JP2017135853A - Rotary electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress torque decrease in a rotary electric machine that utilizes an axial surface as a torque surface.SOLUTION: The present invention relates to a rotary electric machine in which a stator and a rotor are disposed oppositely and an axial surface is used as a torque surface. A stator 120 comprises: an annular yoke part 210; multiple teeth 220 that are disposed in a circumferential direction of the annular yoke part 210 and protrude towards the axial surface of the rotor in a rotation axis direction; and a slot 230 which is disposed between the adjacent teeth and to which a stator coil 240 is mounted. An inner diameter side cross-sectional area and an outer diameter side cross-sectional area of an electrification surface of the slot 230 are made equal, an inner diameter side shape and an outer diameter side shape of the electrification surface of the slot 230 are made different, and an axial length at an outer diameter side is made shorter than that at an inner diameter side.SELECTED DRAWING: Figure 2A

Description

  The present invention relates to a rotating electrical machine, and more particularly to a stator structure.

  Conventionally, rotating electric machines such as an axial motor or an axial gap type motor using an axial surface as a torque generating surface have been proposed.

  Patent Document 1 describes an axial gap type motor including a rotor that can rotate around a rotation axis and a stator that is disposed to face the rotor from at least one side in the rotation axis direction. The stator includes an annular back yoke and a plurality of teeth projecting toward the rotor in the rotation axis direction at positions at predetermined intervals in the circumferential direction of the back yoke, and the teeth have a substantially fan-shaped rotor facing surface. As the circumferential width of the teeth facing the rotor decreases from one side to the other in the radial direction, the thickness of the back yoke in the rotational axis direction changes from one side to the other in the radial direction. Has been.

  FIG. 15 is an exploded perspective view of the axial gap type motor described in Patent Document 1. FIG. The axial gap type motor 100 is opposed to a substantially annular rotor 110 that is rotatably provided around the rotation axis O so as to sandwich the rotor 110 from both sides in the direction of the rotation axis O via a predetermined gap. A pair of stators 120 each having a plurality of phase stator windings that generate a rotating magnetic field for rotating the rotor 110 are provided.

  The stator 120 protrudes toward the rotor 110 in the direction of the rotation axis O from a position at a predetermined interval in the circumferential direction on the substantially annular plate-shaped yoke portion 210 and a facing surface of the yoke portion 210 facing the rotor 110. A plurality of teeth 220 extending in the radial direction and a stator winding mounted in a slot 230 between adjacent teeth 220 in the circumferential direction are provided. The stator 120 is fixed to the housing using a plurality of bolt holes provided on the end surface of the yoke part 210.

  FIG. 16 is a top view of the stator 120. The width a on the inner diameter side and the width b on the outer diameter side of the slot 230 between the teeth 220 are the same (a = b).

JP 2009-95086 A

  In the prior art, focusing on the fact that the amount of magnetic flux increases toward the outer diameter side, the cross-sectional area of the back yoke is increased on the outer diameter side, but the width a on the inner diameter side of the slot between the teeth and the outer diameter side The width b is the same, and the cross-sectional area is the same on the inner diameter side and the outer diameter side. Since the tooth shape is determined according to such a slot shape, the shape of the magnet on the rotor side does not coincide with the substantially fan shape, and the magnetic flux density is uneven in the radial direction, causing local magnetic saturation. There is a problem that the torque is easily reduced.

  On the other hand, as shown in FIG. 17, the side surface of the tooth 220 is formed along a line extending radially from the center O ′ of the rotation axis O while making the width a on the inner diameter side of the slot the same as the width b on the outer diameter side. Therefore, it is conceivable that the rotor-facing surface of the teeth 220 has a substantially sector shape. In this case, however, the width of the outer diameter side of the teeth 220 is shorter than that in the case of FIG. As a result, the cross-sectional area decreases and the magnetic resistance increases.

  The present inventors have confirmed by a computer magnetic analysis that the torque is reduced by 3.9% in the shape of the tooth 220 shown in FIG. 17, that is, a so-called radial tooth, as compared with the case of FIG.

  The present invention has been made in view of the problems of the related art, and an object of the present invention is to suppress torque reduction in a rotating electrical machine that uses an axial surface as a torque surface.

  A rotating electrical machine according to the present invention is a rotating electrical machine in which a stator and a rotor are opposed to each other, and an axial surface is used as a torque surface. The stator is disposed in the circumferential direction of the annular yoke portion and the annular yoke portion, and the rotating shaft A plurality of teeth projecting in the direction toward the axial surface of the rotor and a slot disposed between adjacent teeth and fitted with a stator winding, and an inner diameter side cross-sectional area and an outer diameter of a current-carrying surface of the slot The side cross-sectional areas are the same, and the inner diameter side shape and the outer diameter side shape of the current-carrying surface of the slot are different.

  In one embodiment of the present invention, the inner diameter side shape and the outer diameter side shape of the current-carrying surface of the slot are both rectangular and have different aspect ratios.

In another embodiment of the present invention, the outer diameter side width of the current-carrying surface of the slot is longer than the width on the inner diameter side, and the axial length of the outer-diameter side of the current-carrying surface of the slot is shorter than the axial length of the inner diameter side.
In yet another embodiment of the present invention, the axial length of the annular yoke portion on the outer diameter side is longer than the axial length on the inner diameter side.

  In still another embodiment of the present invention, the teeth have a substantially fan-shaped rotor facing surface.

  According to the present invention, the inner diameter side shape and the outer diameter side shape of the current-carrying surface of the slot are made different, and the magnetic path length of the magnet magnetic flux on the outer diameter side is adjusted to reduce the magnetic resistance and the leakage magnetic flux, thereby reducing the torque. Can be suppressed. In addition, according to the present invention, the inner diameter side shape and the outer diameter side shape of the current-carrying surface of the slot are made different, and the shape of the teeth facing the rotor is made substantially fan-shaped, so that the magnetic flux density in the radial direction is made uniform. Thus, torque reduction can be further suppressed.

It is a top view of the stator of the first embodiment. It is a perspective view of the stator of 1st Embodiment. It is a typical perspective view of the stator winding | coil (slot) of 1st Embodiment. It is a perspective view of the yoke part of 1st Embodiment. It is a graph which shows the magnetic analysis result of 1st Embodiment. It is a perspective view of the yoke part of 2nd Embodiment. It is a graph which shows the magnetic analysis result of 2nd Embodiment. It is a perspective view of the yoke part of 3rd Embodiment. It is FIG. (1) which shows the basic schematic structure of the rotary electric machine of 4th Embodiment. It is FIG. (2) which shows the basic schematic structure of the rotary electric machine of 4th Embodiment. It is FIG. (3) which shows the basic schematic structure of the rotary electric machine of 4th Embodiment. It is FIG. (The 4) which shows the basic schematic structure of the rotary electric machine of 4th Embodiment. It is FIG. (The 5) which shows the basic schematic structure of the rotary electric machine of 4th Embodiment. It is FIG. (6) which shows the basic schematic structure of the rotary electric machine of 4th Embodiment. It is a perspective view of the yoke part of 4th Embodiment. It is a disassembled perspective view of an axial gap type motor. It is a stator top view of the motor shown in FIG. FIG. 16 is a top view of another stator of the motor shown in FIG. 15.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
<First Embodiment>
The overall configuration of the axial gap type rotating electrical machine of this embodiment is substantially the same as the overall configuration of the axial gap type motor shown in FIG.

  That is, the substantially annular rotor 110 provided to be rotatable around the rotation axis O is disposed opposite to the rotor 110 so as to sandwich the rotor 110 from both sides in the direction of the rotation axis O via a predetermined gap, and the rotor 110 is rotated. A pair of stators 120 each having a plurality of stator windings that generate a rotating magnetic field are provided.

  The stator 120 protrudes toward the rotor 110 in the direction of the rotation axis O from a position at a predetermined interval in the circumferential direction on the substantially annular plate-shaped yoke portion 210 and a facing surface of the yoke portion 210 facing the rotor 110. A plurality of teeth 220 extending in the radial direction and a stator winding mounted in a slot 230 between adjacent teeth 220 in the circumferential direction are provided. The stator 120 is fixed to the housing using a plurality of bolt holes provided on the end surface of the yoke part 210.

  However, the stator 120 in this embodiment is different from the stator 120 shown in FIG. 15 in the shape of the teeth 220 and the shape of the slots 230.

  FIG. 1 is a top view of the stator 120 in the present embodiment. The width a on the inner diameter side and the width b on the outer diameter side of the slots 230 between the teeth 220 are not the same, and the width b on the outer diameter side is larger than the width a on the inner diameter side, and a <b. Further, by forming the side surface of the tooth 220 along a line extending radially from the center O ′ of the rotation axis O, the shape of the rotor-facing surface of the tooth 220 is substantially fan-shaped. This is the same as the radial teeth shown in FIG.

  Further, the length (axial length) of the slot 230 in the rotation axis O direction (perpendicular to the paper surface in FIG. 1) is not the same on the inner diameter side and the outer diameter side, and is longer on the outer diameter side than the inner diameter side. Reduce the thickness.

  In other words, in this embodiment, the cross-sectional area of the energizing surface of the slot 230 in which the stator winding is mounted is the same on the inner diameter side and the outer diameter side, and the width b on the outer diameter side is larger than the width a on the inner diameter side. And the axial length on the outer diameter side is made smaller than the axial length on the inner diameter side.

  FIG. 2A shows a perspective view of the stator 120 of the present embodiment. The stator winding 240 is wound around the teeth 220. 2B is an enlarged view in which only the stator winding 240 mounted in the slot 230 in FIG. 2A is taken out.

2A and 2B, the axial length on the inner diameter side of the slot 230 in the direction of the rotation axis O is indicated by c, and the axial length on the outer diameter side is indicated by d. In the conventional stator 120 shown in FIG. 16, c = d, but in this embodiment, c> d. In other words, in order to make the cross-sectional area S1 of the current-carrying surface on the inner-diameter side of the stator winding 240 mounted in the slot 230 the same as the cross-sectional area S2 of the current-carrying surface on the outer-diameter side, Width b of a <b
And the axial length c on the inner diameter side and the axial length d on the outer diameter side are c> d
As
S1 = a · c = b · d = S2
It is what.

The cross-sectional area of the energizing surface of the slot 230 is a rectangular shape on both the inner diameter side and the outer diameter side as shown in FIG. 2B.
a <b
c> d
Is different from each other in the shape of the current-carrying surface on the inner diameter side and the current-carrying surface on the outer diameter side, and more specifically, the aspect ratio of the rectangular current-carrying surface on the inner diameter side and the rectangular current-carrying surface on the outer diameter side Are different from each other in aspect ratio. On the other hand, in the stator 120 of FIG. 16 or FIG. 17, the aspect ratio of the rectangular energizing surface on the inner diameter side and the aspect ratio of the rectangular energizing surface on the outer diameter side are the same.

Since the axial length of the slot 230 is the axial length of the tooth 220, the axial length c on the inner diameter side and the axial length d on the outer diameter side of the slot 230 are set as c> d
Is that the axial length c on the inner diameter side and the axial length d on the outer diameter side of the tooth 220 are c> d
Is equivalent to

  Thus, according to the stator 120 of the present embodiment, the axial length d on the outer diameter side of the tooth 220 is shorter than the inner diameter side, that is, shorter than the conventional tooth 220 shown in FIG. The magnetic path length of the magnet magnetic flux is shortened, and the magnetic resistance is reduced. Further, since the axial length d on the outer diameter side of the tooth 220 is shortened, leakage magnetic flux that does not reach the yoke part 210 and is short-circuited between adjacent teeth 220 can be reduced. Furthermore, since the shape of the rotor facing surface of the teeth 220 is substantially fan-shaped, the magnetic flux density is made uniform in the radial direction to prevent local magnetic saturation, and as a result, torque reduction can be suppressed.

  Although the axial length d on the outer diameter side of the tooth 220 is shorter than the inner diameter side, the yoke portion 210 may be kept the same on the inner diameter side and the outer diameter side as in the prior art. This is because the magnetic flux passage cross-sectional area of the conventional shape and the yoke portion 210 may be the same on the magnetic circuit (uniform magnetic flux density). FIG. 3 shows a perspective view of the yoke part 210 in this case. As the axial length d on the outer diameter side of the tooth 220 is shortened, the outer diameter portion of the yoke portion 210 is brought closer to the gap surface.

  FIG. 4 shows the result of magnetic analysis by a computer, and shows the torque of the rotating electrical machine in this embodiment (Embodiment 1) and the torque of the conventional rotating electrical machine shown in FIG. In this embodiment, the torque is increased by 2.3% compared to the conventional case.

Second Embodiment
FIG. 5 is a perspective view of the stator 120 in the present embodiment.

  In the stator 120 shown in FIG. 3, the axial length on the inner diameter side and the axial length on the outer diameter side of the yoke portion 210 are the same, but in this embodiment, the axial length e on the inner diameter side of the yoke portion 210 and the outer diameter side shaft. The length f has a relationship of e <f.

That is, also in the present embodiment, the shape of the rotor facing surface of the tooth 220 is substantially fan-shaped as in the first embodiment, and the axial length c on the inner diameter side of the slot 230 or the tooth 220 and the axial length d on the outer diameter side are c> d
However, the shaft length f on the outer diameter side of the yoke portion 210 is made longer than that on the inner diameter side by the amount that the shaft length d on the outer diameter side of the tooth 210 is made shorter than that on the inner diameter side.

  In this way, by increasing the axial length f on the outer diameter side of the yoke part 210, the magnetic flux passage cross-sectional area of the yoke part 210 is increased, so that the magnetic resistance is reduced and the torque is further increased than in the first embodiment. Will increase.

  FIG. 6 shows the magnetic analysis results by the computer, and shows the torque of the rotating electrical machine in the present embodiment (Embodiment 2) and the torque of the conventional rotating electrical machine shown in FIG. In this embodiment, the torque is increased by 4.4% compared to the conventional case.

<Third Embodiment>
In 2nd Embodiment, although the shape of the rotor opposing surface of the teeth 220 is made into the substantially fan shape, it is good also as another shape.

  FIG. 7 is a perspective view of the stator 120 in the present embodiment. The shape of the tooth-facing surface of the tooth 220 is a straight shape instead of a substantially fan shape. Also in this case, as in the first embodiment, since the axial length of the tooth 220 on the outer diameter side is shorter than the conventional one, the magnetic path length of the magnet magnetic flux is shortened, and the magnetic resistance is reduced. Further, since the axial length of the tooth 220 on the outer diameter side is shortened, leakage magnetic flux that does not reach the yoke portion 210 and is short-circuited between adjacent teeth 220 can be reduced. Further, similarly to the second embodiment, the magnetic flux passage cross-sectional area of the yoke portion 210 increases, so that the magnetic resistance decreases and the torque increases.

<Fourth embodiment>
In the first to third embodiments, an example is shown in which an axial gap type rotating electrical machine that uses an axial surface as a torque surface is shown. However, the present invention can also be applied to a rotating electrical machine that uses an axial surface and a radial surface as a torque surface. it can. In this embodiment, this case will be described.

  8-12 is a figure which shows schematic structure of the rotary electric machine 10. As shown in FIG. 8 and 9 are cross-sectional views showing an outline of the internal configuration of the rotor and the stator as viewed from the direction orthogonal to the rotation shaft 22, FIG. 10 is a perspective view showing the configuration of the rotor, and FIGS. It is a perspective view which shows the structure of a stator. 8 shows a cross-sectional view at a position corresponding to the AA cross section of FIG. 10, and FIG. 9 shows a cross-sectional view at a position corresponding to the BB cross section of FIG.

  The rotating electrical machine 10 includes a stator 12 fixed to the casing 11 and a rotor that is disposed to face the stator 12 and is rotatable with respect to the stator 12. The rotor includes a radial rotor 14 disposed opposite to the stator 12 in a radial direction (hereinafter simply referred to as radial direction) orthogonal to the rotor rotation axis (rotation axis 22), and a direction parallel to the rotor rotation axis (rotation axis 22) (hereinafter referred to as “rotation axis 22”). The axial rotor 64 has two axial rotors 64 and 84 that are disposed opposite to the stator 12 and mechanically and magnetically coupled to the radial rotor 14. Both the radial rotor 14 and the axial rotors 64 and 84 are mechanically connected to the nonmagnetic rotating shaft 22, and the radial rotor 14, the axial rotors 64 and 84, and the rotating shaft 22 rotate as a unit. In the example shown in FIGS. 1 to 5, the radial rotor 14 is disposed on the radially inner side of the stator 12, and faces the inner peripheral surface (radial surface) of the stator 12 with a predetermined gap (air gap). Two axial rotors 64 and 84 are arranged on the outer side in the rotation axis direction of the stator 12 with the stator 12 interposed therebetween, and are opposed to both side surfaces (axial surfaces) of the stator 12 with a predetermined gap.

  The stator 12 includes an annular core portion 26 and a plurality of (for example, three-phase) armature windings 28 that are toroidally wound around the annular core portion 26. The stator 12 has a plurality of radial teeth 30 projecting radially from the inner peripheral surface of the annular core portion 26 toward the radial rotor 14 in the radial direction (inward in the radial direction). ) Are spaced apart from each other (at equal intervals), and slots are formed between the radial teeth 30. Further, the stator 12 has a plurality (same number as the radial teeth 30) of axial teeth 80 protruding in the circumferential direction from both side surfaces of the annular core portion 26 toward the axial rotor 64 in the rotation axis direction (rotation axis direction outer side). Are arranged at equal intervals (equal intervals), and slots are formed between the axial teeth 80. The radial teeth 30 and the axial teeth 80 are arranged so that their positions in the circumferential direction are not shifted from each other, and the slots between the radial teeth 30 and the slots between the axial teeth 80 are also arranged so that their positions in the circumferential direction are not shifted from each other. The three-phase armature windings 28 are toroidally wound through slots between the radial teeth 30 and slots between the axial teeth 80 (for example, with distributed winding). The annular core portion 26, the radial teeth 30 and the axial teeth 80, that is, the iron core portion of the stator 12, for example, was coated with a film that does not conduct electricity on the surface of ferromagnetic fine particles such as iron. It can be formed of a three-dimensional isotropic magnetic material such as a dust core material obtained by compacting powder.

  The radial rotor 14 includes a substantially cylindrical radial core 16 and a plurality of radial permanent magnets 18 disposed on the outer peripheral portion of the radial core 16 so as to face the stator 12 (radial teeth 30) in the radial direction. A plurality of radial salient pole portions 19 (the same number as the radial permanent magnets 18) projecting radially outward toward the stator 12 (radial teeth 30) are spaced apart from each other along the circumferential direction on the outer peripheral portion of the radial core 16. And are arranged at regular intervals. Each radial salient pole portion 19 faces the stator 12 (radial teeth 30) in the radial direction. The plurality of radial permanent magnets 18 are arranged at regular intervals (equal intervals) along the circumferential direction, and are arranged at positions between the radial salient pole portions 19 in the circumferential direction. That is, each radial permanent magnet 18 is arranged with a position in the circumferential direction shifted from the radial salient pole portion 19, and the radial permanent magnet 18 and the radial salient pole portion 19 are alternately arranged in the circumferential direction. The radial permanent magnets 18 are magnetized in the same direction, and the surface of each radial permanent magnet 18 (the magnetic pole surface facing the stator 12) is magnetized to the same polarity (for example, N pole).

  The axial rotor 64 includes a substantially annular axial core 66 and a plurality of axial permanent magnets 68 disposed on the side surface of the axial core 66 so as to face the stator 12 (axial teeth 80) in the rotation axis direction. The axial core 66 is mechanically and magnetically coupled to the radial core 16. A plurality of (same number as the axial permanent magnets 68) axial salient pole portions 69 projecting in the rotation axis direction (inward in the rotation axis direction) toward the stator 12 (axial teeth 80) are provided on the side surface of the axial core 66 along the circumferential direction. Are arranged at regular intervals (equal intervals). Each axial salient pole portion 69 faces the stator 12 (axial teeth 80) in the rotation axis direction. The plurality of axial permanent magnets 68 are arranged at regular intervals (equal intervals) along the circumferential direction, and are arranged at positions between the axial salient pole portions 69 in the circumferential direction. That is, as shown in FIG. 13, each axial permanent magnet 68 is arranged with a position in the circumferential direction shifted from the axial salient pole portion 69, and the axial permanent magnet 68 and the axial salient pole portion 69 are arranged in the circumferential direction. Are lined up alternately. The magnetization directions of the axial permanent magnets 68 are the same, and the surfaces of the axial permanent magnets 68 (the magnetic pole surfaces facing the stator 12) are magnetized to the same polarity (for example, S pole).

  Similarly, the axial rotor 84 includes a substantially annular axial core 86 and a plurality of axial permanent magnets 88 disposed on the side surface of the axial core 86 so as to face the stator 12 (axial teeth 80) in the rotation axis direction. Including. The axial core 86 is mechanically and magnetically coupled to the radial core 16. A plurality of (same number as the axial permanent magnets 88) axial salient pole portions 89 projecting in the rotational axis direction (inward in the rotational axis direction) toward the stator 12 (axial teeth 80) are provided on the side surface of the axial core 86 along the circumferential direction. Are arranged at regular intervals (equal intervals). Each axial salient pole portion 89 faces the stator 12 (axial teeth 80) in the rotation axis direction. The plurality of axial permanent magnets 88 are arranged at regular intervals (equal intervals) along the circumferential direction, and are arranged at positions between the axial salient pole portions 89 in the circumferential direction.

  The number of the axial permanent magnets 88 is the same as the number of the axial permanent magnets 68, and the number of the axial salient pole portions 89 is the same as the number of the axial salient pole portions 69. The axial permanent magnet 88 is disposed without shifting the position in the circumferential direction with respect to the axial permanent magnet 68, and faces the axial permanent magnet 68 with the stator 12 interposed therebetween in the rotation axis direction. The axial salient pole part 89 is also arranged without shifting the position in the circumferential direction with respect to the axial salient pole part 69, and faces the axial salient pole part 69 with the stator 12 interposed in the rotation axis direction. The surface of each axial permanent magnet 88 (the magnetic pole surface facing the stator 12) is magnetized to the same polarity (for example, S pole) as the surface of each axial permanent magnet 68 (the magnetic pole surface facing the stator 12).

  Further, the radial permanent magnets 18 are provided in the same number as the axial permanent magnets 68 (axial permanent magnets 88), and the radial salient pole portions 19 are provided in the same number as the axial salient pole portions 69 (axial salient pole portions 89). The axial permanent magnets 68 and 88 are arranged with their positions in the circumferential direction shifted from the radial permanent magnet 18, and the axial salient pole parts 69 and 89 are also arranged with their positions in the circumferential direction shifted from the radial salient pole part 19. Has been. And the axial permanent magnets 68 and 88 and the radial salient pole part 19 are arrange | positioned without the position regarding a circumferential direction shifting | deviating mutually, and the position about the axial salient pole parts 69 and 89 and the radial permanent magnet 18 also shift | deviated mutually. It is arranged without. Further, the surfaces of the axial permanent magnets 68 and 88 (the magnetic pole surfaces facing the stator 12) are magnetized to have opposite polarities to the surfaces of the radial permanent magnets 18 (the magnetic pole surfaces facing the stator 12). In the example shown in FIGS. 10 and 13, the surface of each radial permanent magnet 18 is magnetized to the N pole, and the surface of each axial permanent magnet 68, 88 is magnetized to the S pole. However, the surface of each radial permanent magnet 18 may be magnetized to the S pole, and the surface of each axial permanent magnet 68, 88 may be magnetized to the N pole.

  By flowing a plurality of phases (three phases) of alternating current through the plurality of phases (three phases) of the armature winding 28, the radial teeth 30 and the axial teeth 80 are sequentially magnetized, and a rotating magnetic field rotating in the circumferential direction is applied to the stator 12. It is formed. The rotating magnetic field generated in the stator 12 acts on the radial rotor 14 and the axial rotors 64 and 84 from the radial teeth 30 and the axial teeth 80, respectively, and the magnetic fields (field magnetic fluxes) generated by the radial permanent magnet 18 and the axial permanent magnets 68 and 88. ) Interacts with this rotating magnetic field, causing attraction and repulsion. Due to the electromagnetic interaction (attraction and repulsion) between the rotating magnetic field of the radial teeth 30 and the axial teeth 80 and the field magnetic flux of the radial permanent magnets 18 and the axial permanent magnets 68 and 88, the radial rotor 14 and the axial rotors 64 and 84 Torque (magnet torque) can be applied.

  While the toroidal winding is easier to manufacture the winding than the distributed winding, the number of windings that do not work effectively for the generation of the torque of the rotor is likely to increase. In the basic configuration, not only the front end surface (radial surface) of the radial teeth 30 but also the front end surface (axial surface) of the axial teeth 80 is used as a torque generation surface for generating torque by applying a rotating magnetic field to the rotor. Thus, the torque generation area can be increased. As a result, it is possible to reduce the number of windings that do not work effectively to generate torque of the rotor (radial rotor 14 and axial rotors 64 and 84), and to increase the torque of the rotor while suppressing an increase in physique and copper loss. it can.

  In addition, field windings 70 and 90 are provided on the stator 12 in order to control the field magnetic flux that interacts with the rotating magnetic field of the stator 12. Each field winding 70, 90 is wound in an annular shape along the circumferential direction. The position where the field winding 70 passes (winds) is closer to the radial rotor 14 (the radial permanent magnet 18 and the radial salient pole portion 19) than the annular core portion 26 in the radial direction, and in the rotation axis direction. It is a position closer to the axial rotor 64 (the axial permanent magnet 68 and the axial salient pole part 69) than the annular core part 26. The position where the field winding 90 passes (winds) is closer to the radial rotor 14 (the radial permanent magnet 18 and the radial salient pole portion 19) than the annular core portion 26 in the radial direction, and the rotation axis. It is a position closer to the axial rotor 84 (axial permanent magnet 88 and axial salient pole part 89) than the annular core part 26 with respect to the direction. In the example shown in FIGS. 8 to 12, the field windings 70, 90 are on the radial rotor 14 side (inner side) with respect to the radial teeth 80 in the radial direction, and are axial rotors relative to the radial teeth 30 in the rotation axis direction. The radial teeth 30, the axial teeth 80, and the armature windings 28 are arranged close to the 64 and 84 (outside) positions. The field windings 70 and 90 are electrically insulated from the armature winding 28 by an insulator. Further, a convex curved surface 28 a is formed in a portion close to the field windings 70 and 90 on the outer peripheral surface of each armature winding 28. The outer diameter of the outer peripheral surface of the field winding 70 adjacent to the convex curved surface 28a of each armature winding 28 is gradually increased from the axial rotor 64 side to the annular core portion 26 side (from the outside to the inside) in the rotation axis direction. The outer diameter of the outer peripheral surface of the field winding 90 adjacent to the convex curved surface 28a of each armature winding 28 is gradually reduced from the axial rotor 84 side toward the annular core portion 26 side in the rotation axis direction. doing. Note that the field windings 70 and 90 may be fixed to the stator 12 by, for example, tying the armature windings 28 with fibers 71 or the like as shown in FIG. The whole may be fixed by molding with resin or the like.

In the example shown in FIGS. 10 and 13 (example in which the surface of the radial permanent magnet 18 is N pole and the surfaces of the axial permanent magnets 68 and 88 are S poles), the radial permanent magnet 18 and the axial permanent magnet 68, The field flux by 88 is
Radial permanent magnet 18 → air gap → radial tooth 30 → annular core portion 26 → axial tooth 80 → air gap → axial permanent magnets 68 and 88 → axial cores 66 and 86 → radial core 16 → radial permanent magnet 18
(When the surface of the radial permanent magnet 18 is magnetized to the S pole and the surfaces of the axial permanent magnets 68 and 88 are magnetized to the N pole, the direction of the field magnetic flux is reversed).

  Furthermore, by supplying a direct current (field current) to the field windings 70 and 90, the radial salient pole part 19, the radial core 16, the axial cores 66 and 86, the axial salient pole parts 69 and 89, the air gap, the axial A field magnetic flux passing through a closed magnetic path is generated by the teeth 80, the annular core portion 26, the radial teeth 30, the air gap, and the radial salient pole portion 19, and this field magnetic flux causes an alternating current to flow through the armature winding 28. It interacts with the rotating magnetic field generated in the stator 12. At that time, the surface of each radial salient pole portion 19 (surface facing the stator 12) is magnetized to the same polarity, and the surface of each axial salient pole portion 69, 89 (surface facing the stator 12) is the same polarity. Is magnetized. However, the surface of each of the axial salient pole portions 69 and 89 is magnetized to a polarity opposite to that of the surface of each radial salient pole portion 19. The direction of the field magnetic flux generated by the field windings 70 and 90 can be controlled by the direction of the direct current flowing through the field windings 70 and 90, and the radial salient pole portion 19 and the axial salient pole portions 69 and 89 can be selected. Whether it is magnetized to the polarity (N pole or S pole) can also be controlled by the direction of the direct current flowing through the field windings 70 and 90. The magnitude of the field magnetic flux generated by the field windings 70 and 90 can be controlled by the magnitude of the direct current flowing through the field windings 70 and 90.

  FIG. 14 is a perspective view of the axial teeth 80 and the yoke portion 210 of the rotor 12. FIG. 14A shows the basic configuration of the axial teeth 80 and the yoke portion 210. The axial teeth 80 are similar to the planar shape shown in FIG. The width on the outer diameter side is equal, and the axial length on the inner diameter side and the axial length on the outer diameter side of the axial teeth 80 are equal.

  On the other hand, FIG.14 (b) shows the perspective view of the axial teeth 80 and the yoke part 210 of the rotor 12 in this embodiment. 14A, the planar shape of the axial teeth 80 is substantially fan-shaped as in the first to third embodiments (radial axial teeth), and the axial length of the axial teeth 80 is set to the inner diameter side axis. The axial length on the outer diameter side of the yoke portion 210 is made longer than the axial length on the inner diameter side. That is, if the axial length on the inner diameter side of the axial teeth 80 in FIGS. 14 (a) and 14 (b) is c1, and the axial length on the inner diameter side of the yoke portion 210 is e1, in FIG. 14 (a), c1 = d1, e1 = F1, where c1> d2 and e1 <f2 in FIG. 14B.

  Also in the present embodiment, as in the first embodiment, since the axial length of the axial teeth 80 on the outer diameter side is shortened, the magnetic path length of the magnet magnetic flux is shortened, and the magnetic resistance is reduced. Further, since the axial length on the outer diameter side of the axial teeth 80 is shortened, leakage magnetic flux that does not reach the yoke portion 210 and is short-circuited between adjacent axial teeth 80 can be reduced. Moreover, since the shape of the axial teeth 80 is substantially fan-shaped, the magnetic flux density can be made uniform in the radial direction to prevent local magnetic saturation, and torque reduction can be suppressed. Further, similarly to the second embodiment, by increasing the axial length of the yoke portion 210 on the outer diameter side, the magnetic flux passing cross-sectional area of the yoke portion 210 is increased, thereby reducing the magnetic resistance and increasing the torque. When the torque of the rotating electrical machine in the present embodiment (Embodiment 4) is compared with the torque of the rotating electrical machine including the conventional stator 12 shown in FIG. It has been confirmed that the torque is increased by 2.0%.

  DESCRIPTION OF SYMBOLS 10 Rotating electrical machine, 11 Casing, 12 Stator, 14 Radial rotor, 18 Radial permanent magnet, 19, 39 Radial salient pole part, 22 Rotating shaft, 30 Radial teeth, 64, 84 Axial rotor, 68, 88 Axial permanent magnet, 69, 89 Axial salient poles, 80 Axial teeth, 120 Stator, 210 Yoke part, 220 teeth, 230 slots, 240 Stator windings.

Claims (5)

A rotating electrical machine in which a stator and a rotor are arranged to face each other, and an axial surface is used as a torque surface,
The stator is
An annular yoke portion;
A plurality of teeth disposed in the circumferential direction of the annular yoke portion and projecting toward the axial surface of the rotor in the rotation axis direction;
A slot disposed between adjacent teeth and fitted with a stator winding;
With
The inner diameter side sectional area and the outer diameter side sectional area of the current-carrying surface of the slot are the same,
The inner diameter side shape and outer diameter side shape of the current-carrying surface of the slot are different.
Rotating electric machine characterized by that. Both the inner diameter side shape and outer diameter side shape of the current-carrying surface of the slot are rectangular, and the aspect ratios are different from each other.
The rotating electrical machine according to claim 1. The outer diameter side width of the current carrying surface of the slot is longer than the inner diameter side width,
The axial length on the outer diameter side of the current-carrying surface of the slot is shorter than the axial length on the inner diameter side.
The rotating electrical machine according to claim 2. The axial length of the annular yoke portion on the outer diameter side is longer than the axial length on the inner diameter side,
The rotating electrical machine according to claim 3. The teeth have a substantially fan-shaped rotor facing surface,
The rotating electrical machine according to any one of claims 1 to 4.