JP2007228708A - Rotating electric machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotating electric machine that can lower the height of the coil end of a stator winding. <P>SOLUTION: In the rotating electric machine 100 that comprises a rotor 2 and a stator 1 that is oppositely arranged at the radial outside of the rotor 2, the stator 1 comprises a stator core 11 having a plurality of slots; and the stator winding 6 that serves as a multi-phase winding composed of a coil formed by being arranged in the slot at its one part, and by being joined to a segment conductor 10 protruding from the axial end face of the stator core at its remaining part. Linear parts of even number pieces more than six of the segment conductors 10 are arranged in the slot, and a coil-side interval (front pitch) at a joining side is set smaller than a magnetic pole pitch. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a rotating electrical machine mounted on a passenger car or the like and driven at a high voltage.

A rotating electrical machine having a stator winding constituted by joining U-shaped segment conductors is known, but when such a stator winding is applied to a high-voltage specification on-vehicle motor, Although it depends on the voltage (output), the number of series conductors Z per pole and phase requires 12 to 24. For this purpose, it is necessary to increase the number of slot conductors Nc and the number of slots Ns. As such a stator winding, for example, a stator winding having a slot conductor number Nc of 6 or 8 is known (see Patent Documents 1 to 3).
Japanese Patent No. 3384337 (page 4-8, FIG. 1-11) Japanese Patent No. 3303773 (page 5-9, FIG. 1-19) JP 2004-166316 A (page 15-33, FIG. 1-46)

  However, when the number of slot conductors increases, there is a problem that the coil end height on the bending side (turn portion side) increases. Although the coil end height can be lowered to some extent by devising the arrangement so that the number of segment conductors to be stacked is reduced, the resistance of the stator winding is reduced and the gap between the frames is increased. It is necessary to further reduce the coil end height. Further, in the stator winding having a large number of slot conductors Nc disclosed in the above-mentioned patent document, no particular contrivance is made with respect to the coil end height on the joint side of the segment conductor, and the coil end on the joint side is also low. The idea to do is desired. In addition, since the number of radial joints increases with an increase in the number of slot conductors, there is a problem in that the end of the coil end expands to the outer diameter side and the gap with the frame decreases.

  The present invention was created in view of the above points, and an object of the present invention is to provide a rotating electrical machine capable of reducing the coil end height of a stator winding. Another object of the present invention is to provide a rotating electrical machine capable of reducing the outer diameter of a coil end.

  In order to solve the above-described problems, a rotating electrical machine according to the present invention includes a rotor and a stator disposed opposite to the outer side in the radial direction of the rotor, and the stator extends along the circumferential direction. A stator core formed with a plurality of slots, and a plurality of segments formed by joining segment conductors, one part of which is disposed in the slot and the other one protruding from the axial end surface of the stator core And a stator winding as a multi-phase winding composed of coils, and straight portions of six or more even number of segment conductors are arranged in the slot, which is a joint side coil side interval of a plurality of coils. The front pitch is set smaller than the magnetic pole pitch. Further, it is desirable to set the rear pitch, which is the interval between the anti-joining coil sides of the plurality of coils, smaller than the magnetic pole pitch. Furthermore, it is desirable to set the rear pitch of the inner coil having both coil sides at the center portion in the radial direction of the slot to be smaller than the magnetic pole pitch among the plurality of coils described above. Coil that connects straight portions (coil sides) arranged in two slots in each phase winding by making the coil side pitch of at least a part of each phase winding of the stator winding smaller than the magnetic pole pitch. The end height can be lowered.

  Moreover, it is desirable that the straight portions of the even number of segment conductors arranged in the slots described above are arranged in a line along the radial direction of the stator core. Thereby, the number of segment conductors arranged along the circumferential direction of the stator core can be reduced, and the coil end height can be lowered in combination with the reduction of the coil side pitch interval.

  In addition, it is desirable that the turn portions of at least one pair of segment conductors corresponding to the straight portions arranged at different radial positions in the slot described above intersect along the radial direction of the stator core. The coil end height can be further reduced by crossing the turn portions of the segment conductors without overlapping each other in the height direction of the coil end. Moreover, the expansion of the coil end in the radial direction can be reduced.

  Further, the rotating electrical machine of the present invention has a rotor and a stator disposed opposite to the outer side in the radial direction of the rotor, and the stator has a plurality of slots disposed along the circumferential direction. A multi-phase winding comprising a formed stator core and a plurality of coils formed by joining a segment conductor, a part of which is disposed in the slot and the other one protruding from the axial end surface of the stator core 6 and an even number of segment conductors of straight line portions are arranged in the slot, and each phase winding constituting the stator winding has a plurality of the same connection forms. Is a parallel winding in which four windings are connected in parallel, and an even number of four or more wires are joined together at the end of the segment conductor, and the front pitch or anti-joining that is the coil side spacing of multiple coils The rear pitch, which is the side coil side interval, is It is set to be smaller than that. As a result, the number of joints can be reduced, the expansion of the joint-side coil end to the outer diameter side can be suppressed, and the joining process can be simplified.

  The segment conductor described above is a thick film wire, and it is desirable that no insulating member be interposed between the stator core and the segment conductor and between the segment conductors. As a result, the stator winding can be easily manufactured, and the cost can be reduced and the space factor can be increased.

  Hereinafter, a rotating electrical machine according to an embodiment to which the present invention is applied will be described in detail with reference to the drawings.

[First Embodiment]
FIG. 1 is a cross-sectional view showing the overall structure of the rotating electrical machine of the first embodiment. As shown in FIG. 1, the rotating electrical machine 100 of this embodiment includes a stator 1, a rotor 2, a front bearing 3, a rear bearing 4, and a frame 5.

  The stator 1 includes a cylindrical stator core 11 formed with a plurality of slots arranged along the circumferential direction, and a Y-connected multiphase winding (for example, a three-phase winding composed of U, V, and W phases). And a plurality of types of segment conductors 10 constituting the stator winding 6 as a line). The stator core 11 is formed as a laminated core formed by stacking a plurality of laminated steel plates having a predetermined thickness. The stator winding 6 is supplied with power from, for example, an external three-phase inverter control circuit (not shown).

  The rotor 2 is disposed opposite to the inner side of the stator 1, and a permanent magnet is incorporated therein. A shaft (rotating shaft) 7 of the rotor 2 is rotatably supported by a front bearing 3 and a rear bearing 4. The frame 5 accommodates the front bearing 3 and the rear bearing 4.

  The terminal case 12 incorporates three connection terminals connected to the end portions of the three lead wires 9 drawn from each phase of the stator winding 6. An external three-phase inverter control circuit is connected to these connection terminals. The lead wire 9 drawn out from the terminal case 12 extends parallel to the axis of the shaft 7 and is then bent radially inward and further bent parallel to the axis to be positioned on the radial side of the segment conductor 10. Then, the lead wire for the lead wire 8 drawn out from the outermost layer of the slot is combined in the radial direction, and both axial ends are connected by welding. The weld is covered with an insulating resin 13.

  In the present embodiment, the stator winding 6 is inserted through each slot of the stator core 11 from one axial end face side of the stator core 11 with a rectangular U-shaped segment conductor 10 having a square cross section. The protruding end portion of each segment conductor 10 is projected from the slot to the other axial end face side of the stator core 11 by a necessary length, and the protruding end portion of each segment conductor 10 is twisted in the circumferential direction. It is comprised by joining the front-end | tip part (joining part) of 10 protrusion end parts by welding by a predetermined combination.

  Next, details of the stator winding 6 of this embodiment will be described. In the present embodiment, the stator winding 6 has a six-layer slot conductor structure in which the slot conductor number Nc is six. FIG. 2 is a diagram showing a coil end shape of the stator winding 6 as viewed from the turn portion side of the segment conductor 10, and shows a state in which the outer segment conductor 10 is partially omitted. FIG. 3 is a perspective view showing the connection state of the segment conductors. FIG. 4 is a schematic view of windings for one phase and one pole pair, where the number of slots Ns per phase per pole is two.

  As shown in FIG. 2, the stator winding 6 of the present embodiment has a single-layer conductor on the innermost slot side and a six-layer conductor on the outermost slot side in order to reduce the coil end height of the entire circumference. (In FIG. 4, the reference numerals 1 to 6 attached to the rectangular frames indicate these layer numbers), the 2-4 layer conductor, and the 3-5 layer conductor are bent ( The turn portion side) is connected so as to cross in the radial direction at the coil end portion, and is surrounded by a bending side coil end portion that connects the first to sixth layer conductors. As shown in FIG. 3, the 1st to 6th layer conductors have a conductor arrangement in which all the layers are connected in one cycle, and the 2nd to 4th layer conductors, and the 3rd to 5th layer conductors are overlapped portions, A 1-6 layer conductor comprises a wave winding part.

  As shown in FIG. 4, with respect to the pole pitch Pp = 6 (unit: slot), the coil side pitch (rear side between the second and fourth layer conductors and between the third and fifth layer conductors) of the inner coil (rear side) The pitch is 5 and the coil side pitch (front pitch) on the welding (joining) side is 5, which is one pitch smaller than the pole pitch Pp. As apparent from FIGS. 2 to 4, the height of the U-shaped segment conductor 10 inserted into the slot becomes higher as the circumferential positions of the two linear portions housed in different slots are separated. This is because the number of other segment conductors 10 disposed between the two linear portions increases as the distance between the two linear portions increases. Therefore, as shown in FIG. 4, the segment conductor 10 having a pitch smaller than the pole pitch Pp (= 6) has a lower height on both the bending side and the joining side than the segment conductor having the same pitch as the pole pitch Pp. It becomes possible.

  On the other hand, the coil side pitch of the outer coil (bending side between the 1st layer and 6th layer conductors) is 7, which is one pitch larger than the pole pitch Pp. However, as shown in FIG. The tip portion is brought close to the conductor shape so that the tip bending shape is optimized.

  By adopting such a shape of the segment conductor, the coil end height on the bending side and the joining side can be made lower than that of the full-pitch winding in which the coil side pitch is the same as the pole pitch Pp (= 6). it can. Further, among the deformed wires for connecting adjacent slot conductors (wires having different coil side pitches and bent side shapes), the deformed wires connecting the 1-layer to 5-layer conductors having a large pitch of 7 are shown in FIG. The coil end height can be lowered by making it close to other coils.

  As described above, in the rotating electrical machine 100 according to the present embodiment, at least a part of the coil side pitch of each phase winding of the stator winding 6 is made smaller than the magnetic pole pitch, so that The coil end height connecting the linear portions arranged in the slot can be reduced.

  The segment conductor 10 has a U-shape, and the stator winding 6 is configured by joining ends of different segment conductors 10 to each other and connecting them in series. Thereby, at least one of the coil side pitch (rear pitch) on the turn side (bending side) or the coil side pitch (front pitch) on the joint side of the U-shaped segment conductor 10 can be made smaller than the magnetic pole pitch. The coil end height formed by the turn portion or the coil end height on the joint portion side can be reduced.

  The straight portions of the even number of segment conductors 10 arranged in the slots are arranged in a line along the radial direction of the stator core 11. Thereby, the number of the segment conductors 10 arranged along the circumferential direction of the stator core 11 can be reduced, and the coil end height can be lowered in combination with the reduction of the coil side pitch interval.

  Further, the turn portions of at least one set of segment conductors 10 corresponding to the straight portions arranged at different radial positions in the slot intersect along the radial direction of the stator core 21. Thus, the coil end height can be further reduced by intersecting the turn portions of the segment conductors 10 without overlapping each other in the height direction of the coil end. Further, the outer diameter of the coil end can be made smaller than the case where the turn portions are arranged in an overlapping manner, and the distance from the frame 5 is increased.

  FIG. 5 is a winding schematic diagram of a modified example of the stator winding of the present embodiment, showing a winding schematic diagram of one phase and one pole pair with the number of slots Ns per phase per pole being three. ing. For the pole pitch Pp = 9 (unit: slot), the coil side pitch (rear pitch) of the inner coil (bending side between the 2nd and 4th layer conductors and between the 3rd and 5th layer conductors) is 8, welding side The coil side pitch (front pitch) is 8 and the segment conductor 10 is smaller by 1 pitch. On the other hand, the coil side pitch (rear pitch) of the outer coil (bending side between the 1st and 6th layer conductors) is 10 which is 1 pitch larger than the pole pitch Pp, but the height is lowered as shown in FIG. The inner end of the inner coil is brought close to the tip so that the bent shape of the tip is optimized. By adopting such a shape of the segment conductor 10, the coil end heights on the bending side and the joining side are set to be all-node windings (coil side pitch = coil side pitch = pitch = 9). 9) can be lower. Further, among the deformed wires for connecting adjacent slot conductors, the deformed wire connecting the 1-layer to 5-layer conductor having a large pitch of 11, as shown in FIG. Reduce. In accordance with this, the odd-shaped wire of pitch 9 (between the first layer and fifth layer conductors) is also brought close to other coils to suppress the coil end height.

  FIG. 6 is a side view of the stator winding 6 on the bending side of the segment conductor 10. As shown in FIG. 6, the adjacent slot conductors are connected by a deformed wire 6a whose top portion projects in the axial direction to simplify the connection.

  FIG. 7 is a side view showing a modified example of the stator winding 6. As shown in FIG. 7, by extending the end of each phase of the three-phase winding to the slot outer diameter side (core back side) and connecting at a position shifted from the top of the bending side of the segment conductor 10, The protruding height of the neutral point connecting portion can be suppressed from H0 shown in FIG. 7 to H1 shown in FIG.

[Second Embodiment]
Next, the rotating electrical machine of the second embodiment provided with the stator winding 6 with the slot conductor number Nc of 8 will be described. Note that the overall configuration of the rotating electrical machine of the present embodiment is the same as that of the rotating electrical machine 100 of the first embodiment shown in FIG. 1, and description of the overall configuration is omitted, and only the winding structure is described. And

  FIG. 8 is a diagram showing the coil end shape of the stator winding 6 as viewed from the turn portion side of the segment conductor 10 of the second embodiment, and shows a state in which the outer segment conductor 10 is partially omitted. ing. FIG. 9 is a perspective view showing the connection state of the segment conductors. FIG. 10 is a schematic diagram of windings for one phase and one pole pair, where the number of slots Ns per phase per pole is three. FIG. 11 is a diagram illustrating a coil end shape of the stator winding 6 as viewed from the joint portion side of the segment conductor 10.

  As shown in FIG. 8, in the case of an 8-layer slot conductor (Nc = 8), the 3-layer-5-layer conductor and 4-layer-6-layer conductor are bent side coil end portions in order to reduce the coil end height of the entire circumference. In this structure, the bending side coil end portion connecting the first layer-7 layer conductor and the second layer-8 layer conductor surrounds the periphery. These 1-layer-7-layer conductors and 2-layer-8-layer conductors are also connected so as to intersect in the radial direction at the bending side coil end portion.

  As shown in FIG. 9, each of the conductors from the first layer to the eighth layer has a conductor arrangement in which all layers are connected in one circuit, and the three-layer to five-layer conductor and the four-layer to six-layer conductor are overlapped portions. The 1-layer-7 layer conductor and the 2-layer-8 layer conductor constitute the wave winding portion. As shown in the figure, it is configured as a parallel winding in which adjacent conductors are wound in parallel, and is characterized by being able to cope with a large current. Moreover, as shown in FIG. 11, the adjacent conductor ends are aligned in parallel by welding the joint-side conductor end portions aligned in the radial direction four by one (1 to 4 layer conductors and 5 to 8 layer conductors) together. Connected. Thereby, the number of joining locations can be reduced, the expansion of the joining side coil end to the outer diameter side can be suppressed, and the joining process can be simplified.

  As shown in FIG. 10, the stator winding of the present embodiment is a segment in which the coil side pitch on the welding side is 9 and the coil side pitch on the bending side is 8 with respect to the pole pitch Pp = 9 (unit: slot). It has a conductor shape. Since the coil side pitch on the welding side is 9, the coil end height on the joining side does not change, but the bending side is the coil side of the inner coil (bending side between the 3-5 layers, 4 layers-6 layers conductor) Both the pitch and the coil side pitch of the outer coil (bending side between the first layer-7 layer and the second layer-8 layer conductor) are 8 and can be made smaller than the pole pitch 9, and the coil end on the bending side The height can be made lower than a full-pitch winding in which the coil side pitch is the same as the pole pitch Pp (= 9).

  Further, since the coil side pitch of the inner coil and the outer coil is equal, the bending-side coil forming performed by twisting the two straight portions of the U-shaped segment conductor 10 in the circumferential direction by the coil side pitch The segment conductor 10 corresponding to the coil and the segment conductor 10 corresponding to the outer coil can be performed at a time, and there is an advantage that the stator winding 6 can be easily manufactured.

  Also, as shown in FIG. 10, among the deformed wires for connecting adjacent slot conductors, the deformed wire B connecting the 1st layer-5th layer conductor having a large bending side pitch of 10 and the 2nd layer-6th layer conductor. The coil end height can be suppressed by bringing it close to the deformed wire A (bending side coil side pitch = 7) indicated by a circle in the drawing. Since the adjacent slot conductors are connected by these deformed wires A and B, the three-phase connection portion (not shown) can be simplified and the entire stator winding 6 can be made compact.

  FIG. 12 is a winding schematic diagram showing a modification of the stator winding 6 of the present embodiment. The number of slots Ns per pole per phase is set to 3 as in the stator winding shown in FIG. A variation is shown.

  As shown in FIG. 12, the stator winding 6 of this modification has a coil side pitch of 8 on the welding side and a coil side pitch of the bending side inner coil of 7 with respect to the pole pitch Pp = 9 (unit: slot). The bent side outer coil has a segment conductor shape with a coil side pitch of 9. The outer coil side pitch is the same as the pole pitch Pp, but the tip bending shape is optimized, and the tip is brought close to the inner coil as shown in FIG. 12 to reduce the bending side coil end height. By setting it as such a segment conductor shape, the coil end height of a bending side and a joining side can be made lower than a full joint winding (coil side pitch = 9). Further, among the deformed wires for connecting the adjacent slot conductors, the 1-layer-5 layer conductor having a large bending side coil side pitch of 10 and the deformed wire B connecting the 2-layer-6 layer conductor have a bent end shape. The coil end height is suppressed by optimizing it and bringing it close to the deformed wire A2 having a bending side coil side pitch of 8. Similarly, the shape of the deformed wire A2 is also optimized at the tip bending shape and is brought close to the deformed wire A1 (bending side coil side pitch = 6) indicated by a circle in FIG. 10 to suppress the coil end height.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention. For example, in the above-described embodiment, the segment conductor (flat wire) may be a thick coated wire having a film thickness of 100 μm or more in which the outer periphery of the insulating layer is usually covered with PPS. Thereby, the partial (corona) discharge by a high voltage can be suppressed without using the insulator arrange | positioned around the segment conductor 10. FIG. In addition, when short turns are used as in the above-described embodiments, different phase conductors are wound in the same slot. Therefore, in a conventional rectangular wire, in order to ensure insulation between the different phase conductors, a gap between them is ensured. Although it is desirable to interpose insulating paper, the use of thick coated wires can eliminate the insulating paper between them, and there are advantages such as ease of manufacture, cost reduction, and high space factor.

It is sectional drawing which shows the whole structure of the rotary electric machine of 1st Embodiment. It is a figure which shows the coil end shape of the stator coil | winding seen from the turn part side of the segment conductor. It is a perspective view which shows the connection state of a segment conductor. FIG. 5 is a schematic view of a winding for one phase and one pole pair, where the number of slots Ns per phase per phase is two. It is a winding schematic diagram of the modification of the stator winding | coil of 1st Embodiment. It is a side view of the stator winding | coil of the bending side of a segment conductor. It is a side view which shows the modification of a stator winding | coil. It is a figure which shows the coil end shape of the stator coil | winding seen from the turn part side of the segment conductor of 2nd Embodiment. It is a perspective view which shows the connection state of a segment conductor. FIG. 5 is a schematic view of a winding for one phase and one pole pair, where the number of slots Ns per phase per phase is three. It is a figure which shows the coil end shape of the stator coil | winding seen from the junction part side of the segment conductor. It is a coil | winding schematic diagram which shows the modification of the stator coil | winding of 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Stator 2 Rotor 3 Front bearing 4 Rear bearing 5 Frame 6 Stator winding 10 Segment conductor 11 Stator core 12 Terminal case 100 Rotating electric machine

Claims (7)

In a rotating electrical machine having a rotor and a stator disposed opposite to the outer side in the radial direction of the rotor,
The stator includes a stator core formed with a plurality of slots arranged along a circumferential direction, a part of the stator core is disposed in the slot, and the other one projects from an axial end surface of the stator core. A stator winding as a multiphase winding composed of a plurality of coils formed by joining segment conductors,
In the slot, six or more even-numbered straight portions of the segment conductors are arranged,
A rotating electric machine characterized in that a front pitch, which is a joint-side coil side interval of the plurality of coils, is set smaller than a magnetic pole pitch. In claim 1,
A rotating electrical machine characterized in that a rear pitch, which is an interval between coil sides on the anti-joining side of the plurality of coils, is set smaller than a magnetic pole pitch. In claim 2,
The rotating electrical machine characterized by setting the said back pitch of the inner coil which has both coil sides in the radial direction center part of the said slot among these coils, smaller than a magnetic pole pitch. In any one of Claims 1-3,
The rotating electrical machine according to claim 1, wherein the straight portions of the even number of segment conductors arranged in the slot are arranged in a line along a radial direction of the stator core. In claim 4,
A rotating electric machine characterized in that at least one pair of turn portions of the segment conductors corresponding to straight portions arranged at different radial positions in the slot intersect along the radial direction of the stator core. . In a rotating electrical machine having a rotor and a stator disposed opposite to the outer side in the radial direction of the rotor,
The stator includes a stator core formed with a plurality of slots arranged along a circumferential direction, a part of the stator core is disposed in the slot, and the other one projects from an axial end surface of the stator core. A stator winding as a multiphase winding composed of a plurality of coils formed by joining segment conductors,
In the slot, six or more even-numbered straight portions of the segment conductors are arranged,
Each phase winding constituting the stator winding is a parallel winding in which a plurality of windings having the same connection form are connected in parallel, and four or more even numbers are joined together at the end of the segment conductor. And
A rotating electrical machine characterized in that a front pitch, which is a joint-side coil side interval of the plurality of coils, or a rear pitch, which is an anti-join side coil side interval, is set smaller than a magnetic pole pitch. In any one of Claims 1-6,
The rotating electrical machine, wherein the segment conductor is a thick film wire.

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