pole arranged in a circumferential direction and protruding in a radial direction, and an exciting winding wound around the main pole portion,

[0013] a high frequency current for causing the exciting winding to induce an exciting current to flow through the stator winding,

[0014] the exciting winding has a series connection body of a first winding portion and a second winding portion, the first winding portion is located on a side close to the stator in a radial direction, the second winding portion is located on a side away from the stator, and each of the winding portions is wound around each of the main pole portions,

[0015] the first winding portion forms a series resonance circuit by being connected in series with a capacitor, and the second winding portion forms a parallel resonance circuit by being connected in parallel with the capacitor,

[0016] the number of turns of the second winding portion is larger than the number of turns of the first winding portion, and the conductor cross-sectional area of a wire material for the second winding portion is smaller than the conductor cross-sectional area of a wire material for the first winding portion.

[0017] In a rotor of a winding-excited rotary electric machine, a structure is considered in which a series connection body of a first winding portion and a second winding portion is provided as an exciting winding, a series resonance circuit and a parallel resonance circuit are formed by each of the winding portions and a capacitor, and the number of turns of the second winding portion located on a side away from a stator in a radial direction is larger than the number of turns of the first winding portion located on a side close to the stator. In this case, by making the number of turns of the second winding portion larger than the number of turns of the first winding portion, the inductance of the second winding portion increases, and the exciting current can be increased. Here, in the structure in which the number of turns of the second winding portion is made larger than the number of turns of the first winding portion, the current value (current effective value) of the second winding portion is smaller than the current value of the first winding portion, in other words, the current that can be passed in the second winding portion is a current that is smaller than that of the first winding portion.

[0018] In view of this, the conductor cross-sectional area of a wire material for the second winding portion is made smaller than the conductor cross-sectional area of a wire material for the first winding portion. Thereby, compared to a case in which the same conductor cross-sectional area of a wire material is used in the first winding portion and the second winding portion, the number of turns in the second winding portion can be increased. As a result, an increase in the exciting current flowing through the exciting winding can be achieved. BRIEF DESCRIPTION OF DRAWINGS

[0019] The above objects, as well as other objects, features or advantages of the present disclosure will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. The drawings are as follows:

[0020] Figure 1 is a whole configuration view of a control system of a rotary electric machine,

[0021] Figure 2 is a diagram showing an inverter and its peripheral structure,

[0022] Figure 3 is a cross-sectional view of a rotor and a stator,

[0023] Figure 4 is a diagram showing an electric circuit provided to a rotor,

[0024] Figure 5 is a perspective view showing an overall structure of a rotor,

[0025] Figure 6 is an exploded perspective view of a rotor,

[0026] Figure 7 is a longitudinal cross-sectional view of a rotor,

[0027] Figure 8 is a perspective view showing a winding unit in a rotor main portion,

[0028] Figure 9 is a cross-sectional view of a rotor main portion,

[0029] Figure 10 is a cross-sectional view schematically showing each wire of a first winding portion and a second winding portion,

[0030] Figure 11 is a diagram showing a state in which a winding portion is wound around each main pole portion of a rotor core,

[0031] Figure 12 is a perspective view showing a structure related to connection of a coil body in each winding portion,

[0032] Figure 13 is an electric circuit diagram of a rotor,

[0033] Figure 14 is a cross-sectional view of a wire,

[0034] Figure 15 is a longitudinal cross-sectional view showing a state in which wire end portions of a coil body are joined to each other in a component holder,

[0035] Figure 16 is a cross-sectional view schematically showing each wire of a first winding portion and a second winding portion. DETAILED DESCRIPTION

[0036] Hereinafter, one embodiment of a rotating electric machine to which the present disclosure is applied will be described with reference to the drawings. The rotating electric machine is used as a running power source in an electric vehicle such as an electric automobile or a hybrid automobile, for example.

[0037] First, a configuration of a rotating electric machine 1 will be described with reference to FIG. 1. The rotating electric machine 1 is a three-phase alternating-current motor. The rotating electric machine 1 is used as a running power source in an electric automobile, for example. Figure 1The control system for the rotating electric motor is described below. The control system includes a DC power supply 10, an inverter 20, a control device 30, and a rotating electric motor 40. The rotating electric motor 40 is a winding-excited synchronous machine. For example, the rotating electric motor 40, the inverter 20, and the control device 30 can be configured as an electromechanical integrated drive device, or they can be configured as separate components.

[0038] The rotary electric motor 40 includes a housing 41 and a stator 50 and a rotor 60 housed within the housing 41. The rotary electric motor 40 of this embodiment is an inner rotor type rotary electric motor in which the rotor 60 is arranged radially inward of the stator 50. The stator 50 includes a stator core 51 and stator windings 52. The stator windings 52 are made of copper wire, for example, and include U, V, and W phase windings 52U, 52V, and 52W arranged with electrical angles offset from each other by 120°. The rotor 60 includes a rotor core 61 and an excitation winding 70. A rotating shaft 32 is assembled in the central hole of the rotor core 61. The rotating shaft 32 is rotatably supported in the housing 41 by bearings 42 and 43.

[0039] like Figure 2 As shown, the inverter 20 has a series connection of the upper arm switches SUP, SVP, SWP for phases U, V, and W, and the lower arm switches SUn, SVn, SWn for phases U, V, and W. In each phase, the first end of the U, V, and W phase windings 52U, 52V, and 52W is connected to the connection point of the upper arm switches SUP, SVP, SWp and the lower arm switches SUn, SVn, SWn. The second end of the U, V, and W phase windings 52U, 52V, and 52W is connected through the neutral point. That is, in this embodiment, the stator winding 52 is star-connected. However, the stator winding 52 can also be delta-connected. In this embodiment, each switch SUP to SWn is an IGBT. In each switch SUP to SWn, the freewheeling diode is connected in anti-parallel.

[0040] The collectors of the upper arm switches SUP, SVP, and SWP of each phase are connected to the positive terminal of the DC power supply 10. The emitters of the lower arm switches SUn, SVn, and SWn of each phase are connected to the negative terminal of the DC power supply 10. In addition, the DC power supply 10 is connected in parallel with the smoothing capacitor 11.

[0041] Next, use Figure 3 The stator 50 and rotor 60 are described below.

[0042] Both the stator 50 and the rotor 60 are coaxially arranged together with the rotating shaft 32. In the following description, the direction of extension of the rotating shaft 32 is defined as axial, the direction of radial extension from the center of the rotating shaft 32 is defined as radial, and the direction of circumferential extension from the rotating shaft 32 is defined as circumferential.

[0043] The stator core 51 is composed of laminated steel sheets formed of a soft magnetic material, has a back yoke 51a in a circular ring shape, and a plurality of teeth 51b protruding from the back yoke 51a toward the radial inner side. A plurality of slots 54 arranged in the circumferential direction are formed between adjacent teeth 51b. The stator winding 52 is composed by housing phase windings of each phase in the respective slots 54 in a prescribed order. For example, in the stator 50, a segment coil structure using a plurality of conductor segments can also be employed. However, the structure of the stator winding 52 is arbitrary.

[0044] The rotor core 61 is formed of a soft magnetic material, for example, by laminated steel sheets. The rotor core 61 has a cylindrical portion 61a in a cylindrical shape, and a plurality of main pole portions 62 protruding from the cylindrical portion 61a toward the radial outer side. The field winding 70 is wound on the main pole portions 62 by concentrated winding. In the present embodiment, eight main pole portions 62 are provided at equal intervals in the circumferential direction.

[0045] The field winding 70 has a first winding portion 71a and a second winding portion 71b. In each main pole portion 62, the first winding portion 71a is wound on the radial outer side, and the second winding portion 71b is wound on a position more radially inward than the first winding portion 71a. In terms of the relationship with the stator 50, in the radial direction, the first winding portion 71a is wound on the side close to the stator 50, and the second winding portion 71b is wound on the side away from the stator 50. In each main pole portion 62, the winding directions of the first winding portion 71a and the second winding portion 71b are the same as each other. In addition, the winding directions of the respective winding portions 71a, 71b wound on one of the main pole portions 62 adjacent in the circumferential direction are opposite to the winding directions of the respective winding portions 71a, 71b wound on the other main pole portion. Therefore, the main pole portions 62 adjacent in the circumferential direction have opposite magnetization directions to each other. By each main pole portion 62 in the rotor core 61 and the field winding 70 wound on the same, a plurality of magnetic poles (field poles) arranged in the circumferential direction are formed in the rotor 60.

[0046] Figure 4 A power circuit on the rotor 60 side provided with the respective winding portions 71a, 71b wound on the main pole portions 62 is shown. The first winding portion 71a and the second winding portion 71b are connected in series, and a capacitor portion CC composed of a plurality of first capacitors 91 is connected in parallel to the second winding portion 71b. The capacitor portion CC is composed as a parallel connection body of the plurality of first capacitors 91. In addition, a second capacitor 92 is connected in parallel to the series connection body of the first winding portion 71a and the second winding portion 71b. The second capacitor 92 is provided to suppress noise. The first capacitor 91 and the second capacitor 92 are, for example, laminated ceramic capacitors, and are the same structure as each other.

[0047] A diode 93 as a rectifying element is connected between both ends of the series connection body composed of the respective winding portions 71a, 71b. That is, the first end of the first winding portion 71a is connected to the cathode of the diode 93, and the first end of the second winding portion 71b is connected to the second end of the first winding portion 71a. The anode of the diode 93 is connected to the second end of the second winding portion 71b.

[0048] In the present embodiment, a series resonant circuit is composed of the first winding portion 71a, the first capacitor 91, and the diode 93, and a parallel resonant circuit is composed of the second winding portion 71b and the first capacitor 91. In this case, the first winding portion 71a is connected in series to the first capacitor 91, and the second winding portion 71b is connected in parallel to the first capacitor 91. When the resonant frequency of the series resonant circuit, that is, the first resonant frequency is set to fl, and the resonant frequency of the parallel resonant circuit, that is, the second resonant frequency is set to f2, these respective resonant frequencies fl, f2 are expressed by the following equations (1), (2). Ll is the inductance of the first winding portion 71a, L2 is the inductance of the second winding portion 71b, and C is the electrostatic capacity of the first capacitor 91.

[0049]

[0050] When the high-frequency exciting current flows through the stator winding 52, a variation due to the high-frequency component of the main magnetic flux occurs in the magnetic circuit including the stator core 51 and the rotor core 61. Due to the occurrence of the variation of the main magnetic flux, an induced voltage is generated in each winding portion 71a, 71b, and an induced current is generated in each winding portion 71a, 71b. At this time, in the case where the induced voltages of the same polarity are generated in each winding portion 71a, 71b, the induced currents of each winding portion 71a, 71b are not canceled, and thus the induced current increases. The current flowing to each winding portion 71a, 71b is rectified to one direction by the diode 93. Thereby, the exciting current flows to the exciting winding 70 in the direction rectified by the diode 93, and the exciting winding 70 is excited.

[0051] Returning to Figure 2 The control device 30 is composed of a microcomputer (corresponding to a computer) as a main body, and the microcomputer has a CPU. The control device 30 generates a drive signal that turns on and off each switch SUp to SWn that constitutes the inverter 20. In detail, the control device 30 converts the direct-current electric power output from the direct-current power source 10 into alternating-current electric power, and generates a drive signal that turns on and off each switch SUp to SWn that should supply the U, V, W phase windings 52U, 52V, 52W, and supplies the generated drive signal to the gate of each switch SUp to SWn.

[0052] The control device 30 turns on and off each switch SUp to SWn to cause a resultant current of the fundamental current and the high-frequency exciting current to flow to each phase winding 52U, 52V, 52W. The fundamental current is a current that mainly causes the rotating electric machine 40 to generate torque. The high-frequency exciting current is a high-frequency current that is higher in frequency than the fundamental current, and is a current that mainly excites the exciting winding 70. As the high-frequency current, a high-order harmonic current can be used. The electrical angles of the phase currents flowing to each phase winding 52U, 52V, 52W are each shifted by 120°.

[0053] Next, the structure of the rotor 60 is described in more detail. Figure 5 is a perspective view that shows the overall structure of the rotor 60, Figure 6 is an exploded perspective view of the rotor 60, Figure 7 is a longitudinal sectional view of the rotor 60.

[0054] The rotor 60 generally has a rotor main portion 101, a circuit assembly 102 provided at one end side of the axial direction of the rotor main portion 101, and coil end covers 103, 104 as circular ring members installed at the one end side and the other end side of the axial direction of the rotor main portion 101. As shown by Figure 3 As described above, the rotor main portion 101 is provided with the rotor core 61 and the exciting winding 70, and the rotating shaft 32 is assembled in the central hole of the rotor core 61. The exciting winding 70 is composed of a plurality of winding units 110 arranged in the circumferential direction.

[0055] The circuit assembly 102 is fixed to the rotating shaft 32 in a state in which the rotating shaft 32 is inserted through the hollow portion. The circuit assembly 102 is provided at a position that is axially opposite to the coil end portion of the exciting winding 70. The circuit assembly 102 is an electric circuit portion that is provided with each capacitor 91, 92, a diode 93, and a bus bar or the like that electrically connects these elements. Figure 4 As described above, the rotor main portion 101 is provided with the rotor core 61 and the exciting winding 70, and the rotating shaft 32 is assembled in the central hole of the rotor core 61. The exciting winding 70 is composed of a plurality of winding units 110 arranged in the circumferential direction.

[0056] Figure 8 is a perspective view that shows the winding unit 110 in the rotor main portion 101, Figure 9 is a cross-sectional view that shows a cross-sectional structure with respect to a portion of the rotor main portion 101. The rotor main portion 101 has a plurality of winding units 110 provided for each magnetic pole of the rotor 60. Each winding unit 110 is formed in a ring shape with the axial direction as the long side direction, and is assembled to the rotor core 61 in a state in which the hollow portion of each winding unit 110 is inserted through the main pole portion 62 of the rotor core 61.

[0057] The winding unit 110 has a first coil assembly 111 that becomes the radially outer side in the installed state to the main pole portion 62, and a second coil assembly 112 that becomes the radially inner side. The first coil assembly 111 is a coil assembly that corresponds to the first winding portion 71a, and the second coil assembly 112 is a coil assembly that corresponds to the second winding portion 71b.

[0058] The first coil assembly 111 has a coil body 121 formed by winding a conductor wire made of a flat wire in multiple layers in the circumferential direction and the radial direction of the rotor 60, and an insulator 122 provided integrally with the coil body 121, which is thin plate-shaped. The insulator 122 has a portion extending in the circumferential direction and covering the radial outer side and the radial inner side of the coil body 121, and a portion extending in the radial direction and covering the hollow portion of the coil body 121. That is, in the coil body 121, the radial inner and outer portions and the portion on the inner circumferential side opposite the main pole portion 62 are covered with the insulator 122.

[0059] The second coil assembly 112 has a coil body 123 formed by winding a conductor wire made of a flat wire in multiple layers in the circumferential direction and the radial direction of the rotor 60, and an insulator 124 provided integrally with the coil body 123, which is thin plate-shaped. The insulator 124 has a portion extending in the circumferential direction and covering the radial outer side and the radial inner side of the coil body 123, and a portion extending in the radial direction and covering the hollow portion of the coil body 123. That is, in the coil body 123, the radial inner and outer portions and the portion on the inner circumferential side opposite the main pole portion 62 are covered with the insulator 124.

[0060] The coil bodies 121, 123 are configured as α wound coils, for example, are hollow coils in which the conductor wire is wound in a manner that it becomes multiple layers in the direction of the overlapping of the loops (the circumferential direction of the rotor) and two layers in the direction of the extension of the hollow portion (the radial direction of the rotor). In the present embodiment, as the conductor wire of the coil bodies 121, 123, a flat conductor wire having a rectangular shape with a long side and a short side is used. The coil bodies 121, 123 are wound in a direction in which the long side portions are overlapped in multiple layers by the loops of the conductor wire. The flat wire is composed of a conductor made of aluminum or the like and an insulating layer covering the conductor.

[0061] In the first coil assembly 111, two conductor wire end portions 125 are drawn out in the axial direction from one coil body 121. In the second coil assembly 112, a total of six conductor wire end portions 126 are drawn out in the axial direction from the three coil bodies 123 arranged in the radial direction.

[0062] As Figure 9In the first coil assembly 111, the wire material is wound in two layers in the radial direction, and in the second coil assembly 112, the wire material is wound in six layers in the radial direction. In the case of the coil bodies 121, 123, one coil body 121 is provided in the radial direction in the first coil assembly 111, and three coil bodies 123 are provided in the radial direction in the second coil assembly 112. In this case, the number of turns of the second winding portion 71b in each main pole portion 62 is greater than the number of turns of the first winding portion 71a. Furthermore, in each coil assembly 111, 112, the number of windings in the circumferential direction (in other words, the number of arrangements of the wire material in the circumferential direction) differs, and the number of windings on the radially outer side is greater than the number of windings on the radially inner side. As a result, an increase in the space factor in the field winding 70 is achieved.

[0063] In addition, in the rotor main portion 101, holding plates 127, 128 are provided between the main pole portions 62 of the rotor core 61, and these holding plates 127, 128 hold the assembled state of the first coil assembly 111 and the second coil assembly 112 in a state in which these coil assemblies 111, 112 are assembled to each main pole portion 62. The holding plate 127 is attached to the radially outer side of the first coil assembly 111, and the holding plate 128 is attached between the first coil assembly 111 and the second coil assembly 112.

[0064] Furthermore, as Figure 6 As shown, the rotor 60 has a coil end ring 81 that is assembled to the axial end portion of the winding unit 110. As Figure 7 As shown, the coil end ring 81 is provided between the coil end portion of the first coil assembly 111 and the coil end portion of the second coil assembly 112 in the radial direction, and is provided in a state in which it is sandwiched between the holding plate 128 and the coil end cover 103 in the axial direction.

[0065] However, in the rotor 60 of the winding field type in the present embodiment, a structure is adopted in which series resonance circuits and parallel resonance circuits are formed by each winding portion 71a, 71b that is the field winding 70 and the first capacitor 91, and the number of turns of the radially inner second winding portion 71b is greater than the number of turns of the radially outer first winding portion 71a. In this case, by making the number of turns of the second winding portion 71b greater than the number of turns of the first winding portion 71a, the inductance of the second winding portion 71b increases, and the field current can be increased. Here, in the structure in which the number of turns of the second winding portion 71b is made greater than the number of turns of the first winding portion 71a, the current value (current effective value) of the second winding portion 71b is smaller than the current value of the first winding portion 71a, in other words, the current that can be passed through the second winding portion 71b is a current that is smaller than the first winding portion 71a.

[0066] In view of this, in this embodiment, the conductor cross-sectional area of ​​the wire used for the second winding section 71b is smaller than the conductor cross-sectional area of ​​the wire used for the first winding section 71a. Hereinafter, features related to the winding structure of the excitation winding 70 will be described.

[0067] Figure 10 This is a schematic cross-sectional view showing the conductors C1 and C2 of the first winding section 71a and the second winding section 71b. Figure 10 In the figure, when wound around the main pole portion 62, a coil body 121 of a first winding portion 71a and a coil body 123 of a second winding portion 71b are shown respectively. The vertical direction of the figure is radial, and the horizontal direction of the figure is circumferential.

[0068] like Figure 10 As shown, the cross-sectional areas, i.e., conductor cross-sectional areas, of the conductor C1 in coil body 121 (first winding section 71a) and the conductor C2 in coil body 123 (second winding section 71b) are different, with the conductor cross-sectional area of ​​conductor C2 being smaller than that of conductor C1. More specifically, when the lengths of the long and short sides of conductor C1 are set to D1 and D2, and the lengths of the long and short sides of conductor C2 are set to D3 and D4, these lengths are related as D1 = D3 and D2 > D4. That is, the length of the long side of conductor C2 is the same as that of conductor C1, while the length of the short side is smaller. In this case, compared to the case where conductors with the same conductor cross-sectional area are used in the first winding section 71a and the second winding section 71b, the number of turns in the second winding section 71b can be increased.

[0069] In addition, such as Figure 9 As shown, in the rotor core 61, the winding space for the conductor is formed between adjacent main pole portions 62 in the circumferential direction. Viewed radially, the winding space becomes relatively narrower on the radially inner side. In this respect, since the conductor cross-sectional area of ​​the conductor C2 in the second winding portion 71b is smaller than that of the conductor cross-sectional area of ​​the conductor C1 in the first winding portion 71a, the number of turns of the conductor C2 can be ensured even in the relatively narrow winding space.

[0070] Figure 11 This is a schematic diagram showing the state in which the winding sections 71a and 71b are wound onto the main pole sections 62 of the rotor core 61. Figure 11In the present embodiment, the two layers of conductors on the radially outer side are the first winding portion 71a, and the four layers of conductors on the radially inner side are the second winding portion 71b. The first winding portion 71a is configured by assembling the coil bodies 121 to the respective main pole portions 62 arranged in the circumferential direction, and connecting the coil bodies 121 in series. Here, the respective coil bodies 121 that configure the first winding portion 71a are Cll, C12, C13,... C18 in that order in the clockwise direction, and the coil bodies Cll to C18 that are adjacent in the circumferential direction are connected in series to each other, thereby configuring the first winding portion 71a.

[0071] In addition, the second winding portion 71b is configured by assembling two coil bodies 123 to each of the respective main pole portions 62 arranged in the circumferential direction, and connecting the coil bodies 123 in series. Here, the respective coil bodies 123 that are adjacent to the first winding portion 71a in the second winding portion 71b are C21, C22, C23,... C28 in that order, and the respective coil bodies 123 on the radially inner side are C31, C32, C33,... C38 in that order. The second winding portion 71b is configured by connecting one end of the series connection of the coil bodies C21 to C28 to one end of the series connection of the coil bodies C31 to C38. In Figure 11 In the present embodiment, the coil bodies 123 assembled to each of the main pole portions 62 are provided in two, but the same applies to a case where three or more are provided.

[0072] Figure 12 is a perspective view showing a structure related to connection of the coil bodies 121, 123 in each of the winding portions 71a, 71b in the rotor 60. Figure 12 shows a state where the circuit assembly 102 is assembled to one side in the axial direction of the rotor main portion 101.

[0073] The circuit assembly 102 has a component holder 130 that holds each of the capacitors 91, 92, and the diode 93 described above. The component holder 130 is configured of a material having electrical insulation, such as synthetic resin. The component holder 130 has a main portion 131 in the shape of a circular ring, and a plurality of lead fixing portions 132 that extend radially outward from the main portion 131 in a radial direction. In Figure 12 In the present embodiment, the main portion 131 is covered by the resin molding portion 105 and is not shown, but each of the capacitors 91, 92, and the diode 93 is arranged and disposed at a position in the main portion 131 that is in the shape of a circular ring that surrounds the rotation axis 32.

[0074] The component holder 130 is provided with the same number (eight) of lead fixing portions 132 as the main pole portion 62. A plurality of insertion holes 133 that pass through in the axial direction are formed in each lead fixing portion 132. The lead end portions 125, 126 that extend from the coil bodies 121, 123 of each winding portion 71a, 71b are inserted through these respective insertion holes 133, and the lead end portions 125, 126 that have been inserted through the lead end portions 125, 126 are joined to each other by welding or the like.

[0075] The three lead fixing portions 132A, 132B, 132C shown in FIG. 6 are described in detail. Figure 12

[0076] In the lead fixing portion 132A, for each coil body 121, 123 arranged in four columns in the radial direction, the coil bodies in the same column are connected to each other. Specifically, in the lead fixing portion 132A, the lead end portions 125 of each coil body 121 that are adjacent in the circumferential direction are inserted one by one into the insertion holes 133 in the connecting portion XI, and the lead end portions 125 are connected to each other. Also, the lead end portions 126 of each coil body 123 that are adjacent in the circumferential direction are inserted one by one into the insertion holes 133 in the connecting portions X2 to X4, and the lead end portions 126 are connected to each other. In the connecting portion X5, the bus bars 141, 142 for connection to the first capacitor 91 are connected.

[0077] In the connecting portions XI to X4, that is, the portions where the lead end portions 125 of each coil body 121, 123 or the lead end portions 126 of each coil body 121, 123 are connected to each other, each coil body 121, 123 is connected in a state in which the long sides of the lead wires that are flat wires are joined to each other by welding or the like. In this case, a large joining surface can be ensured compared to a structure in which the short sides of the lead wires are joined to each other. Therefore, appropriate connection can be performed from either of the strength and the conductivity.

[0078] ​In the lead fixing portion 132A, the lead end portions 126 of the coil bodies 123 are connected to each other in three portions, connection portions X2 to X4. That is, in the second winding portion 71b, the lead end portions 126 are connected to each other in the same number of portions as the coil bodies 123 arranged in the circumferential direction. Here, as a structure in which the conductor cross-sectional area of the lead wire C2 of the coil body 123 is smaller than that of the lead wire C1 of the coil body 121, it is assumed that the width dimension in the radial direction of the lead wire C2 is smaller than that of the lead wire C1 in the second winding portion 71b, and the number of coil bodies 123 arranged in the radial direction increases, and the connection portions of the coil bodies 123 to each other increase. In this regard, in the present embodiment, as a structure for reducing the cross-sectional area of the lead wire C2, since the width dimension in the circumferential direction of the lead wire C2 is smaller than that of the lead wire C1, the number of coil bodies 123 arranged in the radial direction does not increase. Thus, reduction in workability due to an increase in the connection portions of the coil bodies 123 to each other can be suppressed.

[0079] On the other hand, in the lead fixing portion 132B, connection of the coil bodies of different columns to each other (path conversion connection), connection of each capacitor 91, 92, diode 93 via the bus bar in the coil bodies 121, 123 of each column is performed. Specifically, in the lead fixing portion 132B, in a connection portion Y1, the lead end portion 125 of the coil body 121 of the first winding portion 71a, one end portion of the bus bar 143 for the second capacitor 92, and an end portion of the bus bar 144 for connection of the cathode of the diode 93 are connected. The connection of this connection portion Y1 corresponds to the connection of the connection point Al in the circuit diagram of Figure 13 . In addition, in a connection portion Y2, the lead end portion 125 of the coil body 121 of the first winding portion 71a, the lead end portion 126 of the coil body 123 of the second winding portion 71b, and an end portion of the bus bar 142 for the first capacitor 91 are connected. The connection of this connection portion Y2 corresponds to the connection of the connection point A2 in the circuit diagram of Figure 13 .

[0080] In the connection portion Y2, the connection of the lead end portions 125, 126 of the coil bodies 121, 123 is performed in a state in which the lead wires C1, C2 having different conductor cross-sectional areas (see Figure 10 ) are joined. Specifically, the lead wires C1, C2 of the coil bodies 121, 123 are connected in a state in which the long sides thereof are joined to each other by welding or the like. In this case, although the conductor cross-sectional areas of the respective lead wires C1, C2 of the coil bodies 121, 123 are different, since the length dimension of the long side of the lead wire C2 of the coil body 123 is the same as that of the lead wire C1 of the coil body 121, the joining surfaces of the lead wires C2, C1 to each other can be sufficiently ensured.

[0081] The wire ends 126 of each coil body 123 in different columns are connected to each other in the connecting parts Y3 and Y4. In the connecting part Y5, busbars 143 and 145 for connecting to the second capacitor 92 are connected.

[0082] Furthermore, in the wire fixing part 132C, in the connecting part Z1, the wire end 126 of the coil body 123 of the second winding part 71b, the end of the busbar 146 shared by each capacitor 91, 92, and the end of the busbar 147 for anode connection of the diode 93 are connected. The connection of this connecting part Z1 is... Figure 13 In the circuit diagram, this is equivalent to the connection point A3.

[0083] The conductors C1 and C2 of at least one of the first winding section 71a and the second winding section 71b can be bundles (dividing lines) formed by combining multiple strands of wire.

[0084] Specifically, such as Figure 14 As shown in (a), the conductor C1 is composed of multiple strands 151 and an outer peripheral covering portion 152 covering each of these strands 151 from the outer peripheral side. Additionally, as... Figure 14 As shown in (b), conductor C2 is also composed of multiple strands 151 and an outer peripheral covering 152 that covers each of these strands 151 from the outer periphery. Conductors C1 and C2 are both constructed using the same strands 151, but their cross-sections differ due to the different number of strands 151. The strands 151 can be covered conductors having a conductor and an insulating film covering that conductor. Alternatively, conductors C1 and C2 can be configured to use different strands 151; for example, the cross-sectional area of ​​the strands 151 in conductor C1 can be larger than that in conductor C2. The strands 151 can be rectangular in shape, but they can also be round. Conductors C1 and C2 can also be stranded wires in which multiple strands 151 are twisted together.

[0085] In the rotating electric motor 40, since a high-frequency current corresponding to the excitation frequency flows through the excitation winding 70 of the rotor 60, the skin effect occurs in each winding section 71a and 71b. To address this, by setting the conductors C1 and C2 of each winding section 71a and 71b to be bundled wires formed by combining multiple strands 151, i.e., dividing the conductor cross-section into multiple dividing lines, the influence of the skin effect in each winding section 71a and 71b can be reduced.

[0086] In addition, in the field winding 70, the first winding portion 71a on the radially outer side is located on the side close to the stator 50, and the second winding portion 71b on the radially inner side is located on the side away from the stator 50. In the first winding portion 71a, there is a concern that eddy current loss is generated due to the link of leakage magnetic flux from the stator 50. As a countermeasure, the volume resistivity of the conductor material of the first winding portion 71a can be made larger than the volume resistivity of the conductor material of the second winding portion 71b.

[0087] Specifically, for example, the conductor material of the first winding portion 71a (coil body 121) is made of aluminum, and the conductor material of the second winding portion 71b (coil body 123) is made of copper. Alternatively, the conductor material of the first winding portion 71a can be made of CNT (carbon nanotube), and the conductor material of the second winding portion 71b can be made of copper. Thus, in the first winding portion 71a, the influence of leakage magnetic flux can be reduced, and the eddy current loss can be reduced. In addition, since the wire materials of the respective winding portions 71a, 71b are different from each other, for the second winding portion 71b, which is less affected by leakage magnetic flux, a material with a small resistance is used, and thus the reduction of current in the second winding portion 71b is suppressed.

[0088] In the case where the first winding portion 71a is made of aluminum wire and the second winding portion 71b is made of copper wire, the volume resistivity of the conductor material of the first winding portion 71a is larger and the specific gravity is smaller than the volume resistivity of the conductor material of the second winding portion 71b. Thus, in the first winding portion 71a on the radially outer side (the stator 50 side), in addition to the reduction of eddy current loss caused by leakage magnetic flux from the stator 50, the centrifugal force at the time of rotation of the rotor can also be reduced.

[0089] In the case where the first winding portion 71a and the second winding portion 71b are made of different materials, there is a concern that galvanic corrosion occurs due to the attachment of moisture to the joint portions thereof. In view of this, the joint portions of the wire materials in the first winding portion 71a and the second winding portion 71b can be covered with an insulating material.

[0090] Figure 15 is a longitudinal sectional view showing the state in which the wire end portion 125 of the coil body 121 is joined to the wire end portion 126 of the coil body 123 in the component holder 130 of the circuit assembly 102. In Figure 15In this case, the wire end portions 125, 126 of the coil bodies 121, 123 are inserted into the insertion holes 133 in the wire fixing portions 132 of the component holder 130 and are joined by welding or the like at the top end side. Then, a resin covering portion 161 made of a resin material such as epoxy resin is formed so as to cover the joined portions of the wire end portions 125, 126. The resin covering portion 161 can cover the entirety of the joined portions of the wire end portions 125, 126, and a portion thereof can be provided so as to enter the insertion holes 133 of the wire fixing portions 132. By the resin covering portion 161, even if the first winding portion 71a and the second winding portion 71b are made of different materials, the galvanic corrosion of the joined portions thereof can be suppressed.

[0091] Further, the resin covering portion 161 is not provided only at the joined portions of the wire end portion 125 of the coil body 121 and the wire end portion 126 of the coil body 123, but can be provided at other joined portions, i.e., the joined portions of the wire end portions 125 of the coil body 121 to each other and the joined portions of the wire end portions 126 of the coil body 123 to each other.

[0092] According to the above-described embodiment, the following excellent effects can be obtained.

[0093] In the field winding 70, the conductor cross-sectional area of the wire material C2 for the second winding portion 71b is smaller than the conductor cross-sectional area of the wire material C1 for the first winding portion 71a. Thereby, compared to a case in which the same conductor cross-sectional area wire material is used in the first winding portion 71a and the second winding portion 71b, the number of turns in the second winding portion 71b can be increased. As a result, an increase in the field current flowing through the field winding 70 can be achieved, and further, an increase in the torque of the rotary electric machine 40 can be achieved.

[0094] In the rotary electric machine 40, since a high-frequency current corresponding to the field frequency flows through the field winding 70 of the rotor 60, the influence of the skin effect is received in each winding portion 71a, 71b. In this regard, by using a bundle wire as the wire material of each winding portion 71a, 71b, the influence of the skin effect in each winding portion 71a, 71b can be reduced.

[0095] As the structure in which the conductor cross-sectional area of the wire material C2 of the second winding portion 71b is made smaller than the conductor cross-sectional area of the wire material C1 of the first winding portion 71a, in the wire material C2 of the second winding portion 71b, the length dimension of the long side is made the same as that of the wire material C1 of the first winding portion 71a, and the length dimension of the short side is made smaller than that of the wire material C1. Thereby, in the structure in which the long sides of each winding portion 71a, 71b are joined to each other, the joining surfaces of each other can be sufficiently ensured, and welding or the like can be appropriately performed.

[0096] In the second winding portion 71b, as the number of coil bodies 123 arranged in the radial direction increases, the number of connection sites at which the coil bodies 123 are connected to each other increases. In this regard, as described above, as a structure in which the conductor cross-sectional area of the conductor wire C2 of the second winding portion 71b is smaller than the conductor cross-sectional area of the conductor wire C1 of the first winding portion 71a, in the conductor wire C2 of the second winding portion 71b, the width dimension in the radial direction is made the same as that of the conductor wire C1 of the first winding portion 71a, and the width dimension in the circumferential direction is made smaller than that of the conductor wire C1. Thus, it is possible to suppress the adverse situation in which the number of connection sites at which the coil bodies 123 are connected to each other increases due to the increase in the number of coil bodies 123 arranged in the radial direction, and it is possible to increase the number of turns in the second winding portion 71b.

[0097] (Other Embodiments)

[0098] The above-described embodiments can be changed, for example, as follows.

[0099] The conductor wires C1, C2 of the respective winding portions 71a, 71b can also be a structure in which only one of them is a bundle, or a structure in which neither of the conductor wires C1, C2 is a bundle.

[0100] Figure 16 A structure in which the conductor wire C1 of the first winding portion 71a is a bundle and the conductor wire C2 of the second winding portion 71b is not a bundle but a single wire is indicated. In this case, in the first winding portion 71a in which leakage magnetic flux from the high-frequency excitation magnetic flux of the stator 50 is easily accepted, it is possible to improve the effect of reducing eddy current loss. On the other hand, a bundle is more likely to have a deviation in the outer diameter dimension than a single wire, and if the second winding portion 71b wound around the portion of the main pole portion 62 that is the radially inner side is a bundle, there is a concern that winding of the conductor wire will be obstructed due to the deviation in the dimension in the relatively narrow space. In this regard, by not making the second winding portion 71b a bundle but a single wire, it is possible to suppress obstruction of winding of the conductor wire.

[0101] In the above-described embodiments, as a structure in which the conductor cross-sectional area of the conductor wire C2 of the second winding portion 71b is smaller than the conductor cross-sectional area of the conductor wire C1 of the first winding portion 71a, in the conductor wire C2, the length dimension of the long side is made the same as that of the conductor wire C1 and the length dimension of the short side is made smaller (see Figure 10 ), but this can be changed. For example, the conductor wire C2 can also be a structure in which the length dimension of the short side is the same as that of the conductor wire C1 and the length dimension of the long side is smaller. Or, the conductor wire C2 can also be a structure in which the length dimensions of the long side and the short side are smaller than those of the conductor wire C1.

[0102] In the above-described embodiment, the wire material of each winding portion 71a, 71b is provided as a flat wire, but this can be changed. For example, the wire material of one of the winding portions 71a, 71b can be provided as a flat wire, and the wire material of the other can be provided as a round wire. Alternatively, both of the wire materials can be round wires.

[0103] In the above-described embodiment, the wire end portions of the coil bodies 121, 123 are joined to each other by welding in each winding portion 71a, 71b, but this can be changed, and the wire end portions can be joined to each other by riveting, bolt fastening, or the like.

[0104] The conductor materials of the winding portions 71a, 71b can be the same. Specifically, the conductor materials of the winding portions 71a, 71b can be, for example, any one of aluminum, copper, and CNT.

[0105] The rotary electric machine is not limited to the rotary electric machine of the inner rotor type, and can be a rotary electric machine of the outer rotor type. In the rotary electric machine of the outer rotor type, the stator 50 is disposed on the radially inner side, and the rotor 60 is disposed on the radially outer side. In this case, the main pole portion 62 protrudes from the annular yoke portion of the rotor core toward the radially inner side. In the field winding 70, the first winding portion 71a can be disposed on the radially inner side (the stator 50 side), and the second winding portion 71b can be disposed on the radially outer side (the opposite side of the stator).

[0106] In the stator 50, the stator core can be a toothless core in which no teeth are provided.

[0107] As the rotary electric machine, it is not limited to the rotary electric machine used as a vehicle-mounted main machine, and can be, for example, a rotary electric machine used as an ISG (Integrated Starter Generator) used as a motor / generator.

[0108] As the mobile body on which the rotary electric machine system is mounted, it is not limited to a vehicle, and can be, for example, an airplane or a ship. In addition, the rotary electric machine system is not limited to a system mounted on a mobile body, and can be a stationary system.

[0109] Although the present disclosure is described in accordance with the embodiment, it should be understood that the present disclosure is not limited to the embodiment, the structure. The present disclosure also includes various modifications, modifications within the scope of equivalents. Furthermore, various combinations or modes, and other combinations or modes including only one element, one or more elements, or less fall within the scope or the range of ideas of the present disclosure.

Claims

1. A winding-excited type rotary motor (40), comprising: Stator (50), the stator having stator windings (52); and The rotor (60) has a rotor core (61) and an excitation winding (70). The rotor core has a main pole portion (62) arranged in a circumferential direction and projecting radially, and the excitation winding is wound around the main pole portion. A high-frequency current for inducing an excitation current in the excitation winding flows through the stator winding, characterized in that... The excitation winding has a series connection of a first winding portion (71a) and a second winding portion (71b), with the first winding portion located radially closer to the stator and the second winding portion located radially away from the stator. These winding portions are wound around the respective main pole portions. The first winding portion forms a series resonant circuit by being connected in series with the capacitor (91), and the second winding portion forms a parallel resonant circuit by being connected in parallel with the capacitor. The second winding has more turns than the first winding, and the conductor cross-sectional area of ​​the wire used in the second winding is smaller than that of the wire used in the first winding.

2. The winding-excited rotary motor according to claim 1, characterized in that, The conductor of at least one of the first winding section and the second winding section is a bundle of multiple strands of wire.

3. The winding-excited rotary motor according to claim 1, characterized in that, This winding-excited rotary motor has an inner rotor structure with the stator positioned radially outward and the rotor positioned radially inward. The conductor of the first winding is a bundle of multiple strands of wire, while the conductor of the second winding is not the bundle of wire.

4. The winding-excited rotating electric motor according to any one of claims 1 to 3, characterized in that, The conductors of the first winding section and the second winding section are rectangular flat-angled conductors with long and short sides. The winding sections are connected in series by joining the long sides of these conductors together. Compared with the conductor of the first winding, the conductor of the second winding has the same length on its long side and a smaller length on its short side.

5. The winding-excited rotating electric motor according to any one of claims 1 to 3, characterized in that, The first winding section and the second winding section have coil bodies (121, 123) formed by winding wire in each of the main pole sections. The first winding section and the second winding section are formed by connecting the coil bodies of each main pole section in series. In the second winding section, the coil bodies are arranged in multiple rows radially in the main pole section, and the coil bodies in each row are connected to each other. Compared to the conductor of the first winding section, the conductor of the second winding section has the same radial width but a smaller circumferential width.

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