Rotary electric machine and driving system

Abstract

To provide a rotary electric machine capable of preventing a stator winding from falling out of a slot and capable of obtaining a large torque.SOLUTION: A rotary electric machine according to the present invention includes a stator 2 having stator cores 4 and a stator winding 5, and a rotor 3 having a rotatable shaft 8 disposed opposite to the stator 2 with a gap therebetween and extending in an axial direction. The stator core 4 includes a plurality of stator slots 12 extending in the axial direction and accommodating the stator winding 5, and a wedge 20 disposed at an opening of the stator slot 12 and supporting the stator winding 5. The stator slot 12 includes a groove 14 extending in the axial direction on both side surfaces in the radial direction. The wedge 20 is disposed in the groove 14. The groove 14 is disposed near both ends or one end of each stator slot 12 in the axial direction.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a rotating electric machine and a drive system for driving a moving object. [Background technology]

[0002] A rotating electric machine includes a stator and a rotor disposed opposite the stator with a gap therebetween. The stator is composed of a stator core having a plurality of slots and a plurality of teeth, and stator windings housed in the slots. Typically, the slots of the stator core have grooves on both circumferential sides, and magnetic or non-magnetic wedges are disposed in the grooves to prevent the stator windings from falling out of the slots.

[0003] When the stator core has grooves on the side of the slots, the width of the teeth is narrowed at the grooves, making it difficult for the magnetic flux generated by the stator winding and the magnetic flux generated by the rotor's field source to pass through. Such rotating electric machines have the problem of leakage magnetic flux from the stator core, reducing the torque relative to the current. In addition, when the width of the teeth is large, the width of the slot is narrowed, reducing the cross-sectional area of ​​the stator winding and increasing the resistance of the stator winding. Such rotating electric machines have the problem of increased copper loss generated by passing current through the stator winding, reducing the torque.

[0004] An example of a technique for solving these problems is disclosed in Patent Document 1. In the armature disclosed in Patent Document 1, a core-side engagement portion including a concave portion that engages with a wedge is partially formed on a part of the side surface of the tooth in the stator core. Since the concave portions that engage with the wedge are discretely arranged on the side surface of the tooth, it is possible to reduce the area where the width of the tooth is narrow (groove portion), preventing a decrease in torque. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2019-97329 A Summary of the Invention [Problem to be solved by the invention]

[0006] From the standpoint of the strength required to prevent the stator windings from falling out of the slots and ease of manufacturing the stator, it is preferable that the wedges for preventing the stator windings from falling out be positioned in grooves on both side sides of the slot by being inserted into the slot from the axial direction.

[0007] In the armature described in Patent Document 1, the concave portions (grooves) that engage with the wedges are provided discretely in the axial direction on the side surfaces of the teeth, so the wedges cannot be inserted into the slots from the axial direction. If the wedges are inserted from the radial direction, they must be plastically deformed to be placed, and the strength required to prevent the stator winding from falling out of the slots may not be sufficient. As represented by the armature described in Patent Document 1, conventional rotating electric machines have a problem in preventing the stator winding from falling out and obtaining a large torque.

[0008] An object of the present invention is to provide a rotating electric machine which can prevent the stator windings from falling off the slots and can obtain large torque. [Means for solving the problem]

[0009] A rotating electric machine according to the present invention comprises a stator having a stator core and a stator winding, and a rotor arranged opposite the stator with a gap therebetween and having a rotatable shaft extending in the axial direction. The stator core comprises a plurality of stator slots extending in the axial direction and accommodating the stator winding, and wedges installed in openings of the stator slots to hold the stator winding. The stator slots have grooves extending in the axial direction on both circumferential side surfaces. The wedges are arranged in the grooves. The grooves are arranged in each of the stator slots, close to both ends or one end in the axial direction.

[0010] A drive system according to the present invention is provided in a moving body, and includes the rotating electric machine according to the present invention, and the rotating electric machine drives the moving body. Effect of the Invention

[0011] According to the present invention, it is possible to provide a rotating electric machine which can prevent the stator winding from falling off the slots and can obtain a large torque. [Brief description of the drawings]

[0012] [Figure 1] 1 is a view showing a cross section along an axial direction of a rotating electric machine according to a first embodiment of the present invention. [Diagram 2] 1 is a diagram showing a cross section perpendicular to the axial direction of a rotating electric machine according to a first embodiment. [Figure 3A] FIG. 2 is a diagram showing a stator core A among the stator cores. [Figure 3B] FIG. 2 is a diagram showing a stator core B among the stator cores. [Figure 4] 1 is a diagram showing a cross section along the axial direction of a stator included in a rotating electric machine according to a first embodiment. [Figure 5A] FIG. 11 is an enlarged view of a portion in the circumferential direction of a stator in a rotary electric machine according to a second embodiment of the present invention, showing a stator slot provided in a stator core A. [Figure 5B] FIG. 11 is an enlarged view of a portion in the circumferential direction of a stator in a rotary electric machine according to a second embodiment of the present invention, showing a stator slot provided in a stator core B. [Figure 5C] FIG. 11 is an enlarged view of a portion of a stator in the circumferential direction in a rotating electric machine according to a second embodiment of the present invention, showing a stator slot provided in a stator core B and a support plate having a width greater than the width of the stator slot. [Figure 6] 11 is a diagram showing a cross section along the axial direction of a stator included in a rotary electric machine according to a second embodiment. FIG. [Figure 7A] FIG. 11 is an enlarged view of a portion in the circumferential direction of a stator in a rotary electric machine according to a third embodiment of the present invention, showing a stator core C among the stator cores. [Figure 7B] FIG. 11 is an enlarged view of a portion in the circumferential direction of a stator in a rotary electric machine according to a third embodiment of the present invention, showing a stator core D among the stator cores. [Figure 8] 11 is a diagram showing a cross section taken along the axial direction of a stator included in a rotary electric machine according to a third embodiment. FIG. [Figure 9] 13A and 13B are diagrams illustrating an example of a wedge in a rotating electric machine according to a fourth embodiment of the present invention. [Figure 10] FIG. 11 is a block diagram showing a configuration of an electric vehicle equipped with a rotating electric machine in a fifth embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] A rotating electric machine according to the present invention includes a stator having a stator core and a stator winding. The stator core includes stator slots that house the stator winding, and wedges that are installed in the stator slots and hold the stator winding. The stator slots include grooves on both circumferential sides, and wedges are disposed in the grooves. The grooves are disposed near both axial ends or one end of the stator slot. That is, in one stator slot, the grooves and wedges are provided only at both axial ends or only at one axial end.

[0014] According to the present invention, the wedge can prevent the stator winding from falling out of the stator slot. Furthermore, since the magnetic saturation of the teeth of the stator core can be alleviated and leakage flux can be reduced, a large torque can be obtained even with a small rotating electric machine, which contributes to the miniaturization of the rotating electric machine.

[0015] Hereinafter, a rotating electric machine and a drive system according to an embodiment of the present invention will be described with reference to the drawings. In the following embodiment, an example will be described in which the rotating electric machine is a permanent magnet synchronous motor. The rotating electric machine according to the present invention can also be applied to an induction motor, a wound field type synchronous motor, and a synchronous reluctance type synchronous motor.

[0016] Hereinafter, the extension direction of the shaft of a rotor included in a rotating electric machine is referred to as the axial direction, the radial direction of the shaft is referred to as the radial direction, and the rotation direction of the shaft is referred to as the circumferential direction.

[0017] In addition, in the drawings referred to in this specification, the same or corresponding components are denoted by the same reference numerals, and repeated description of these components may be omitted. EXAMPLES

[0018] First Embodiment A rotating electric machine according to a first embodiment of the present invention will be described.

[0019] 1 is a diagram showing a cross section along the axial direction of a rotating electric machine 1 according to this embodiment. The rotating electric machine 1, which is a permanent magnet synchronous motor, includes a stator 2 and a rotor 3. The rotor 3 is disposed so as to face the stator 2 with a gap therebetween.

[0020] The stator 2 includes a stator core 4, a polyphase stator winding 5, and a housing 11. The stator core 4 is held on the inner circumferential surface of the housing 11. The stator winding 5 is wound around the stator core 4.

[0021] The rotor 3 includes a rotor core 7, end plates 15, a shaft 8, and bearings 10. The rotor core 7 is fixed and held axially by the end plates 15 at both axial ends. The shaft 8 is fixed to the rotor core 7, extends in the axial direction, and is rotatable. When the shaft 8 rotates, the rotor core 7 rotates in the circumferential direction. The bearings 10 are supported by end brackets 9, and hold the shaft 8 rotatably. The end brackets 9 are fixed to a housing 11.

[0022] The rotor core 7 has a plurality of rotor slots 6 in which permanent magnets 13 are installed. The permanent magnets 13 are axially supported at both axial ends by end plates 15. The rotor core 7 and the end plates 15 have axial ducts 17 penetrating therethrough in the axial direction to reduce the weight of the rotor 3.

[0023] 2 is a diagram showing a cross section perpendicular to the axial direction of the rotating electric machine 1 according to this embodiment. As shown in FIG.

[0024] As described above, the stator 2 includes the stator core 4 and the stator winding 5 , and the stator winding 5 is wound around the stator core 4 .

[0025] The stator core 4 includes a stator yoke portion 21, a plurality of stator teeth portions 22, a plurality of stator slots 12, and a plurality of wedges 20.

[0026] The stator yoke portion 21 is a cylindrical member.

[0027] Stator teeth 22 protrude radially inward from the inner circumferential surface of stator yoke 21. The multiple stator teeth 22 are arranged at equal intervals in the circumferential direction along the inner circumferential surface of stator yoke 21 and extend in the axial direction.

[0028] The stator slots 12 are located between adjacent stator teeth 22, extend in the axial direction, and accommodate the stator windings 5. The stator slots 12 extend from one end to the other end in the axial direction of the stator core 4, and have an opening that opens radially inward, and a wedge 20 is provided in this opening.

[0029] The wedges 20 are axially extending members that are installed at the openings of the stator slots 12 and secure the stator windings 5 ​​in the stator slots 12 to prevent the stator windings 5 ​​from falling out into the gap between the stator 2 and the rotor 3.

[0030] The rotor core 7 of the rotor 3 is formed by laminating multiple electromagnetic steel sheets. Permanent magnets 13 are installed in the rotor slots 6 provided in the rotor core 7. The rotor core 7 includes an axial duct 17 and a hole that passes through in the axial direction and in which the shaft 8 is installed.

[0031] The rotating electric machine 1 according to this embodiment operates as an electric motor when the rotor 3 rotates in a clockwise or counterclockwise direction.

[0032] In the rotating electric machine 1 according to this embodiment, the stator core 4 includes two types of stator cores, that is, a stator core A and a stator core B.

[0033] 3A and 3B are enlarged views showing a part of the stator 2 in the circumferential direction of the rotating electric machine 1 according to this embodiment.

[0034] 3A is a diagram showing a stator core A41 of the stator core 4. The stator core A41 has a plurality of stator teeth 22 protruding radially inward from the inner circumferential surface of the stator yoke portion 21, and a plurality of stator slots 12 located between adjacent stator teeth 22. The stator slots 12 have grooves 14, and wedges 20 are disposed in the grooves 14. In the stator core A41, the grooves 14 are provided on both circumferential side surfaces of the stator slots 12. It is preferable that all of the stator slots 12 in the stator core A41 have the grooves 14.

[0035] Groove 14 is a recess that protrudes in the circumferential direction from the circumferential side surface of stator slot 12, extends in the axial direction, and has wedges 20 disposed therein. Wedge 20 is inserted in groove 14 from the axial direction and disposed in stator slot 12 to hold stator winding 5 in stator slot 12. If the circumferential length is taken as the width, the width of wedge 20 is equal to or greater than the width of stator slot 12.

[0036] The shape of the grooves 14 can be determined arbitrarily. It is preferable that the stator slot 12 has grooves 14 on both side surfaces that are symmetrical to each other in the circumferential direction. In other words, it is preferable that the two grooves 14 on both side surfaces of the stator slot 12 in the circumferential direction have symmetrical shapes with respect to a plane that passes through the center of the stator slot 12 in the circumferential direction and is parallel to the radial and axial directions.

[0037] The radial position of the groove 14 can be determined arbitrarily. For example, the radial position of the groove 14 can be determined at a position where the wedge 20 can fit into the groove 14 and the wedge 20 can hold the stator winding 5 in the stator slot 12.

[0038] 3B is a diagram showing stator core B42 of stator core 4. Like stator core A41, stator core B42 has a plurality of stator teeth 22 and a plurality of stator slots 12. However, unlike stator core A41, stator core B42 does not have grooves 14 on both circumferential side surfaces of stator slot 12, and no wedges 20 are arranged.

[0039] Fig. 4 is a diagram showing a cross section along the axial direction of the stator 2 included in the rotating electric machine 1 according to this embodiment. The housing 11 and the rotor 3 are not shown in Fig. 4. The stator core 4 includes a stator core A41 and a stator core B42 aligned in the axial direction.

[0040] The stator core A41 is disposed close to both axial ends of the stator 2. That is, the stator core A41 is disposed only at both axial ends of the stator 2. The stator core B42 is disposed in the center of the stator 2 in the axial direction.

[0041] Therefore, each stator slot 12 of the stator core 4 has grooves 14 arranged close to both axial ends, wedges 20 are arranged in the grooves 14, and no grooves 14 are arranged in the axial center. That is, in each stator slot 12 of the stator core 4, the grooves 14 and the wedges 20 are arranged only at both axial ends, and not at the axial center.

[0042] The wedges 20 for holding the stator winding 5 are arranged only on the stator core A41. Since the stator core A41 is arranged only on both axial ends, the wedges 20 can be inserted axially into the grooves 14 and arranged in the stator slots 12. Even if the wedges 20 are arranged only on the stator core A41 and not on the stator core B42, the stator winding 5 can be prevented from falling off the stator slots 12 by adjusting, for example, the axial lengths of the stator cores A41 and B42. The axial lengths of the stator cores A41 and B42 can be determined arbitrarily so as to prevent the stator winding 5 from falling off.

[0043] The axial length of the groove 14 is preferably equal to the axial length of the stator core A41.

[0044] The axial length of wedge 20 is approximately the same as the axial length of groove 14, and may or may not be equal to the axial length of groove 14. If the axial length of wedge 20 is longer than the axial length of groove 14, wedge 20 protrudes in the axial direction from the end of stator core 4, making installation and replacement of wedge 20 easy.

[0045] In the rotating electric machine 1 according to this embodiment, the stator core 4 includes a stator core A41 arranged close to both axial ends and a stator core B42 arranged only in the axial center, and a wedge 20 arranged in a groove 14 of the stator core A41 holds the stator winding 5. The wedge 20 can prevent the stator winding 5 from falling out of the stator slot 12.

[0046] In the rotating electric machine 1 according to this embodiment, the stator core B42 does not have the groove 14 for arranging the wedge 20, and therefore the stator core 4 does not have the groove 14 in the axial center portion. Therefore, the rotating electric machine 1 according to this embodiment can reduce leakage magnetic flux from the stator core 4 and can increase torque. EXAMPLES

[0047] An electric rotating machine according to Embodiment 2 of the present invention will be described. Hereinafter, the electric rotating machine according to the present embodiment will be mainly described with respect to the differences from the electric rotating machine according to Embodiment 1.

[0048] FIGS. 5A to 5C are diagrams showing an enlarged view of a part in the circumferential direction of the stator 2 in the electric rotating machine 1 according to the present embodiment, and are diagrams showing the stator slots 12.

[0049] FIG. 5A is a diagram showing the stator slots 12 provided in the stator core A41. As described in Embodiment 1, the stator slots 12 provided in the stator core A41 are provided with grooves 14 on both side surfaces in the circumferential direction. Wedges 20 are arranged in the grooves 14. The wedges 20 are inserted into the grooves 14 from the axial direction and arranged in the stator slots 12.

[0050] In the electric rotating machine 1 according to the present embodiment, in the stator slot 12, a support plate 51 which is a plate-like member is installed between the stator winding 5 and the wedge 20 in the radial direction. The support plate 51 is placed on the wedge 20, functions as a spacer, and holds the stator winding 5 in the stator slot 12. The support plate 51 can be made of a non-magnetic material, for example, the same material as the wedge 20.

[0051] When the circumferential length is taken as the width, the width W2 of the support plate 51 is smaller than the width W1 of the wedge 20 (W2 < W1) and is equal to or less than the width W0 of the stator slot 12 (W2 ≦ W0).

[0052] FIG. 5B is a diagram showing the stator slots 12 provided in the stator core B42. As described in Embodiment 1, the stator slots 12 provided in the stator core B42 are not provided with grooves 14 on both side surfaces in the circumferential direction, and no wedges 20 are arranged.

[0053] In the stator slot 12, a support plate 51 is installed between the opening of the stator slot 12 and the stator winding 5 in the radial direction. The support plate 51 holds the stator winding 5 in the stator slot 12. As described above, the width W2 of the support plate 51 is equal to or less than the width W0 of the stator slot 12 (W2 ≦ W0).

[0054] The width W2 of the support plate 51 may be larger than the width W0 of the stator slot 12 (W2>W0). In the stator core A41, the support plate 51 having such a width W2 is placed on the wedge 20 and arranged in the groove 14. In the stator core B42, this support plate 51 is installed as follows.

[0055] FIG. 5C is a diagram showing the stator slot 12 provided in the stator core B42, and shows the support plate 51 having a width W2 which is larger than the width W0 of the stator slot 12.

[0056] The stator core B42 has grooves 54 on both circumferential side surfaces of the stator slot 12. The grooves 54 are recesses that protrude in the circumferential direction from the circumferential side surfaces of the stator slot 12, extend in the axial direction, and have support plates 51 disposed therein. The width (circumferential length) of the grooves 54 is smaller than the width of the grooves 14 (FIG. 5A) in which the wedges 20 are disposed in the stator core A41.

[0057] Fig. 6 is a diagram showing a cross section along the axial direction of the stator 2 included in the rotating electric machine 1 according to this embodiment. In Fig. 6, the housing 11 and the rotor 3 are not shown.

[0058] As described in the first embodiment (FIG. 4), the stator core 4 includes a stator core A41 and a stator core B42 aligned in the axial direction. The stator core A41 is disposed close to both axial ends of the stator 2. The stator core B42 is disposed in the axial center of the stator 2. Wedges 20 for holding the stator windings 5 ​​are disposed only in the stator core A41, and can be inserted into the grooves 14 from the axial direction and disposed in the stator slots 12.

[0059] The support plate 51 is positioned from one end to the other end in the axial direction of the stator core 4, and is inserted from the axial direction and disposed in the stator slots 12.

[0060] In the stator core 4 having the stator core B42 shown in FIG. 5B, the support plate 51 is supported by wedges 20 arranged at both axial ends, and this supporting force supports the stator winding 5 in the axial center portion.

[0061] In the stator core 4 having the stator core B42 shown in FIG. 5C, the support plate 51 is supported by wedges 20 arranged at both axial ends and a groove 54 arranged in the center, and this supporting force supports the stator winding 5 in the axial center.

[0062] The axial length of support plate 51 is approximately the same as the axial length of stator core 4, and may or may not be equal to the axial length of stator core 4. If the axial length of support plate 51 is longer than the axial length of stator core 4, support plate 51 protrudes in the axial direction from the end of stator core 4, making installation and replacement of support plate 51 easy.

[0063] In the rotating electric machine 1 according to this embodiment, the stator core 4 is provided with a support plate 51 , and the wedge 20 and the support plate 51 can prevent the stator windings 5 ​​from falling out of the stator slots 12 .

[0064] In the rotating electric machine 1 according to this embodiment, even if the stator core 4 does not have a groove 14 for positioning a wedge 20 in the axial center, but has a groove 54 for positioning a support plate 51 in the axial center, the width of groove 54 is smaller than the width of groove 14, so that leakage magnetic flux can be reduced and torque can be increased. EXAMPLES

[0065] A rotating electric machine according to a third embodiment of the present invention will be described below. The following mainly describes the differences between the rotating electric machine according to this embodiment and the rotating electric machine according to the first embodiment.

[0066] In the rotating electric machine 1 according to this embodiment, the stator core 4 includes two types of stator cores, that is, a stator core C and a stator core D.

[0067] 7A and 7B are enlarged views showing a part of the stator 2 in the circumferential direction of the rotating electric machine 1 according to this embodiment.

[0068] 7A is a diagram showing stator core C43 of stator core 4. Stator core C43 has, as stator slots 12, stator slots 12a having grooves 14 and stator slots 12b having no grooves 14. Stator slot 12a has grooves 14 on both circumferential side surfaces, and wedges 20 are arranged in grooves 14.

[0069] The stator slots 12a having the grooves 14 and the stator slots 12b not having the grooves 14 are adjacent to each other in the circumferential direction. That is, the stator core C43 has the stator slots 12a having the grooves 14 and the stator slots 12b not having the grooves 14 alternately in the circumferential direction.

[0070] 7B is a diagram showing stator core D44 of stator core 4. Like stator core C43, stator core D44 has, as stator slots 12, stator slots 12a with grooves 14 and stator slots 12b without grooves 14. A wedge 20 is disposed in groove 14 of stator slot 12a. Stator slot 12a with groove 14 and stator slot 12b without groove 14 are adjacent to each other in the circumferential direction.

[0071] Stator core D44 differs from stator core C43 in the circumferential positions of stator slots 12a that have grooves 14 and stator slots 12b that do not have grooves 14. That is, in stator core C43 and stator core D44, the positions of stator slots 12a that have grooves 14 are shifted from each other in the circumferential direction by one stator slot 12.

[0072] Fig. 8 is a diagram showing a cross section along the axial direction of the stator 2 included in the rotating electric machine 1 according to this embodiment. The housing 11 and the rotor 3 are not shown in Fig. 8. The stator core 4 includes a stator core C43 and a stator core D44 aligned in the axial direction.

[0073] The stator core C43 is disposed near one axial end of the stator 2. That is, the stator core C43 is disposed only at one axial end of the stator 2. The stator core D44 is disposed near the other axial end of the stator 2. That is, the stator core D44 is disposed only at the other axial end of the stator 2.

[0074] In the stator cores C43 and D44, the axial length of the grooves 14 of the stator slots 12a is preferably equal to the axial length of the stator cores C43 and D44, respectively.

[0075] As described above, in stator core C43 and stator core D44, the positions of the stator slots 12a having grooves 14 are shifted from each other in the circumferential direction by one stator slot 12. In Fig. 8, the position of the stator slot 12a having grooves 14 shown in stator core C43 differs in the circumferential direction from the position of the stator slot 12a having grooves 14 shown in stator core D44 by one stator slot 12.

[0076] The wedges 20 for holding the stator winding 5 are arranged only in the stator slots 12a having the grooves 14. Thus, at one axial end of the stator core 4, the wedges 20 are arranged in every other stator slot 12 in the circumferential direction, and at the other axial end, the wedges 20 are arranged in every other stator slot 12 in the circumferential direction that is different from the one end. That is, the grooves 14 and the wedges 20 are arranged alternately in the circumferential direction at one axial end and the other axial end of the stator slots 12 in the stator core 4.

[0077] In each stator slot 12 of the stator core 4, the groove 14 is disposed near one end in the axial direction, and a wedge 20 is disposed in the groove 14. In each stator slot 12 of the stator core 4, the groove 14 and the wedge 20 are disposed only at one end in the axial direction (the one end or the other end), and are not disposed at the other axial end. Therefore, there are stator slots 12 in which the groove 14 and the wedge 20 are disposed near one end in the axial direction, and stator slots 12 in which the groove 14 and the wedge 20 are disposed near the other end in the axial direction.

[0078] The stator core 4 has these two types of stator slots 12 alternately in the circumferential direction. That is, the stator core 4 has stator slots 12 in which the grooves 14 and wedges 20 are arranged close to one axial end and stator slots 12 in which the grooves 14 and wedges 20 are arranged close to the other axial end, alternately in the circumferential direction.

[0079] The wedge 20 is inserted into the groove 14 in the axial direction and disposed in the stator slot 12. That is, the wedge 20 is inserted into one axial end of the stator slot 12 in which the groove 14 is disposed closer to one axial end, and the wedge 20 is inserted into the other axial end of the stator slot 12 in which the groove 14 is disposed closer to the other axial end.

[0080] In the rotating electric machine 1 according to this embodiment, the grooves 14 and wedges 20 arranged in the stator slots 12 are alternately positioned in the circumferential direction at one end and the other end in the axial direction. The wedges 20 hold the stator winding 5 and prevent the stator winding 5 from falling out of the stator slots 12.

[0081] Furthermore, the rotating motor 1 according to this embodiment has stator slots 12 with grooves 14 only at one axial end, and stator slots 12 with grooves 14 only at the other end, so that leakage magnetic flux from the stator core 4 can be reduced and torque can be increased. EXAMPLES

[0082] A rotating electric machine according to a fourth embodiment of the present invention will be described below. The following mainly describes the differences between the rotating electric machine according to this embodiment and the rotating electric machine according to the third embodiment.

[0083] The rotating electric machine 1 according to this embodiment differs from the rotating electric machine 1 according to the third embodiment in the configuration of the wedge 20.

[0084] In the rotating electric machine 1 according to the third embodiment, wedges 20 are arranged in the stator slots 12 every other one in the circumferential direction at one axial end (or the other end) of the stator core 4. That is, at one axial end, the stator slots 12 in which the wedges 20 are arranged (stator slots 12a having grooves 14) and the stator slots 12 in which the wedges 20 are not arranged (stator slots 12b not having grooves 14) are adjacent to each other in the circumferential direction.

[0085] In the rotating electric machine 1 according to this embodiment, a part of the wedge 20 is disposed in the stator slot 12a having the groove 14, and another part of the wedge 20 is disposed in the stator slot 12b having no groove 14.

[0086] 9 is a diagram showing an example of the wedge 20 in the rotating electric machine 1 according to this embodiment. The wedge 20 includes a wedge portion 20b, a support plate portion 20c, and a connection portion 20a.

[0087] The wedge portion 20b is a portion that extends in the axial direction and is disposed in the stator slot 12a having the groove 14, and plays the role of the wedge 20 in Example 3. That is, the wedge portion 20b is disposed in the groove 14 of the stator slot 12a.

[0088] The support plate portion 20c extends in the axial direction and is disposed in the stator slot 12b that does not have a groove 14, and plays the role of the support plate 51 described in the second embodiment. That is, the support plate portion 20c is disposed in the stator slot 12b, and is not disposed in the groove 14.

[0089] The connecting portion 20a extends in the circumferential direction and is a portion that connects the wedge portion 20b and the support plate portion 20c to each other.

[0090] When the length in the circumferential direction is taken as the width, the width W3 of the wedge portion 20b is equal to or greater than the width W0 of the stator slot 12 (W3 ≧ W0). The width W4 of the support plate portion 20c is smaller than the width W3 of the wedge portion 20b (W4 < W3) and is equal to or less than the width W0 of the stator slot 12 (W4 ≦ W0). Since the support plate portion 20c is arranged in the stator slot 12b that does not have the groove 14, the width W4 is smaller than the width W3 of the wedge portion 20b.

[0091] The rotating electrical machine 1 according to this embodiment includes such a wedge 20 and can hold the stator winding 5 more firmly, so that it is possible to more effectively prevent the stator winding 5 from falling out of the stator slot 12, and the reliability of the rotating electrical machine 1 can be improved.

Embodiment

[0092] A drive system according to Embodiment 5 of the present invention will be described. The drive system according to this embodiment is, for example, a drive system used for driving a moving body and includes at least one of the rotating electrical machines described in Embodiments 1 to 4. Hereinafter, as an example, it is assumed that the moving body is an electric vehicle, and the drive system provided in the electric vehicle will be described.

[0093] FIG. 10 is a block diagram showing the configuration of an electric vehicle 100 including a rotating electrical machine 1. The electric vehicle 100 includes a vehicle body 200, wheels 110, 112, 114, 116, a drive system 160, and a steering wheel 150.

[0094] The vehicle body 200 is supported by four wheels 110, 112, 114, 116. In this embodiment, since the electric vehicle 100 is front-wheel drive, the rotating electrical machine 1 is attached to the front axle 154.

[0095] The drive system 160 includes a rotating electric machine 1, a battery 140, and a control device 130, and drives an electric vehicle 100, which is a moving body. The driving torque of the rotating electric machine 1 is controlled by the control device 130. The battery 140 is a power source for the control device 130. The control device 130 receives power from the battery 140 and controls the rotating electric machine 1. The rotating electric machine 1 is driven by the control device 130 using power from the battery 140 to rotate the wheels 110, 114.

[0096] The rotating electric machine 1 is the rotating electric machine 1 described in the first to fourth embodiments, and therefore can apply a large torque to the wheels 110, 114 to drive the electric vehicle 100.

[0097] When the steering wheel 150 is rotated, it changes the direction of the wheels 110, 114 and changes the direction of travel of the electric vehicle 100.

[0098] In this embodiment, an example has been described in which the rotating electric machine 1 described in the first to fourth embodiments drives the wheels 110, 114 of the electric vehicle 100. The rotating electric machine 1 described in the first to fourth embodiments can be used to drive the wheels of not only the electric vehicle 100 but also other electric vehicles such as electric locomotives.

[0099] The drive system according to the present embodiment includes the rotating electric machine 1 described in the first to fourth embodiments, and therefore can provide a large torque to the electric automobile 100 or an electric vehicle even if the rotating electric machine 1 is small. Therefore, according to the present embodiment, it is possible to provide a small and lightweight electric automobile 100 or an electric vehicle.

[0100] The present invention is not limited to the above-described embodiments, and various modifications are possible. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to an embodiment having all of the configurations described. It is also possible to replace a part of the configuration of one embodiment with the configuration of another embodiment. It is also possible to add the configuration of another embodiment to the configuration of one embodiment. It is also possible to delete a part of the configuration of each embodiment, or to add or replace another configuration. [Explanation of symbols]

[0101] Reference Signs List 1... rotating machine, 2... stator, 3... rotor, 4... stator core, 5... stator winding, 6... rotor slot, 7... rotor core, 8... shaft, 9... end bracket, 10... bearing, 11... housing, 12... stator slot, 12a... stator slot with groove, 12b... stator slot without groove, 13... permanent magnet, 14... groove, 15... end plate, 17... axial duct, 20... wedge, 20a... connection connection portion, 20b...wedge portion, 20c...support plate portion, 21...stator yoke portion, 22...stator teeth portion, 41...stator core A, 42...stator core B, 43...stator core C, 44...stator core D, 51...support plate, 54...groove, 100...electric vehicle, 110, 112, 114, 116...wheels, 130...control device, 140...battery, 150...steering wheel, 154...axle, 160...drive system, 200...vehicle body.

Claims

1. a stator including a stator core and a stator winding; a rotor disposed opposite the stator with a gap therebetween and including a rotatable shaft extending in an axial direction; Equipped with the stator core includes a plurality of stator slots extending in the axial direction and housing the stator windings, and wedges disposed in openings of the stator slots and holding the stator windings; The stator slot has grooves on both circumferential sides extending in the axial direction, The wedge is disposed in the groove, The grooves are arranged toward both ends or one end of each of the stator slots in the axial direction. A rotating electric machine characterized by:

2. each of the stator slots has grooves disposed near both ends and no grooves in the axial center; The rotating electric machine according to claim 1 .

3. the stator slots include a first stator slot in which the groove is disposed closer to one of the one ends, and a second stator slot in which the groove is disposed closer to the other one end, the first stator slots and the second stator slots are alternately arranged in the circumferential direction in the stator core, The rotating electric machine according to claim 1 .

4. the two grooves provided on both side surfaces in the circumferential direction of the stator slot are shaped symmetrically with respect to a plane that passes through a center in the circumferential direction of the stator slot and is parallel to the radial direction and the axial direction; The rotating electric machine according to claim 1 .

5. The stator slot includes a plate-like member radially between the stator winding and the wedge, The length of the plate-like member in the circumferential direction is smaller than the length of the wedge in the circumferential direction. The rotating electric machine according to claim 1 .

6. The wedge includes a first portion disposed in the groove of the stator slot, and a second portion disposed in the stator slot adjacent to the stator slot in the circumferential direction in which the first portion is disposed, The circumferential length of the second portion is smaller than the circumferential length of the first portion. The rotating electric machine according to claim 3 .

7. A rotating electric machine according to any one of claims 1 to 6, which is provided in a moving body and drives the moving body. A drive system comprising:

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