CN112953041B

CN112953041B - Stator of rotating electric machine

Info

Publication number: CN112953041B
Application number: CN202011413309.5A
Authority: CN
Inventors: 宫崎将吾; 井上雅志
Original assignee: Honda Motor Co Ltd
Current assignee: Honda Motor Co Ltd
Priority date: 2019-12-10
Filing date: 2020-12-03
Publication date: 2024-04-12
Anticipated expiration: 2040-12-03
Also published as: JP2021093840A; JP7118946B2; CN112953041A

Abstract

Provided is a stator of a rotating electrical machine capable of reducing losses in coils while achieving high output and high torque of the rotating electrical machine. Legs of eight segment conductors arranged in a radial direction are inserted into a plurality of slots of a stator of a rotating electric machine, respectively. The diagonal portion of the first leg and the diagonal portion of the second leg are inclined in the same direction in either the first direction or the second direction in the circumferential direction, and the diagonal portion of the third leg and the diagonal portion of the fourth leg are inclined in the direction opposite to the diagonal direction of the diagonal portion of the first leg and the diagonal portion of the second leg in the circumferential direction. The diagonal portion of the fifth leg and the diagonal portion of the sixth leg are diagonal in the same direction in either the first direction or the second direction in the circumferential direction, and the diagonal portion of the seventh leg and the diagonal portion of the eighth leg are diagonal in a direction opposite to the diagonal direction of the diagonal portion of the fifth leg and the diagonal portion of the sixth leg in the circumferential direction.

Description

Stator of rotating electric machine

Technical Field

The present invention relates to a stator of a rotating electrical machine, and more particularly, to a stator of a rotating electrical machine including coils each having a plurality of segment conductors inserted into each slot.

Background

Conventionally, a stator of a rotating electrical machine is known, which includes: a stator core; and coils of each of the U-, V-, and W-phases, each of which is composed of a plurality of segment conductors inserted in a plurality of slots formed in the circumferential direction of the stator core in a row in the radial direction.

For example, patent document 1 discloses a stator of a four-layer two-parallel rotary electric machine in which a segment conductor is inserted into a slot in a row of four layers in the radial direction, and coils of each of U-, V-, and W-phases are each configured by connecting two windings in parallel.

For example, patent document 2 discloses a stator of an eight-layer two-parallel rotary electric machine in which a segment conductor is inserted into a slot in a row of eight layers in the radial direction, and coils of each of U-, V-, and W-phases are connected in parallel with two windings.

Prior art literature

Patent literature

Patent document 1: japanese patent application laid-open No. 2012-029370

Patent document 2: japanese patent application laid-open No. 2015-023670

Disclosure of Invention

Problems to be solved by the invention

In the stator of the four-layer two-parallel rotary electric machine of patent document 1, since the number of segment conductors inserted into the slots is small, the aspect ratio represented by the radial thickness of the conductor portion of the segment conductors/the circumferential width of the conductor portion can be easily increased. When the aspect ratio is increased, a large current can flow through the segmented conductor, and thus high output and high torque can be achieved, while eddy current loss generated in the segmented conductor increases, and thus there is a problem that loss in the coil increases.

The stator of the eight-layer two-parallel rotary electric machine of patent document 2 has smaller eddy current loss generated in the segment conductors than the stator of the four-layer two-parallel rotary electric machine of patent document 1. However, since the number of segment conductors inserted into the slots is large, there are problems in that the aspect ratio of the segment conductors is small, a large current cannot flow through the segment conductors, and it is difficult to achieve high output and high torque.

The present invention provides a stator of a rotating electrical machine capable of reducing losses in a coil while achieving high output and high torque of the rotating electrical machine.

Means for solving the problems

The present invention provides a stator of a rotating electrical machine, comprising:

a stator core having a substantially annular shape and including a plurality of teeth protruding radially inward at predetermined intervals in a circumferential direction and a plurality of slots which are spaces between the teeth adjacent to each other in the circumferential direction; and

a coil having a plurality of segment conductors respectively inserted into a plurality of the slots,

each of the segment conductors has a leg portion disposed inside the slot and extending substantially linearly in the axial direction,

an axial one end portion of the leg portion protrudes outward from an axial one end face of the stator core, and is formed with a diagonal portion extending diagonally in the circumferential direction in the first direction or the second direction, and a tip portion extending axially outward from a tip of the diagonal portion,

The leg portions of eight segment conductors arranged in a radial direction are inserted into the plurality of slots, respectively, wherein,

when viewed from the one end face side in the axial direction of the stator core,

the leg portions of the eight segment conductors inserted into the slots in a row in the radial direction have, from the radial inner side, a first leg portion arranged in a first layer, a second leg portion arranged in a second layer, a third leg portion arranged in a third layer, a fourth leg portion arranged in a fourth layer, a fifth leg portion arranged in a fifth layer, a sixth leg portion arranged in a sixth layer, a seventh leg portion arranged in a seventh layer, and an eighth leg portion arranged in an eighth layer,

the diagonal portion of the first leg portion and the diagonal portion of the second leg portion are diagonal in the same direction in the circumferential direction in either the first direction or the second direction,

the diagonal portions of the third leg portion and the diagonal portions of the fourth leg portion are diagonal in a direction opposite to diagonal directions of the diagonal portions of the first leg portion and the diagonal portions of the second leg portion in the first direction and the second direction,

the diagonal portion of the fifth leg portion and the diagonal portion of the sixth leg portion are diagonal in the same direction in the circumferential direction in either the first direction or the second direction,

The diagonal portion of the seventh leg portion and the diagonal portion of the eighth leg portion are diagonal in a circumferential direction on a side opposite to a diagonal direction of the diagonal portion of the fifth leg portion and the diagonal portion of the sixth leg portion.

Effects of the invention

According to the present invention, eight segment conductors are inserted into the slots in a radial direction in a row as viewed from one end face side in the axial direction of the stator core, so that eddy current loss generated in the segment conductors can be reduced, and loss in the coil can be reduced. Further, the diagonal portions of the first leg and the second leg are inclined in the same direction in the circumferential direction in either one of the first direction and the second direction, the diagonal portions of the third leg and the diagonal portions of the fourth leg are inclined in the opposite direction to the diagonal directions of the diagonal portions of the first leg and the diagonal portions of the second leg in the circumferential direction, the diagonal portions of the fifth leg and the diagonal portions of the sixth leg are inclined in the same direction in either one of the first direction and the second direction in the circumferential direction, and the diagonal portions of the seventh leg and the diagonal portions of the eighth leg are inclined in the opposite direction to the diagonal directions of the diagonal portions of the fifth leg and the diagonal portions of the sixth leg, whereby the windings connected in parallel can be easily configured by the first leg and the second leg, the third leg and the fourth leg, the fifth leg and the sixth leg, and the seventh leg. Thus, it is possible to easily construct an eight-layer four-parallel rotating electric machine in which the leg portions of the segment conductors are inserted in a row of eight layers in the radial direction in each slot, and four windings are connected in parallel to each of the U-phase, V-phase, and W-phase, so that a large current can be caused to flow through each phase coil, and high output and high torque can be achieved.

Drawings

Fig. 1 is a view of a stator of a rotating electrical machine according to an embodiment of the present invention as viewed from the radially outer side.

Fig. 2 is a sectional view of a stator of the rotary electric machine of fig. 1 as viewed from an axial direction.

Fig. 3 is a perspective view of a segmented conductor of a stator of the rotary electric machine of fig. 1.

Fig. 4 is an enlarged view of the slot periphery of fig. 2.

Fig. 5 is a perspective view of a stator of the rotating electric machine of fig. 1, as viewed from a first end surface side of the stator core.

Fig. 6 is a view of the segmented conductor, the first holder, and the second holder when the first joint and the second joint of the stator of the rotating electric machine of fig. 1 are formed as viewed from the axial direction.

Fig. 7 is an enlarged perspective view of the periphery of the first joint and the second joint of the stator of the rotating electric machine of fig. 1.

Fig. 8 is a view of the stator of the rotating electrical machine of fig. 1 as viewed in the axial direction from the first end surface side of the stator core.

Fig. 9 is a schematic diagram showing a structure of a coil of a stator of the rotating electric machine of fig. 1.

Fig. 10 is an expanded view showing the structure of a V-phase coil of the stator of the rotating electrical machine of fig. 1.

Fig. 11 is an expanded view showing the configuration of each phase coil of U-phase, V-phase, and W-phase of the stator of the rotating electrical machine of fig. 1.

Fig. 12 is a graph showing a relationship between an aspect ratio of a segment conductor and a coil loss of a stator of the rotating electric machine of fig. 1.

Reference numerals illustrate:

10. stator

20. Stator core

201. First end face (end face)

21. Teeth

22. Slot groove

30. Coil

30U U phase coil

30V V phase coil

30W W phase coil

40. Segmented conductor

401. Conductor part

41. Leg portion

41a first end (one end)

411. First leg portion

412. A second leg part

413. Third leg portion

414. Fourth leg part

415. Fifth leg portion

416. Sixth leg portion

417. Seventh leg part

418. Eighth leg portion

43. Diagonal portion

44. Front end part

451. First joint part

452. Second joint part

50U U phase lead-out wire

50V V phase lead-out wire

50W W phase lead-out wire

51U first U phase outgoing line

51V first V phase outgoing line

51W first W phase outgoing line

52U second U phase outgoing line

52V second V phase outgoing line

52W second W phase outgoing line

61U first U phase bridge (first bridge)

61V first V phase bridge (first bridge)

61W first W phase bridge (first bridge)

62U second U phase bridge (second bridge)

62V second V phase bridge (second bridge)

62W second W phase bridge (second bridge)

Lt radial thickness

Lw circumferential width

Detailed Description

An embodiment of a stator of a rotating electrical machine according to the present invention will be described below with reference to the drawings.

As shown in fig. 1 and 2, a stator 10 of a rotating electrical machine according to the present embodiment includes a substantially annular stator core 20 and a coil 30 assembled to the stator core 20.

In the present specification and the like, for simplicity and clarity of description, the axial direction, the radial direction, and the circumferential direction refer to directions with reference to the center axes CL of the stator 10 and the stator core 20. Further, the axially inner side refers to the central side of the stator 10 in the axial direction, and the axially outer side refers to the side away from the center of the stator 10 in the axial direction.

The stator core 20 has a substantially annular shape, and includes: a plurality of teeth 21 protruding radially inward at predetermined intervals in the circumferential direction; and a plurality of slots 22 as spaces between circumferentially adjacent teeth 21. In the present embodiment, the stator core 20 has 48 teeth 21, and 48 slots 22 are formed. The stator core 20 is formed as a laminated core formed by laminating a plurality of electromagnetic steel plates having a predetermined thickness in the axial direction. The stator core 20 has a first end face 201 and a second end face 202 in the axial direction.

The coil 30 is assembled to the stator core 20, and is formed with a first coil end 31 protruding axially outward from a first end surface 201 of the stator core 20 and a second coil end 32 protruding axially outward from a second end surface 202 of the stator core 20.

The coil 30 has a plurality of segment conductors 40 inserted into 48 slots 22, respectively.

As shown in fig. 3, the segmented conductor 40 is provided with an insulating coating portion 402 on a conductor portion 401 having a substantially rectangular cross section. The segment conductor 40 includes a pair of leg portions 41 extending parallel to each other and having a first end portion 41a and a second end portion 41b, and a bent portion 42 connecting the second end portions 41b of the pair of leg portions 41 to each other, and has a substantially U-shape. The segment conductors 40 are arranged such that the pair of leg portions 41 are inserted into the respective different slots 22 of the stator core 20, the bent portions 42 protrude outward in the axial direction from the second end face 202 of the stator core 20, and the first end portions 41a of the pair of leg portions 41 protrude outward in the axial direction from the first end face 201 of the stator core 20.

The protruding portions of the pair of leg portions 41 protruding outward in the axial direction from the first end surface 201 of the stator core 20 are bent in the circumferential direction of the stator core 20 by rotating relatively in the circumferential direction while holding the tip end portions of the first end portions 41a by a jig, not shown, and approaching the stator core 20 in the axial direction. Thus, the protruding portions of the first end portions 41a of the pair of leg portions 41 form the diagonal portions 43 that are bent and extended in the direction approaching each other or in the direction separating from each other in the circumferential direction of the stator core 20, and the tip end portions of the first end portions 41a held by the jigs, that is, the tip end portions 44 that extend from the tip ends of the diagonal portions 43 to the outside in the axial direction of the stator core 20.

The segmented conductor 40 thus formed has: the diagonal portion 43 is folded and extended around the segment conductor 40A in a direction approaching each other in the circumferential direction of the stator core 20; and the wave-wound segment conductor 40B in which the diagonal portions 43 are bent and extended in the direction away from each other of the stator core 20.

As shown in fig. 4 and 5, the leg portions 41 of the segment conductors 40 are inserted into the slots 22 of the stator core 20 in a row of eight layers in the radial direction. That is, the first leg 411 arranged in the first layer, the second leg 412 arranged in the second layer, the third leg 413 arranged in the third layer, the fourth leg 414 arranged in the fourth layer, the fifth leg 415 arranged in the fifth layer, the sixth leg 416 arranged in the sixth layer, the seventh leg 417 arranged in the seventh layer, and the eighth leg 418 arranged in the eighth layer are inserted into each slot 22 of the stator core 20 from the radially inner side.

The diagonal portions 43 of the first leg 411 and the second leg 412 inserted into the eight-layer leg 41 of each slot 22 of the stator core 20 are inclined counterclockwise in the circumferential direction when viewed from the first end surface 201 side of the stator core 20. The diagonal portions 43 of the third leg 413 and the fourth leg 414 are inclined clockwise in the circumferential direction. The diagonal portions 43 of the fifth leg portion 415 and the sixth leg portion 416 are diagonally clockwise in the circumferential direction. The diagonal portion 43 of the seventh leg 417 and the eighth leg 418 is diagonally counterclockwise in the circumferential direction.

In this way, the diagonal portions 43 of the first to eighth leg portions 411 to 418 are identical in the diagonal direction in the circumferential direction every two layers. Accordingly, the first clamp holding the front end portion of the first end portion 41a of the first leg 411 and the second clamp holding the front end portion of the first end portion 41a of the second leg 412 can be relatively rotated in the circumferential direction in a counterclockwise manner while approaching the stator core 20 in the axial direction by one driving source. Similarly, the third clamp holding the front end portion of the first end portion 41a of the third leg 413 and the fourth clamp holding the front end portion of the first end portion 41a of the fourth leg 414 can be relatively rotated clockwise in the circumferential direction while approaching the stator core 20 in the axial direction by one driving source. The fifth jig holding the front end portion of the first end portion 41a of the fifth leg portion 415 and the sixth jig holding the front end portion of the first end portion 41a of the sixth leg portion 416 can be relatively rotated in the circumferential direction in a clockwise manner while approaching the stator core 20 in the axial direction by one driving source. The seventh clamp holding the front end portion of the first end portion 41a of the seventh leg portion 417 and the eighth clamp holding the front end portion of the first end portion 41a of the eighth leg portion 418 can be relatively rotated in the counterclockwise direction while approaching the stator core 20 in the axial direction by one driving source.

Since the diagonal portions 43 of the first to eighth leg portions 411 to 418 can be formed using the driving sources of half the number (4 in the present embodiment) of the leg portions 41 (8 in the present embodiment) of the segment conductors 40 inserted into the respective slots 22, the manufacturing apparatus for forming the diagonal portions 43 of the first to eighth leg portions 411 to 418 can be simplified, and the manufacturing cost of the stator 10 can be reduced. In the present embodiment, since the third jig and the fourth jig and the fifth jig and the sixth jig are rotated relative to the stator core 20 in the circumferential direction in a clockwise manner, the third jig to the sixth jig may be driven by one driving source. In this case, since the diagonal portions 43 of the first to eighth leg portions 411 to 418 can be formed with three driving sources, the manufacturing cost of the stator 10 can be further reduced.

The front end 44 extending axially outward from the front ends of the diagonal portions 43 of the first leg 411 and the second leg 412 inserted into the slot 22, the front end 44 extending axially outward from the front ends of the diagonal portions 43 of the seventh leg 417 and the eighth leg 418, the front end 44 extending axially outward from the front ends of the diagonal portions 43 of the third leg 413 and the fourth leg 414 inserted into the counterclockwise sixth slot 22, and the front end 44 extending axially outward from the front ends of the diagonal portions 43 of the fifth leg 415 and the sixth leg 416 are arranged in the order of the front end 44 of the first leg 411, the front end 44 of the second leg 412, the front end 44 of the third leg 413, the front end 44 of the fourth leg 414, the front end 44 of the fifth leg 415, the front end 44 of the sixth leg 416, the front end 44 of the seventh leg 417, and the front end 44 of the eighth leg 418 from the radially inward.

Next, as shown in fig. 6, the distal ends 44 of the first leg 411 to the eighth leg 418 aligned in the radial direction are held by the first holder 91 disposed on the counterclockwise side in the circumferential direction and the second holder 92 disposed on the clockwise side in the circumferential direction when viewed from the first end face 201 side of the stator core 20.

The first holder 91 has, when viewed from the first end surface 201 side of the stator core 20: a radially extending first side 911; a second side 912 located radially outward of the first side 911 and extending radially on a substantially same line as the first side 911; a third side surface 913 extending in the circumferential direction so as to face a radially inner side surface of the distal end portion 44 of the first leg portion 411; a fourth side surface 914 extending in the circumferential direction so as to face a radially outer side surface of the front end portion 44 of the eighth leg portion 418; and a wedge 915 formed between a radially outer end 911a of the first side surface 911 and a radially inner end 912b of the second side surface 912.

The wedge 915 protrudes in the circumferential direction from the first side surface 911 and the second side surface 912 to the clockwise side. The wedge 915 includes: a first inclined surface 915a inclined radially outward from a radially outer end 911a of the first side surface 911 and extending circumferentially clockwise; and a second inclined surface 915b inclined radially inward from a radially inner end 912b of the second side surface 912 and extending circumferentially clockwise.

The second clamper 92 has, when viewed from the first end surface 201 side of the stator core 20: a radially extending first side 921; a second side surface 922 located radially outward of the first side surface 921 and extending in a radial direction on a substantially same line as the first side surface 921; a third side surface 923 extending in the circumferential direction so as to face a radially inner side surface of the front end portion 44 of the first leg portion 411; a fourth side surface 924 extending in the circumferential direction so as to face a radially outer side surface of the front end portion 44 of the eighth leg portion 418; and a wedge portion 925 formed between a radially outer end 921a of the first side surface 921 and a radially inner end 922b of the second side surface 922.

The wedge portion 925 protrudes counterclockwise from the first side 921 and the second side 922 in the circumferential direction. The wedge portion 925 includes: a first inclined surface 925a inclined radially outward from a radially outer end 921a of the first side surface 921 and extending circumferentially clockwise; and a second inclined surface 925b inclined radially inward from a radially inner end 922b of the second side surface 922 and extending circumferentially clockwise.

The first holder 91 and the second holder 92 have shapes that are symmetrical in the circumferential direction, that is, line symmetrical about the radial direction as an axis, when viewed from the first end face 201 side of the stator core 20.

The first gripper 91 and the second gripper 92 are gripped between the front end portions 44 of the first leg 411 to the eighth leg 418 that are aligned in the radial direction.

At this time, the first side face 911 of the first holder 91 is opposed to the side face on the counterclockwise side in the circumferential direction of the front end portions 44 of the first to fourth leg portions 411 to 414 that are aligned in the radial direction, and the first side face 921 of the second holder 92 is opposed to the side face on the clockwise side in the circumferential direction of the front end portions 44 of the first to fourth leg portions 411 to 414 that are aligned in the radial direction, as viewed from the first end face 201 side of the stator core 20. The second side 912 of the first holder 91 is opposed to the side of the front end 44 of the fifth to eighth legs 415 to 418 that are aligned in the radial direction on the counterclockwise side in the circumferential direction, and the second side 922 of the second holder 92 is opposed to the side of the front end 44 of the fifth to eighth legs 415 to 418 that are aligned in the radial direction on the clockwise side in the circumferential direction. The wedge 915 of the first holder 91 and the wedge 925 of the second holder 92 are located radially between the front end 44 of the fourth leg 414 and the front end 44 of the fifth leg 415, and are circumferentially opposed to each other. The third side surface 913 of the first holder 91 and the third side surface 923 of the second holder 92 extend in the circumferential direction on substantially the same straight line, and abut or come close to the radially inner side surface of the distal end portion 44 of the first leg 411. The fourth side 914 of the first holder 91 and the fourth side 924 of the second holder 92 extend circumferentially on substantially the same straight line and abut or approach the radially outer side of the tip portion 44 of the eighth leg 418.

The first gripper 91 and the second gripper 92 are moved so as to approach each other in the circumferential direction.

Then, the tip portion 44 of the fourth leg portion 414 abuts against the first inclined surface 915a of the wedge portion 915 of the first holder 91 and the first inclined surface 925a of the wedge portion 925 of the second holder 92. The distal end 44 of the fifth leg 415 is in contact with the second inclined surface 915b of the wedge 915 of the first holder 91 and the second inclined surface 925b of the wedge 925 of the second holder 92.

Then, the first gripper 91 and the second gripper 92 are moved closer to each other in the circumferential direction.

Then, the first inclined surface 915a of the wedge 915 of the first holder 91 and the first inclined surface 925a of the wedge 925 of the second holder 92 press the distal end 44 of the fourth leg 414 radially inward. As a result, as the first holder 91 and the second holder 92 approach each other, the distal end portion 44 of the fourth leg portion 414 is bent and deformed so as to incline inward in the radial direction along the first inclined surface 915a of the wedge portion 915 of the first holder 91 and the first inclined surface 925a of the wedge portion 925 of the second holder 92. The distal end portion 44 of the fourth leg portion 414 is bent and deformed so as to incline inward in the radial direction, and the distal end portion 44 of the third leg portion 413 is pressed inward in the radial direction, whereby the distal end portion 44 of the third leg portion 413 is bent and deformed so as to incline inward in the radial direction. Further, the distal end portion 44 of the third leg portion 413 is bent and deformed so as to incline inward in the radial direction, and the distal end portion 44 of the second leg portion 412 is pressed inward in the radial direction, whereby the distal end portion 44 of the second leg portion 412 is bent and deformed so as to incline inward in the radial direction. Since the distal end portion 44 of the first leg 411 abuts or approaches the third side surface 913 of the first holder 91 and the third side surface 923 of the second holder 92, even if the distal end portion 44 of the second leg 412 is bent and deformed so as to incline inward in the radial direction to press the distal end portion 44 of the first leg 411, the distal end portion 44 of the first leg 411 extends substantially parallel to the axial direction without being bent and deformed (see fig. 7). The distal ends 44 of the first to fourth leg portions 411 to 414 are held by the first and second holders 91 and 92 in a state where the adjacent distal ends 44 are in contact with each other.

At the same time, the second inclined surface 915b of the wedge 915 of the first holder 91 and the second inclined surface 925b of the wedge 925 of the second holder 92 press the distal end 44 of the fifth leg 415 radially outward. As a result, as the first holder 91 and the second holder 92 approach each other, the tip portion 44 of the fifth leg 415 is bent and deformed so as to incline radially outward along the second inclined surface 915b of the wedge 915 of the first holder 91 and the second inclined surface 925b of the wedge 925 of the second holder 92. The distal end 44 of the fifth leg portion 415 is bent and deformed so as to be inclined radially outward, and the distal end 44 of the sixth leg portion 416 is pressed radially outward, whereby the distal end 44 of the sixth leg portion 416 is bent and deformed so as to be inclined radially outward. Further, the distal end portion 44 of the sixth leg portion 416 is bent and deformed so as to be inclined radially outward, and the distal end portion 44 of the seventh leg portion 417 is pressed radially outward, whereby the distal end portion 44 of the seventh leg portion 417 is bent and deformed so as to be inclined radially outward. Since the distal end 44 of the eighth leg 418 is in contact with or in proximity to the fourth side surface 914 of the first holder 91 and the fourth side surface 924 of the second holder 92, even if the distal end 44 of the seventh leg 417 is bent and deformed so as to be inclined radially outward to press the distal end 44 of the eighth leg 418, the distal end 44 of the eighth leg 418 extends substantially parallel to the axial direction without being bent and deformed (see fig. 7). The distal ends 44 of the fifth to eighth leg portions 415 to 418 are held by the first and second holders 91 and 92 in a state where the adjacent distal ends 44 are in contact with each other.

Then, in a state where the adjacent front ends 44 of the first to fourth legs 411 to 414 are brought into contact with each other and the adjacent front ends 44 of the fifth to eighth legs 415 to 418 are brought into contact with each other by the first and second holders 91 and 92, the front ends 44 of the first to second legs 411 and 412, the front ends 44 of the second and third legs 413, and the front ends 44 of the third and fourth legs 413 and 44 of the fifth and sixth legs 415 and 416, the front ends 44 of the sixth and seventh legs 417 and 417, and the front ends 44 of the seventh and eighth legs 418 and 44 are joined by, for example, laser welding. Thereby, the four front end portions 44 forming the first to fourth leg portions 411 to 414 are integrally joined and conducted first joining portions 451, and the four front end portions 44 forming the fifth to eighth leg portions 415 to 418 are integrally joined and conducted second joining portions 452.

In this way, when viewed from the first end face 201 side of the stator core 20, the front end portions 44 of the first leg 411 and the second leg 412 inserted into the slot 22 are aligned in the radial direction with the front end portions 44 of the third leg 413 and the fourth leg 414 inserted into the counterclockwise sixth slot 22, and the front end portions 44 of the seventh leg 417 and the eighth leg 418 inserted into the slot 22 are aligned in the radial direction with the front end portions 44 of the fifth leg 415 and the sixth leg 416 inserted into the counterclockwise sixth slot 22, so that the front end portions 44 of the first leg 411 and the second leg 412 inserted into the slot 22 and the front end portions 44 of the third leg 413 and the fourth leg 414 inserted into the counterclockwise sixth slot 22 can be easily joined using the first holder 91 and the second holder 92 having simple shapes, and the front end portions 44 of the seventh leg 417 and the eighth leg 418 inserted into the slot 22 and the front end portions 44 of the fifth leg 415 and the sixth leg 416 inserted into the counterclockwise sixth slot 22 can be easily joined. Thereby, the first joint 451 and the second joint 452 can be easily formed.

The distal ends 44 of the first leg 411 and the second leg 412 inserted into a part of the slot 22 are joined to each other, but are not joined to the distal ends 44 of the third leg 413 and the fourth leg 414 inserted into different slots 22. Similarly, the distal ends 44 of the third leg 413 and the fourth leg 414 inserted into a part of the slot 22 are joined to each other, but are not joined to the distal ends 44 of the first leg 411 and the second leg 412 inserted into different slots 22. The distal ends 44 of the fifth leg 415 and the sixth leg 416 inserted into a part of the socket 22 are joined to each other, but are not joined to the distal ends 44 of the seventh leg 417 and the eighth leg 418 inserted into a different socket 22. Similarly, the distal ends 44 of the seventh leg 417 and the eighth leg 418 inserted into a part of the slot 22 are joined to each other, but are not joined to the distal ends 44 of the fifth leg 415 and the sixth leg 416 inserted into different slots 22. Details will be described later.

Thus, the coil 30 is constituted by the plurality of segment conductors 40 respectively inserted into the 48 slots 22. The diagonal portion 43 and the tip portion 44 of each segment conductor 40 constitute the first coil end portion 31 of the coil 30, and the bent portion 42 of each segment conductor 40 constitutes the second coil end portion 32 of the coil 30.

Therefore, the stator 10 of the present embodiment includes: a first joint 451 for joining the distal ends 44 of the first leg 411 and the second leg 412 inserted into the slot 22 to the distal ends 44 of the third leg 413 and the fourth leg 414 inserted into the different slot 22; and a second joint 452 that joins the distal ends 44 of the fifth leg 415 and the sixth leg 416 inserted into the socket 22 with the distal ends 44 of the seventh leg 417 and the eighth leg 418 inserted into different sockets 22. That is, in the stator 10 of the present embodiment, the front end portions 44 of the leg portions 41 inserted into the slots 22 of the stator core 20 in a row of eight layers are joined together every four, so that there are two joining portions (first joining portion 451, second joining portion 452) with respect to the eight leg portions 41 inserted into one slot 22.

In the conventional stator, when the legs of the eight-layer segment conductors are inserted into the slots of the stator core in a row in the radial direction to form a coil, the stator includes a first joint portion for joining the distal end portion of the first leg to the distal end portion of the second leg inserted into a different slot, a second joint portion for joining the distal end portion of the third leg to the distal end portion of the fourth leg inserted into a different slot, a third joint portion for joining the distal end portion of the fifth leg to the distal end portion of the sixth leg inserted into a different slot, and a fourth joint portion for joining the distal end portion of the seventh leg to the distal end portion of the eighth leg inserted into a different slot. Therefore, in the conventional stator, the front end portions of the leg portions inserted into the slots of the stator core in a row of eight layers are joined together two by two, so that there are four joint portions with respect to the eight leg portions inserted into one slot.

Therefore, since the conventional stator has four joint portions arranged in the radial direction, it is difficult to increase the radial interval between the four joint portions and to increase the partial discharge start voltage of the coil.

In contrast, in the present embodiment, since the first joint 451 and the second joint 452 are arranged in the radial direction, which are two joints, the radial interval between the joints can be increased, and the partial discharge start voltage of the coil 30 can be increased.

In order to manufacture the conventional stator, it is necessary to provide three or six wedge portions in total between the tip end portion of the second leg portion and the tip end portion of the third leg portion, between the tip end portion of the fourth leg portion and the tip end portion of the fifth leg portion, and between the tip end portion of the sixth leg portion and the tip end portion of the seventh leg portion in the radial direction in the first holder 91 and the second holder 92, respectively. Further, in order to provide three wedge portions on the first holder 91 and the second holder 92, respectively, it is necessary to reduce the size of one wedge portion.

In contrast, in the present embodiment, since the four distal ends 44 of the first leg 411 to the fourth leg 414 are integrally joined and the four distal ends 44 of the fifth leg 415 to the eighth leg 418 are integrally joined, the first holder 91 and the second holder 92 may be provided with the wedge portions 915, 925 between the distal end of the fourth leg and the distal end of the fifth leg in the radial direction, that is, one and a total of two wedge portions 915, 925 may be provided on the first holder 91 and the second holder 92, respectively. Thus, the shapes of the first holder 91 and the second holder 92 can be simplified, and thus the manufacturing cost of the stator 10 can be reduced. Further, since only one wedge 915, 925 need be formed on each of the first gripper 91 and the second gripper 92, the wedges 915, 925 can be made larger. This can increase the rigidity of the first holder 91 and the second holder 92, and thus can reduce the manufacturing cost of the stator 10.

Further, as shown in fig. 7, since the distal end portions 44 of the second to fourth leg portions 412 to 414 are bent so as to incline radially inward and the distal end portions 44 of the fifth to seventh leg portions 415 to 417 are bent so as to incline radially outward, the radial interval between the distal end portions 44 of the fourth and fifth leg portions 414 and 415 becomes large. Thereby, the partial discharge start voltage of the coil 30 becomes high, and generation of partial discharge in the coil 30 can be suppressed, and therefore the coil 30 can be driven with a larger electric power, and the output performance of the rotary electric machine can be improved.

When the distal end portions 44 of the second to fourth leg portions 412 to 414 are bent and deformed inward in the radial direction by the first and second holders 91 and 92, the inclination angle θ3 of the distal end portion 44 of the third leg portion 413 with respect to the axial direction is larger than the inclination angle θ2 of the distal end portion 44 of the second leg portion 412 with respect to the axial direction, and the inclination angle θ4 of the distal end portion 44 of the fourth leg portion 414 with respect to the radial direction is larger than the inclination angle θ3. When the distal end portions 44 of the fifth leg portions 415 to 417 are bent and deformed radially outward by the first and second holders 91 and 92 in this way, the inclination angle θ6 of the distal end portion 44 of the sixth leg portion 416 with respect to the axial radial outward direction is larger than the inclination angle θ7 of the distal end portion 44 of the seventh leg portion 417 with respect to the axial radial outward direction, and the inclination angle θ5 of the distal end portion 44 of the fifth leg portion 415 with respect to the radial outward direction is larger than the inclination angle θ6.

Accordingly, the distal end portion 44 of the fourth leg portion 414 out of the distal end portions 44 of the second to fourth leg portions 412 to 414 is bent so as to be inclined most radially inward, and the distal end portion 44 of the fifth leg portion 415 out of the distal end portions 44 of the fifth to seventh leg portions 415 to 417 is bent so as to be inclined most radially outward, so that the radial interval between the distal end portions of the fourth and fifth segment conductors, that is, the radial interval between the first and second joint portions 451 and 452 can be increased, and the partial discharge start voltage of the coil 30 can be further increased.

Further, since the distal end portion 44 of the first leg 411 and the distal end portion 44 of the eighth leg 418 do not bend radially inward and outward, but extend parallel to the axial direction, the radial distance between the distal end portion of the fourth segment conductor and the distal end portion of the fifth segment conductor can be increased without increasing the radial length of the first coil end portion 31.

< construction of coil based on segmented conductor >

Next, the structure of the coil 30 based on the segment conductors 40 (lap-wound segment conductor 40A and wave-wound segment conductor 40B) inserted into the slots 22 of the stator core 20 will be described.

As shown in fig. 8, the U-phase lead 50, U, V, and W-phase lead 50V, 50W are connected to the coil 30. Is electrically connected to a power conversion device, not shown, or the like. When the rotating electric machine is driven as a motor, U-phase ac power, V-phase ac power, and W-phase ac power, of three-phase ac power supplied from a power conversion device, not shown, are supplied to the coil 30 from the U-phase lead line 50U, V, the W-phase lead line 50V, and the W-phase lead line 50W, respectively. When the rotating electric machine is driven as a generator, U-phase lead line 50U, V, V-phase lead line 50V, and W-phase lead line 50W supply U-phase ac power, V-phase ac power, and W-phase ac power, respectively, of three-phase ac power generated by the rotating electric machine to a power conversion device or the like, not shown.

In the present embodiment, the U-phase lead wire 50U has two lead wires, i.e., a first U-phase lead wire 51U and a second U-phase lead wire 52U. The V-phase lead 50V has two leads, i.e., a first V-phase lead 51V and a second V-phase lead 52V. The W-phase lead wire 50W has two lead wires, i.e., a first W-phase lead wire 51W and a second W-phase lead wire 52W. The first U-phase lead line 51U and the second U-phase lead line 52U, the first V-phase lead line 51V and the second V-phase lead line 52V, and the first W-phase lead line 51W and the second W-phase lead line 52W are electrically connected to the distal end portion 44 of the predetermined segment conductor 40, respectively. Details of which of the front end portions 44 of the segment conductors 40 the first U-phase lead line 51U and the second U-phase lead line 52U, the first V-phase lead line 51V and the second V-phase lead line 52V, and the first W-phase lead line 51W and the second W-phase lead line 52W are electrically connected to will be described later.

The coil 30 is connected to the first U-phase bridge 61U and the second U-phase bridge 62U, the first V-phase bridge 61V and the second V-phase bridge 62V, and the first W-phase bridge 61W and the second W-phase bridge 62W. The first U-phase bridge 61U and the second U-phase bridge 62U, the first V-phase bridge 61V and the second V-phase bridge 62V, and the first W-phase bridge 61W and the second W-phase bridge 62W are conductors, and may or may not be insulated. The first U-phase bridge 61U and the second U-phase bridge 62U, the first V-phase bridge 61V and the second V-phase bridge 62V, and the first W-phase bridge 61W and the second W-phase bridge 62W each extend circumferentially outside the coil 30 in the axial direction, and both ends are electrically connected to the tip ends 44 of the different segment conductors 40, respectively. Details of which of the front end portions 44 of the segment conductors 40 the first U-phase bridge 61U and the second U-phase bridge 62U, the first V-phase bridge 61V and the second V-phase bridge 62V, and the first W-phase bridge 61W and the second W-phase bridge 62W are electrically connected to will be described later.

A neutral point 70 is connected to the coil 30. The neutral point 70 is a conductor and may or may not be insulated. In the present embodiment, the neutral point 70 extends in the circumferential direction on the radially outer side of the coil 30, and is electrically connected to the tip ends 44 of the plurality of segment conductors 40. The details of which of the segment conductors 40 the neutral point 70 is electrically connected to the distal end portion 44 will be described later.

As shown in fig. 9, the coil 30 is constituted by a three-phase coil, i.e., a U-phase coil 30U, V-phase coil 30V, and a W-phase coil 30W. The U-phase coil 30U is electrically connected to the U-phase lead wire 50U. The V-phase coil 30V is electrically connected to the V-phase lead 50V. The W-phase coil 30W is electrically connected to the W-phase lead wire 50W.

The U-phase coil 30U is formed by connecting four windings U1, U2, U3, and U4 in parallel. Each of the windings U1, U2, U3, and U4 has windings U1-1, U2-1, U3-1, and U4-1 wound clockwise and windings U1-2, U2-2, U3-2, and U4-2 wound counterclockwise, respectively, when viewed radially outward from the center axis CL of the stator core 20. One end of the windings U1-1 and U2-1 is electrically connected to the first U-phase lead wire 51U. One end of the windings U3-1, U4-1 is electrically connected to the second U-phase lead line 52U. The other end portions of the windings U1-1, U2-1 are electrically connected to one end portions of the windings U1-2, U2-2 via a first U-phase bridge 61U. The other ends of windings U3-1, U4-1 are electrically connected to one ends of windings U3-2, U4-2 via second U-phase bridge 62U. The other ends of windings U1-2, U2-2 and the other ends of windings U3-2, U4-2 are electrically connected to neutral point 70.

The V-phase coil 30V is formed by connecting four windings V1, V2, V3, V4 in parallel. Each of the windings V1, V2, V3, V4 has a clockwise winding V1-1, V2-1, V3-1, V4-1 and a counterclockwise winding V1-2, V2-2, V3-2, V4-2, respectively, when viewed radially outward from the center axis CL of the stator core 20. One end of the windings V1-1 and V2-1 is electrically connected to the first V-phase lead wire 51V. One end of the windings V3-1 and V4-1 is electrically connected to the second V-phase lead line 52V. The other ends of the windings V1-1, V2-1 are electrically connected to one ends of the windings V1-2, V2-2 via a first V-phase bridge 61V. The other ends of the windings V3-1, V4-1 are electrically connected to one ends of the windings V3-2, V4-2 via a second V-phase bridge 62V. The other ends of the windings V1-2, V2-2 and the other ends of the windings V3-2, V4-2 are electrically connected to the neutral point 70.

The W-phase coil 30W is formed by connecting four windings W1, W2, W3, W4 in parallel. Each of the windings W1, W2, W3, W4 has a clockwise winding W1-1, W2-1, W3-1, W4-1 and a counterclockwise winding W1-2, W2-2, W3-2, W4-2, respectively, when viewed radially outward from the center axis CL of the stator core 20. One end of the windings W1-1 and W2-1 is electrically connected to the first W-phase lead wire 51W. One end of the windings W3-1 and W4-1 is electrically connected to the second W-phase lead wire 52W. The other end portions of the windings W1-1, W2-1 are electrically connected to one end portions of the windings W1-2, W2-2 via the first W-phase bridge 61W. The other ends of the windings W3-1, W4-1 are electrically connected to one ends of the windings W3-2, W4-2 via a second W-phase bridge 62W. The other ends of the windings W1-2, W2-2 and the other ends of the windings W3-2, W4-2 are electrically connected to the neutral point 70.

For simplicity and clarity of explanation, as shown in fig. 2, 48 slots 22 of the stator core 20 are set clockwise as first slots 2201 to 48 th slots 2248 when viewed from the first end face 201 side of the stator core 20.

The structure of V-phase coil 30V among the three-phase coils of U-phase coil 30U, V phase coil 30V, W phase coil 30W constituting coil 30 will be described with reference to fig. 10. In fig. 10, the leg 41 constituting the windings V1 and V2 is shown in dark color (shading of fine dots), and the leg 41 constituting the windings V3 and V4 is shown in light color (shading of rough dots).

As shown in fig. 10, when viewed from the first end surface 201 side of the stator core 20, the second end 41b of the first leg 411 is connected to the second end 41b of the fifth leg 415 inserted into the fifth slot 22 counterclockwise in the circumferential direction by the bent portion 42, and becomes a pair of legs 41 overlapping the segment conductor 40A. The second end 41b of the second leg portion 412 is connected to the second end 41b of the sixth leg portion 416 inserted into the fifth slot 22 in the counterclockwise direction in the circumferential direction by the bent portion 42, and becomes a pair of leg portions 41 of the lap-wound segment conductor 40A. The second end 41B of the third leg 413 is connected to the second end 41B of the seventh leg 417 inserted into the fifth slot 22 in the counterclockwise direction in the circumferential direction by the bent portion 42, and becomes a pair of legs 41 of the wave-wound segment conductor 40B. The second end 41B of the fourth leg 414 is connected to the second end 41B of the eighth leg 418 inserted into the fifth slot 22 in the counterclockwise direction by the bent portion 42, and becomes a pair of legs 41 of the wave-wound segment conductor 40B.

Therefore, the second end 41b of the fifth leg 415 and the second end 41b of the first leg 411 inserted into the fifth slot 22 clockwise in the circumferential direction are connected by the bent portion 42 as viewed from the first end face 201 side of the stator core 20, and become a pair of legs 41 that lap around the segmented conductor 40A. The second end 41b of the sixth leg 416 is connected to the second end 41b of the second leg 412 inserted into the fifth slot 22 clockwise in the circumferential direction by the bent portion 42, and becomes a pair of legs 41 of the lap-wound segment conductor 40A. The second end 41B of the seventh leg 417 is connected to the second end 41B of the third leg 413 inserted into the fifth slot 22 clockwise in the circumferential direction by the bent portion 42, and becomes a pair of legs 41 of the wave-wound segment conductor 40B. The second end 41B of the eighth leg 418 is connected to the second end 41B of the fourth leg 414 inserted into the fifth slot 22 clockwise in the circumferential direction by the bent portion 42, and becomes a pair of legs 41 of the wave-wound segment conductor 40B.

The tip 44 of the seventh leg 417 inserted into the 28 th slot 2228 and the tip 44 of the eighth leg 418 are joined and connected by, for example, laser welding. The tip end 44 of the fifth leg portion 415 inserted into the 22 nd slot 2222 and the tip end 44 of the sixth leg portion 416 are joined and connected by, for example, laser welding. On the other hand, the joined distal ends 44 of the seventh leg 417 and the eighth leg 418 inserted into the 28 th slot 2228 and the joined distal ends 44 of the fifth leg 415 and the sixth leg 416 inserted into the 22 th slot 2222 are arranged in a substantially straight line in the radial direction, but are not joined and are not conductive.

Similarly, the tip portion 44 of the seventh leg portion 417 inserted into the 27 th slot 2227 and the tip portion 44 of the eighth leg portion 418 are joined and conducted by, for example, laser welding. The tip portion 44 of the fifth leg portion 415 inserted into the 21 st slot 2221 and the tip portion 44 of the sixth leg portion 416 are joined and conducted by, for example, laser welding. On the other hand, the joined distal ends 44 of the seventh leg 417 and the eighth leg 418 inserted into the 27 th slot 2227 and the joined distal ends 44 of the fifth leg 415 and the sixth leg 416 inserted into the 21 st slot 2221 are arranged in a substantially straight line in the radial direction, but are not joined and are not conductive.

The tip 44 of the seventh leg 417 inserted into the 21 st slot 2221 and the tip 44 of the eighth leg 418 are joined and connected by, for example, laser welding. In addition, the front end portion 44 of the fifth leg portion 415 inserted into the 15 th slot 2215 and the front end portion 44 of the sixth leg portion 416 are joined and conducted by, for example, laser welding. On the other hand, the joined distal ends 44 of the seventh leg 417 and the eighth leg 418 inserted into the 21 st slot 2221 and the joined distal ends 44 of the fifth leg 415 and the sixth leg 416 inserted into the 15 th slot 2215 are arranged in a substantially straight line in the radial direction, but are not joined and are not conductive.

Similarly, the tip portion 44 of the seventh leg portion 417 inserted into the 22 nd slot 2222 and the tip portion 44 of the eighth leg portion 418 are joined and conducted by, for example, laser welding. In addition, the front end portion 44 of the fifth leg portion 415 inserted into the 16 th slot 2216 and the front end portion 44 of the sixth leg portion 416 are joined and conducted by, for example, laser welding. On the other hand, the joined distal ends 44 of the seventh leg 417 and the eighth leg 418 inserted into the 22 th slot 2222 and the joined distal ends 44 of the fifth leg 415 and the sixth leg 416 inserted into the 16 th slot 2216 are arranged in a substantially straight line in the radial direction, but are not joined and are not conductive.

The tip end portion of the first V-phase lead wire 51V of the V-phase lead wire 50V is joined to and conducted with the joined tip end portions 44 of the seventh leg portion 417 and the eighth leg portion 418 inserted into the 28 th slot 2228 by, for example, laser welding. The tip 44 of the eighth leg 418 inserted into the 28 th slot 2228 serves as the start point of the winding V1-1, and the tip 44 of the seventh leg 417 inserted into the 28 th slot 2228 serves as the start point of the winding V2-1.

The tip end portion of the second V-phase lead 52V of the V-phase lead 50V is joined to and conducted with the joined tip end portions 44 of the seventh leg portion 417 and the eighth leg portion 418 inserted into the 27 th slot 2227 by, for example, laser welding. The tip 44 of the eighth leg 418 inserted into the 27 th slot 2227 serves as the start point of the winding V3-1, and the tip 44 of the seventh leg 417 inserted into the 27 th slot 2227 serves as the start point of the winding V4-1.

Conventionally, when the V-phase coil 30V is configured by connecting four windings V1, V2, V3, and V4 in parallel, the V-phase lead 50V requires four lead wires equal to the number of parallel wires. In the present embodiment, the tip end portion of the first V-phase lead wire 51V of the V-phase lead wire 50V is joined to the joined tip end portions 44 of the seventh leg portion 417 and the eighth leg portion 418 inserted into the 28 th slot 2228, and the tip end portion of the second V-phase lead wire 52V is joined to the joined tip end portions 44 of the seventh leg portion 417 and the eighth leg portion 418 inserted into the 27 th slot 2227. Thus, since the V-phase lead 50V can be connected to the windings V1, V2, V3, and V4 by two lead wires, the number of parallel windings of each phase can be increased from two to four without increasing the number of lead wires of each phase.

Next, the windings V1 (V1-1, V1-2) and V2 (V2-1, V2-2) will be described.

Winding V1-1 is formed such that, starting from front end portion 44 of eighth leg 418 inserted into fourth 28 slot 2228, eighth leg 418 inserted into fourth 28 slot 2228 is connected to fourth leg 414 inserted into fourth 33 slot 2233 through bending portion 42, fourth leg 414 inserted into fourth 33 slot 2233 is connected to second leg 412 inserted into fourth 39 slot 2239 through first joint portion 451, second leg 412 inserted into fourth 39 slot 2239 is connected to sixth leg 416 inserted into fourth 34 slot 2234 through bending portion 42, sixth leg 416 inserted into fourth 34 slot 2214 is connected to eighth leg 418 inserted into fourth 40 slot 2240 through bending portion 42, eighth leg 418 inserted into fourth slot 2245 is connected to fourth leg 414 inserted into fourth 45 slot 2245 through bending portion 42, fourth leg 414 inserted into fourth slot 2245 is connected to fourth leg 412 inserted into third slot 2233 through first joint portion 451, fourth leg 418 is connected to sixth leg 416 through bending portion 220, fourth leg 418 is connected to eighth leg 418 through fourth joint portion 220, fourth leg 2216 is connected to eighth leg 418 through bending portion 220, and eighth leg 418 through fourth joint portion 220 is connected to eighth leg 418 inserted into fourth slot 2240 through fourth joint portion 412, eighth leg 418 through bending portion 220 is connected to eighth leg 418 inserted into fourth slot 2240 through fourth joint portion 220, eighth leg 418 through fourth joint portion 220 and eighth leg 418 inserted into fourth slot 2240, and fourth leg 418 is connected to eighth leg 418 through fourth leg 418 in fourth joint portion 45 slot 45 and fourth leg 2245 through bending portion 45 and fourth leg joint portion 45 to fourth leg 220 and fourth leg 220, the eighth leg 418 inserted into the 16 th slot 2216 is connected to the fourth leg 414 inserted into the 21 st slot 2221 by the bent portion 42, the fourth leg 414 inserted into the 21 st slot 2221 is connected to the second leg 412 inserted into the 27 th slot by the first joint 451, the second leg 412 inserted into the 27 th slot is connected to the sixth leg 416 inserted into the 22 nd slot 2222 by the bent portion 42, and the front end 44 of the sixth leg 416 inserted into the 22 nd slot 2222 is terminated. As a result, the winding V1-1 is wound clockwise around from the tip end 44 of the eighth leg 418 inserted into the 28 th slot 2228 as a start point to the tip end 44 of the sixth leg 416 inserted into the 22 nd slot 2222 as an end point when viewed radially outward from the center axis CL of the stator core 20.

Winding V2-1 is formed such that front end portion 44 of seventh leg portion 417 inserted into fourth slot 2228 is connected to third leg portion 413 inserted into fourth slot 2233 through bending portion 42, seventh leg portion 417 inserted into fourth slot 2228 is connected to third leg portion 413 inserted into fourth slot 33 slot 2233 through bending portion 42, third leg portion 413 inserted into fourth slot 33 slot 2233 is connected to first leg portion 411 inserted into fifth slot 2239 through a first joint portion 451, first leg portion 411 inserted into fourth slot 2239 is connected to fifth leg portion 415 inserted into fifth slot 34 through bending portion 42, fifth leg portion 415 inserted into fifth slot 2214 is connected to seventh leg portion 417 through bending portion 22140 through bending portion 42, seventh leg portion 417 inserted into fifth slot 2240 through bending portion 42 is connected to seventh leg portion 417 inserted into fifth slot 417, seventh leg portion 417 through bending portion 42 is connected to seventh leg portion 417 inserted into fifth slot 2240 through bending portion 2245, third leg portion 411 through bending portion 2243 is connected to fifth leg portion 415 through bending portion 220, and fifth leg portion 220 is connected to seventh leg portion 417 through bending portion 220, and seventh leg portion 417 is connected to seventh leg portion 417 in fifth slot 2214 through bending portion 42 and seventh leg portion 417 inserted into fifth slot 2240, the seventh leg portion 417 inserted into the 16 th slot 2216 is connected to the third leg portion 413 inserted into the 21 st slot 2221 by the bent portion 42, the third leg portion 413 inserted into the 21 st slot 2221 is connected to the first leg portion 411 inserted into the 27 th slot by the first joint portion 451, the first leg portion 411 inserted into the 27 th slot is connected to the fifth leg portion 415 inserted into the 22 nd slot 2222 by the bent portion 42, and the front end portion 44 of the fifth leg portion 415 inserted into the 22 nd slot 2222 is the end point. As a result, the winding V2-1 is wound clockwise around from the front end 44 of the seventh leg 417 inserted into the 28 th slot 2228, which is joined to the first V-phase lead wire 51V as a starting point, to the front end 44 of the fifth leg 415 inserted into the 22 nd slot 2222 as a finishing point, when viewed radially outward from the center axis CL of the stator core 20.

One end of the first V-phase bridge 61V is joined to and in communication with the joined distal ends 44 of the fifth leg 415 and the sixth leg 416 inserted into the 22 th slot 2222, and the other end thereof is joined to and in communication with the joined distal ends 44 of the fifth leg 415 and the sixth leg 416 inserted into the 15 th slot 2215. Accordingly, the joined distal end portions 44 of the fifth leg portion 415 and the sixth leg portion 416 inserted into the 22 th slot 2222 and the joined distal end portions 44 of the fifth leg portion 415 and the sixth leg portion 416 inserted into the 15 th slot 2215 are in communication via the first V-phase bridge 61V.

The tip end 44 of the sixth leg 416 inserted into the 15 th slot 2215, which is joined to the other end of the first V-phase bridge 61V, serves as the start point of the winding V1-2, and the tip end 44 of the fifth leg 415 inserted into the 15 th slot 2215, which is joined to the other end of the first V-phase bridge 61V, serves as the start point of the winding V2-2.

Winding V1-2 is formed such that, starting from front end 44 of sixth leg 416 inserted into fourth slot 2215, sixth leg 416 inserted into fourth slot 2215 is connected to second leg 412 inserted into eighth slot 2200 through bend 42, second leg 412 inserted into fourth slot 2200 is connected to fourth leg 414 inserted into fourth slot 2214 through first joint 451, fourth leg 414 inserted into fourth slot 2214 is connected to eighth leg 418 inserted into ninth slot 2209 through bend 42, eighth leg 418 inserted into ninth slot 2209 is connected to sixth leg 416 inserted into third slot 2203 through bend 452, sixth leg 416 inserted into eighth slot 2203 is connected to second leg 412 inserted into eighth slot 2208 through bend 42, second leg 412 inserted into eighth slot 2208 is connected to fourth leg 414 inserted into fourth slot 2214 through first joint 451, fourth leg 418 is connected to fourth leg 418 through bend 22433 through bend 2244, eighth leg 418 is connected to sixth leg 418 inserted into eighth slot 2233 through bend 2243, sixth leg 418 is connected to sixth leg 416 inserted into eighth slot 2233 through bend 42, sixth leg 418 is connected to sixth leg 418 inserted into eighth slot 2203 through bend 22433, fourth leg 418 is connected to eighth leg 418 inserted into eighth slot 2203 through bend 42, fourth leg 412 inserted into eighth slot 2208 is connected to fourth leg 412 inserted into eighth slot 2204 through bend 22433, fourth leg 418 is connected to fourth leg 414 into fourth slot 2234 through bend 224, the sixth leg 416 inserted into the 27 th slot 2227 is connected to the second leg 412 inserted into the 32 nd slot 2232 by the bent portion 42, the second leg 412 inserted into the 32 nd slot 2232 is connected to the fourth leg 414 inserted into the 26 th slot by the first joint 451, the fourth leg 414 inserted into the 26 th slot is connected to the eighth leg 418 inserted into the 21 st slot 2221 by the bent portion 42, and the front end 44 of the eighth leg 418 inserted into the 21 st slot 2221 is terminated. As a result, the winding V1-2 is wound counterclockwise from the tip end 44 of the sixth leg 416 inserted into the 15 th slot 2215, which is joined to the second V-phase bridge 62V, to the tip end 44 of the eighth leg 418 of the 21 st slot 2221, when viewed radially outward from the center axis CL of the stator core 20.

The winding V2-2 is formed such that the front end portion 44 of the fifth leg 415 inserted into the 15 th slot 2215 is set as a starting point, the fifth leg 415 inserted into the 15 th slot 2215 is connected with the first leg 411 inserted into the 20 th slot 2220 through the bent portion 42, the first leg 411 inserted into the 20 th slot 2220 is connected with the third leg 413 inserted into the 14 th slot 2214 through the first joint 451, the third leg 413 inserted into the 14 th slot 2214 is connected with the seventh leg 417 inserted into the ninth slot 2209 through the bent portion 42, the seventh leg 417 inserted into the ninth slot 2209 is connected with the fifth leg 415 inserted into the third slot 2203 through the second joint 452, the fifth leg 415 inserted into the third slot 2203 is connected with the first leg 411 inserted into the eighth slot 2208 through the bent portion 42, the first leg 411 inserted into the eighth slot 2208 is connected with the third leg 413 inserted into the second slot 2208 through the first joint 451, the third leg portion 413 inserted into the second slot 2202 is connected with the seventh leg portion 417 inserted into the 45 th slot 2245 through the bent portion 42, the seventh leg portion 417 inserted into the 45 th slot 2245 is connected with the fifth leg portion 415 inserted into the 39 th slot 2239 through the second joint portion 452, the fifth leg portion 415 inserted into the 39 th slot 2239 is connected with the first leg portion 411 inserted into the 44 th slot 2244 through the bent portion 42, the first leg portion 411 inserted into the 44 th slot 2244 is connected with the third leg portion 413 inserted into the 38 th slot 2238 through the first joint portion 451, the third leg portion 413 inserted into the 38 th slot 2238 is connected with the seventh leg portion 417 inserted into the 33 th slot 2233 through the bent portion 42, the seventh leg portion 417 inserted into the 33 th slot 2233 is connected with the fifth leg portion 415 inserted into the 27 th slot 2227 through the second joint portion 452, the fifth leg 415 inserted into the 27 th slot 2227 is connected to the first leg 411 inserted into the 32 nd slot 2232 by the bent portion 42, the first leg 411 inserted into the 32 nd slot 2232 is connected to the third leg 413 inserted into the 26 th slot by the first joint 451, the third leg 413 inserted into the 26 th slot is connected to the seventh leg 417 inserted into the 21 st slot 2221 by the bent portion 42, and the front end portion 44 of the seventh leg 417 inserted into the 21 st slot 2221 is terminated. As a result, the winding V2-2 is wound counterclockwise from the front end 44 of the fifth leg 415 inserted into the 15 th slot 2215, which is joined to the second V-phase bridge 62V, to the front end 44 of the seventh leg 417 of the 21 st slot 2221, which is the end point, when viewed radially outward from the center axis CL of the stator core 20.

The joined distal ends 44 of the seventh leg 417 and the eighth leg 418 inserted into the 21 st slot 2221 are joined to the neutral point 70 and are in conduction.

Next, the windings V3 (V3-1, V3-2) and V4 (V4-1, V4-2) will be described.

The winding V3-1 is formed to be wound in the same manner as the winding V1-1 at a position offset counterclockwise by one slot 22 with respect to the winding V1-1 when viewed from the first end face 201 side of the stator core 20. Accordingly, the winding V3-1 starts from the front end 44 of the eighth leg 418 inserted into the 27 th slot 2227 and ends at the front end 44 of the sixth leg 416 inserted into the 21 st slot 2221. The winding V3-1 is wound clockwise around the stator core 20 from the distal end 44 of the eighth leg 418 inserted into the 27 th slot 2227 as a start point to the distal end 44 of the sixth leg 416 inserted into the 21 st slot 2221 as an end point when viewed radially outward from the center axis CL of the stator core.

The winding V4-1 is formed so as to be wound in the same manner as the winding V2-1 at a position offset counterclockwise by one slot 22 with respect to the winding V2-1 when viewed from the first end face 201 side of the stator core 20. Therefore, the winding V4-1 starts from the front end 44 of the seventh leg 417 inserted into the 27 th slot 2227 and ends at the front end 44 of the fifth leg 415 inserted into the 21 st slot 2221. When viewed radially outward from the center axis CL of the stator core 20, the winding V4-1 is wound clockwise around from the tip end 44 of the seventh leg 417 inserted into the 27 th slot 2227 as a start point to the tip end 44 of the fifth leg 415 inserted into the 21 st slot 2221 as a finish point.

One end of the second V-phase bridge 62V is joined to and in communication with the joined distal ends 44 of the fifth leg 415 and the sixth leg 416 inserted into the 21 st slot 2221, and the other end thereof is joined to and in communication with the joined distal ends 44 of the fifth leg 415 and the sixth leg 416 inserted into the 16 th slot 2216. Accordingly, the joined distal end portions 44 of the fifth leg portion 415 and the sixth leg portion 416 inserted into the 21 st slot 2221 and the joined distal end portions 44 of the fifth leg portion 415 and the sixth leg portion 416 inserted into the 16 th slot 2216 are in conduction via the second V-phase bridge 62V.

The tip end 44 of the sixth leg 416 inserted into the 16 th slot 2216, which is joined to the other end of the second V-phase bridge 62V, becomes the start point of the winding V3-2, and the tip end 44 of the fifth leg 415 inserted into the 16 th slot 2216, which is joined to the other end of the second V-phase bridge 62V, becomes the start point of the winding V4-2.

The winding V3-2 is formed so as to be wound in the same manner as the winding V1-2 at a position shifted clockwise by one slot 22 with respect to the winding V1-2 when viewed from the first end face 201 side of the stator core 20. Accordingly, the winding V3-2 starts from the front end 44 of the sixth leg 416 inserted into the 16 th slot 2216 and ends at the front end 44 of the eighth leg 418 inserted into the 22 nd slot 2222. When viewed radially outward from the center axis CL of the stator core 20, the winding V3-2 is wound counterclockwise around from the tip end 44 of the sixth leg 416 inserted into the 16 th slot 2216 as a start point to the tip end 44 of the eighth leg 418 inserted into the 22 nd slot 2222 as an end point.

The winding V4-2 is formed to be wound in the same manner as the winding V2-2 at a position shifted clockwise by one slot 22 with respect to the winding V2-2 when viewed from the first end face 201 side of the stator core 20. Therefore, the winding V4-2 starts from the distal end 44 of the fifth leg 415 inserted into the 16 th slot 2216 and ends at the distal end 44 of the seventh leg 417 inserted into the 22 nd slot 2222. When viewed radially outward from the center axis CL of the stator core 20, the winding V4-2 is wound counterclockwise around from the tip end 44 of the fifth leg 415 inserted into the 16 th slot 2216 as a start point to the tip end 44 of the seventh leg 417 inserted into the 22 nd slot 2222 as an end point.

The engaged tip portions 44 of the seventh leg portion 417 and the eighth leg portion 418 inserted into the 22 nd slot 2222 are engaged with the neutral point 70 and are in conduction.

In this way, the diagonal portions 43 of the first leg 411 and the second leg 412 are inclined in the circumferential direction counterclockwise, the diagonal portions 43 of the third leg 413 and the fourth leg 414 are inclined in the circumferential direction clockwise, the diagonal portions 43 of the fifth leg 415 and the sixth leg 416 are inclined in the circumferential direction clockwise, and the diagonal portions 43 of the seventh leg 417 and the eighth leg 418 are inclined in the circumferential direction counterclockwise, whereby the windings V1 and V2 connected in parallel can be easily configured by the first leg 411 and the second leg 412, the third leg 413 and the fourth leg 414, the fifth leg 415 and the sixth leg 416, and the seventh leg 417 and the eighth leg 418. Thus, the leg 41 of the segment conductor 40 can be easily configured as an eight-layer four-parallel rotating electric machine in which four windings V1, V2, V3, V4 are connected in parallel and which is inserted into each slot 22 in a row of eight layers in the radial direction, and therefore a larger current can be caused to flow through the V-phase coil 30V, and high output and high torque can be achieved.

In the conventional case of forming the V-phase coil 30V by connecting four windings V1, V2, V3, and V4 in parallel, four bridges having the same number as the number of parallel connections are required. In the present embodiment, the four windings V1, V2, V3, and V4 can be connected in parallel by using two bridges, i.e., the first V-phase bridge 61V and the second V-phase bridge 62V. Thus, the four windings can be connected in parallel by the two bridges, and thus the number of parallel windings of each phase can be increased from two to four without increasing the number of bridges of each phase.

The U-phase coil 30U and the W-phase coil 30W have the same configuration as the V-phase coil 30V except that the U-phase coil 30U is offset by four slots 22 counterclockwise from the V-phase coil 30V when viewed from the first end surface 201 side of the stator core 20, as shown in fig. 11, although the detailed description of the configurations of the U-phase coil 30U and the W-phase coil 30W is omitted. The W-phase coil 30W has the same configuration as the V-phase coil 30V except that it is offset by four slots 22 clockwise with respect to the V-phase coil 30V when viewed from the first end face 201 side of the stator core 20.

In fig. 11, U, V, W respectively inserted into the first to eighth leg portions 411 to 418 of the first to 48 th slots 2201 to 2248 denote windings constituting which of the U-, V-, and W-phases are denoted by reference numerals (18U, 25V, 31W, etc.), and the number portion denotes the number of times of connection of the leg portions 41 from the U-phase lead line 50U, V-phase lead line 50V and the W-phase lead line 50W, that is, the connection order of the leg portions 41.

Thus, the windings U1 to U4, V1 to V4, and W1 to W4 are formed by the segment conductors 40 inserted into the slots 22 of the stator core 20, whereby it is possible to construct an eight-layer four-parallel rotating electrical machine in which eight-layer leg portions 41 are inserted into each slot 22 in one row in the radial direction and four windings of each phase are connected in parallel.

< loss in coil >

In general, when a current flows through a coil of a rotating electrical machine, copper loss Wc represented by the following formula (1) is generated by a winding resistance of a winding constituting the coil.

Wc＝R×i ² …(1)

Wc: copper loss [ W ]

R: winding resistance [ omega ]

i: current flowing through winding [ A ]

Therefore, the larger the cross-sectional area of the winding constituting the coil is, the smaller the winding resistance is, and the copper loss Wc decreases in proportion to the winding resistance. In addition, the smaller the current flowing through the winding, the copper loss Wc decreases in proportion to the current flowing through the winding.

In the case of realizing high output and high torque of a rotating electrical machine, one of the methods is to increase the current flowing through the coil. In this case, if the number of windings of the coil connected in parallel is increased, the current flowing through the windings can be divided equally, and therefore, even if the current flowing through the coil is increased, the current flowing through the windings is not increased.

In addition, in the rotating electrical machine, when the rotor rotates, leakage magnetic flux in the circumferential direction flows from the rotor side to the stator core side. When the leakage magnetic flux flows through the conductor portion of the winding constituting the coil, an eddy current is generated in the conductor portion of the winding, and an eddy current loss We represented by the following formula (2) is generated.

We∝f ² Bm ² t ² …(2)

We: eddy current loss [ W ]

f: frequency [ Hz ]

Bm: magnetic flux density [ T ]

t: radial thickness of conductor portion of winding [ m ]

Thus, the smaller the radial thickness of the conductor portion of the winding, the smaller the eddy current loss We is in proportion to the square of the radial thickness of the conductor portion of the winding.

A four-layer two-parallel rotating electrical machine using the same stator core 20 and having four layers of leg portions of a segmented conductor having a radial thickness of about twice the radial thickness of the present embodiment inserted in a row in the radial direction in each slot 22 and two windings of each phase connected in parallel was compared with the copper loss Wc and the eddy current loss We of the eight-layer four-parallel rotating electrical machine of the present embodiment.

For the four-layer two-parallel rotating electric machine, the radial thickness of the leg 41 of the eight-layer four-parallel rotating electric machine of the present embodiment is half of the radial thickness thereof, and therefore the winding resistance R is doubled, but since the number of windings connected in parallel is doubled, the current i flowing in the windings is halved. Therefore, according to the formula (1), the copper loss Wc of the eight-layer four-parallel rotating electric machine of the present embodiment is theoretically about 1/2 of that of the four-layer two-parallel rotating electric machine.

On the other hand, in the four-layer two-parallel rotating electric machine of the present embodiment, the radial thickness of the leg 41 of the eight-layer four-parallel rotating electric machine is half of the radial thickness thereof, and therefore, according to expression (2), the eddy current loss We of the eight-layer four-parallel rotating electric machine of the present embodiment is theoretically about 1/4 of that of the four-layer two-parallel rotating electric machine.

Furthermore, the eddy current loss We becomes larger in proportion to the square of the frequency. Therefore, the higher the rotation speed of the rotating electric machine is, the higher the frequency is, and the eddy current loss We becomes larger in proportion to the square of the frequency. Therefore, when the losses generated in the four-layer two-parallel rotating electric machine in which the leg portions of the segment conductors having a radial thickness of approximately twice that of the present embodiment are inserted in one row in the radial direction in each slot 22 and two windings of each phase are connected in parallel are compared with the losses generated in the eight-layer four-parallel rotating electric machine of the present embodiment, particularly when the rotating electric machine is driven at a higher speed, the losses generated in the eight-layer four-parallel rotating electric machine of the present embodiment can be significantly reduced as compared with the four-layer two-parallel rotating electric machine.

Further, since the heat generation amount of each winding increases in proportion to the current density of the current flowing, it is desirable that the current flowing through each winding is equal to or smaller than the upper limit value of the current having the current density of a predetermined value or less from the viewpoints of heat generation and cooling of the rotating electrical machine. Since the radial thickness of the windings constituting the coils of the four-layer two-parallel rotating electric machine is about twice that of the present embodiment, the upper limit value of the current in which the current density of one winding constituting the coils of the eight-layer four-parallel rotating electric machine is equal to or less than the predetermined value is 1/2 of the upper limit value of the current in which the current density of one winding constituting the coils of the four-layer two-parallel rotating electric machine is equal to or less than the predetermined value. On the other hand, since the four-layer two-parallel rotating electric machine is two-parallel, the current can flow in two halves through the two windings, but since the eight-layer four-parallel rotating electric machine of the present embodiment is four-parallel, the current can flow in four halves through the four windings. That is, in the eight-layer four-parallel rotary electric machine of the present embodiment, the upper limit value of the current in which the current density of one winding is equal to or less than the predetermined value is halved as compared with the four-layer two-parallel rotary electric machine, but the number of windings through which the current can flow in parallel is doubled. Therefore, the current flowing through the coils of the eight-layer four-parallel rotating electrical machine according to the present embodiment can be made substantially equal to the upper limit value of the current that can flow through the coils of the four-layer two-parallel rotating electrical machine.

Next, an eight-layer two-parallel rotating electrical machine using the same stator core 20, in which eight layers of leg portions of a segmented conductor having the same cross section as the present embodiment are inserted in one row in the radial direction in each slot 22, and two windings of each phase are connected in parallel, is compared with the eight-layer four-parallel rotating electrical machine of the present embodiment.

In the eight-layer two-parallel rotating electric machine and the eight-layer four-parallel rotating electric machine of the present embodiment, the eddy current loss We is theoretically substantially the same because the leg portions of eight identical segmented conductors are inserted in one row in the radial direction in each slot 22.

However, when the same current is caused to flow through the coils of the eight-layer two-parallel rotating electric machine and the coils of the eight-layer four-parallel rotating electric machine of the present embodiment, a current approximately twice as large as the current flowing through the coils of the eight-layer four-parallel rotating electric machine of the present embodiment flows through the coils of the eight-layer two-parallel rotating electric machine. That is, since the current flowing through the windings of the coils constituting the eight-layer four-parallel rotating electrical machine of the present embodiment is about 1/2 of the current flowing through the windings of the coils constituting the eight-layer two-parallel rotating electrical machine, the copper loss Wc generated in the eight-layer four-parallel rotating electrical machine of the present embodiment is about 1/2 of the copper loss Wc of the eight-layer two-parallel rotating electrical machine.

Further, since the heat generation amount of each winding increases in proportion to the current density of the current flowing through the winding, it is desirable that the current flowing through each winding is equal to or smaller than the upper limit value of the current having the current density of the predetermined value or less from the standpoint of heat generation and cooling of the rotating electric machine, but since the eight-layer two-parallel rotating electric machine has the segmented conductors having the same cross section as the eight-layer four-parallel rotating electric machine of the present embodiment, the upper limit value of the current having the current density of one winding of the predetermined value or less is the same. On the other hand, since the eight-layer two-parallel rotating electric machine is two-parallel, the current can equally flow through the two windings, and therefore the upper limit value of the current that can flow through the coil so that the current density becomes equal to or lower than the predetermined value is approximately twice the upper limit value of the current that can flow through the one winding so that the current density becomes equal to or lower than the predetermined value. In contrast, since the eight-layer four-parallel rotating electrical machine according to the present embodiment is four-parallel, the current can flow through the four windings in four equal divisions, and therefore the upper limit value of the current flowing through the coil can be approximately four times the upper limit value of the current of one winding, which is equal to or less than the predetermined value, so that the current density becomes equal to or less than the predetermined value. Therefore, the upper limit value of the current that can flow through the coils of the eight-layer four-parallel rotating electrical machine according to the present embodiment is about twice the upper limit value of the current that can flow through the coils of the eight-layer two-parallel rotating electrical machine so that the current density is equal to or lower than the predetermined value. In this way, since the eight-layer four-parallel rotary electric machine of the present embodiment can cause a larger current to flow through the coil than the eight-layer two-parallel rotary electric machine, high output and high torque can be achieved.

In this way, the stator 10 of the eight-layer four-parallel rotary electric machine of the present embodiment can achieve high output and high torque of the rotary electric machine, and can reduce losses generated by the rotary electric machine.

< relation between aspect ratio and coil loss >

The segmented conductor 40 has an insulating coating portion 402 provided on a conductor portion 401 having a substantially rectangular cross section. In the radial thickness Lt of the conductor portion 401 and the circumferential width Lw of the conductor portion 401, the aspect ratio is represented by the radial thickness Lt/the circumferential width Lw. The relationship between the aspect ratio and the coil loss in the present embodiment will be described with reference to fig. 12.

As shown in fig. 12, the copper loss Wc increases as the aspect ratio decreases. On the other hand, the eddy current loss We increases with an increase in aspect ratio. When the aspect ratio is in the range of 0.5 to 0.7, the sum of the copper loss Wc and the eddy current loss We becomes small. In particular, in the range of the aspect ratio of 0.55 or more and 0.65 or less, the sum of the copper loss Wc and the eddy current loss We becomes smaller, and in the range of the aspect ratio of about 0.6, the sum of the copper loss Wc and the eddy current loss We becomes smallest.

The aspect ratio of the radial thickness Lt/circumferential width Lw of the conductor portion 401 of the segmented conductor 40 of the present embodiment is 0.5 to 0.7. Preferably, the aspect ratio expressed by the radial thickness Lt/circumferential width Lw of the conductor portion 401 of the segment conductor 40 is 0.55 or more and 0.65 or less. More preferably, the aspect ratio represented by the radial thickness Lt/circumferential width Lw of the conductor portion 401 of the segmented conductor 40 is 0.6. This can further reduce the loss in the coil 30.

The embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments, and can be modified or improved as appropriate.

For example, in the present embodiment, the segment conductor 40 has a pair of leg portions 41 extending parallel to each other and having a first end portion 41a and a second end portion 41b, and a bent portion 42 connecting the second end portions 41b of the pair of leg portions 41 to each other, and is formed in a substantially U-shape, but the segment conductor 40 may be joined by welding or the like instead of connecting the second end portions 41b of the leg portions 41 by the bent portion 42.

In this specification, at least the following matters are described. Note that, in parentheses, constituent elements and the like corresponding to those in the above embodiment are shown, but the present invention is not limited thereto.

(1) A stator (stator 10) of a rotating electrical machine is provided with:

a stator core (stator core 20) having a substantially annular shape and including a plurality of teeth (teeth 21) protruding radially inward at predetermined intervals in a circumferential direction and a plurality of slots (slots 22) which are spaces between the teeth adjacent to each other in the circumferential direction; and

a coil (coil 30) having a plurality of segment conductors (segment conductors 40) respectively inserted into a plurality of the slots,

Each of the segment conductors has a leg portion (leg portion 41) disposed inside the slot and extending substantially linearly in the axial direction,

one axial end portion (first end portion 41 a) of the leg portion protrudes outward from one axial end surface (first end surface 201) of the stator core, and is formed with a diagonal portion (diagonal portion 43) extending diagonally in a first direction (clockwise direction) or a second direction (counterclockwise direction) in the circumferential direction and a front end portion (front end portion 44) extending axially outward from a front end of the diagonal portion,

the leg portions of the eight segment conductors inserted into the slots in a row in the radial direction have, from the radial inner side, a first leg portion (first leg portion 411) arranged in a first layer, a second leg portion (second leg portion 412) arranged in a second layer, a third leg portion (third leg portion 413) arranged in a third layer, a fourth leg portion (fourth leg portion 414) arranged in a fourth layer, a fifth leg portion (fifth leg portion 415) arranged in a fifth layer, a sixth leg portion (sixth leg portion 416) arranged in a sixth layer, a seventh leg portion (seventh leg portion 417) arranged in a seventh layer, and an eighth leg portion (eighth leg portion 418) arranged in an eighth layer,

According to (1), eight segment conductors are inserted into the slots in a line in the radial direction as viewed from one end face side in the axial direction of the stator core, so that eddy current loss generated in the segment conductors can be reduced, and loss in the coil can be reduced. Further, the diagonal portions of the first leg and the second leg are inclined in the same direction in the circumferential direction in either one of the first direction and the second direction, the diagonal portions of the third leg and the diagonal portions of the fourth leg are inclined in the opposite direction to the diagonal directions of the diagonal portions of the first leg and the diagonal portions of the second leg in the circumferential direction, the diagonal portions of the fifth leg and the diagonal portions of the sixth leg are inclined in the same direction in either one of the first direction and the second direction in the circumferential direction, and the diagonal portions of the seventh leg and the diagonal portions of the eighth leg are inclined in the opposite direction to the diagonal directions of the diagonal portions of the fifth leg and the diagonal portions of the sixth leg, whereby the windings connected in parallel can be easily configured by the first leg and the second leg, the third leg and the fourth leg, the fifth leg and the sixth leg, and the seventh leg. Thus, it is possible to easily construct an eight-layer four-parallel rotating electric machine in which the leg portions of the segment conductors are inserted in a row of eight layers in the radial direction in each slot, and four windings are connected in parallel to each of the U-phase, V-phase, and W-phase, so that a large current can be caused to flow through each phase coil, and high output and high torque can be achieved.

(2) The stator of a rotating electrical machine according to (1), wherein,

the segmented conductor has a conductor portion (conductor portion 401) having a substantially rectangular cross section, and an aspect ratio expressed by a radial thickness (radial thickness Lt)/a circumferential width (circumferential width Lw) of the conductor portion is 0.5 to 0.7.

According to (2), since the segment conductor has the conductor portion having a substantially rectangular cross section and the aspect ratio of the radial thickness/circumferential width of the conductor portion is 0.5 or more and 0.7 or less, the loss in the coil can be further reduced.

(3) The stator of a rotating electrical machine according to (1) or (2), wherein,

the coil has a U-phase coil (U-phase coil 30U), a V-phase coil (V-phase coil 30V), and a W-phase coil (W-phase coil 30W),

the U-phase coil is electrically connected with a U-phase lead wire (U-phase lead wire 50U), the V-phase coil is electrically connected with a V-phase lead wire (V-phase lead wire 50V), and the W-phase coil is electrically connected with a W-phase lead wire (W-phase lead wire 50W),

the U-phase outgoing line has: a first U-phase lead wire (first U-phase lead wire 51U) connected to the distal end portion of the seventh leg portion and the distal end portion of the eighth leg portion inserted into the predetermined slot; and a second U-phase lead wire (second U-phase lead wire 52U) connected to the distal end portion of the seventh leg portion and the distal end portion of the eighth leg portion inserted into the slot different from the predetermined slot,

The V-phase lead wire has: a first V-phase lead wire (first V-phase lead wire 51V) connected to the distal end portion of the seventh leg portion and the distal end portion of the eighth leg portion, the first V-phase lead wire being inserted into the predetermined slot different from the U-phase lead wire; and a second V-phase lead wire (second V-phase lead wire 52V) connected to the distal end portion of the seventh leg portion and the distal end portion of the eighth leg portion inserted into the slot different from the predetermined slot,

the W-phase lead wire has: a first W-phase lead wire (first W-phase lead wire 51W) connected to the front end portion of the seventh leg portion and the front end portion of the eighth leg portion, the first W-phase lead wire being inserted into a predetermined slot different from the U-phase lead wire and the V-phase lead wire; and a second W-phase lead wire (second W-phase lead wire 52W) connected to the distal end portion of the seventh leg portion and the distal end portion of the eighth leg portion, which are inserted into the slot different from the predetermined slot.

According to (3), the coils of the U-phase, V-phase, and W-phase are electrically connected to the U-phase lead wire, V-phase lead wire, and W-phase lead wire, respectively, and the lead wires of the phases have: a first lead wire connected to the front end portions of the seventh leg portion and the eighth leg portion inserted into the predetermined slot; and a second lead wire connected to the tip ends of the seventh leg portion and the eighth leg portion, which are inserted into a slot different from the predetermined slot. Thus, the lead wires of each phase can be connected to the windings of the coils of each phase in four parallel by the two lead wires of the first lead wire and the second lead wire, and thus the number of parallel windings of the coils of each phase can be increased from two to four without increasing the number of lead wires of each phase.

(4) The stator of a rotating electrical machine according to any one of (1) to (3), wherein,

the coil has:

a first joint (first joint 451) in which the front end portion of the first leg portion and the front end portion of the second leg portion, and the front end portion of the third leg portion and the front end portion of the fourth leg portion inserted into the slot offset from each other by a predetermined number of slots in the first direction or the second direction in the circumferential direction are integrally joined and conducted, and

and a second joint (second joint 452) in which the front end portion of the fifth leg portion and the front end portion of the sixth leg portion, and the front end portion of the seventh leg portion and the front end portion of the eighth leg portion inserted into the slots offset from the predetermined number of slots in the first direction or the second direction are integrally joined and conducted.

According to (4), since the coil has the first joint portion where the front end portions of the first to fourth leg portions are integrally joined and conducted and the second joint portion where the front end portions of the fifth to eighth leg portions are integrally joined and conducted, it is possible to have two joint portions with respect to the eight segment conductors inserted into the respective slots. This can increase the radial distance between the joining portions and increase the partial discharge start voltage of the coil.

(5) The stator of a rotating electrical machine according to (4), wherein,

the distal end portion of the second leg portion, the distal end portion of the third leg portion, and the distal end portion of the fourth leg portion are bent so as to be inclined inward in the radial direction,

the distal end portion of the fifth leg portion, the distal end portion of the sixth leg portion, and the distal end portion of the seventh leg portion are bent so as to be inclined radially outward.

According to (5), since the distal end portion of the second leg portion, the distal end portion of the third leg portion, and the distal end portion of the fourth leg portion are bent so as to be inclined inward in the radial direction, and the distal end portion of the fifth leg portion, the distal end portion of the sixth leg portion, and the distal end portion of the seventh leg portion are bent so as to be inclined outward in the radial direction, the radial interval between the distal end portion of the fourth leg portion and the distal end portion of the fifth leg portion, that is, the radial interval between the first joint portion and the second joint portion, becomes large. This can further increase the partial discharge start voltage of the coil.

(6) The stator of a rotating electrical machine according to any one of (1) to (5), wherein,

The U-phase coil, the V-phase coil, and the W-phase coil each have: a first bridge (first U-phase bridge 61U, first V-phase bridge 61V, first W-phase bridge 61W) having one end portion connected to and conducting with the distal end portion of the fifth leg portion and the distal end portion of the sixth leg portion inserted into the predetermined slot, and having the other end portion connected to and conducting with the distal end portion of the fifth leg portion and the distal end portion of the sixth leg portion inserted into the slot different from the predetermined slot; and a second bridge (a second U-phase bridge 62U, a second V-phase bridge 62V, and a second W-phase bridge 62W) having one end portion connected to and conducting with the tip end portion of the fifth leg portion and the tip end portion of the sixth leg portion inserted into the slot different from the first bridge, and the other end portion connected to and conducting with the tip end portion of the fifth leg portion and the tip end portion of the sixth leg portion inserted into the slot different from the slot.

According to (6), the coils of each of the U phase, V phase, and W phase each have: a first bridge having one end portion connected to and conducting with the front end portions of the fifth leg portion and the sixth leg portion inserted into a predetermined slot, and having the other end portion connected to and conducting with the front end portions of the fifth leg portion and the sixth leg portion inserted into a slot different from the predetermined slot; and a second bridge, one end of which is connected to and conducted with the tip end of the fifth leg and the tip end of the sixth leg inserted into a predetermined slot different from the first bridge, and the other end of which is connected to and conducted with the tip end of the fifth leg and the tip end of the sixth leg inserted into a slot different from the predetermined slot. Thus, the coils of each phase can form the windings of the coils of each phase in four parallel by the two bridges of the first bridge and the second bridge, and thus the number of parallel windings of the coils of each phase can be increased from two to four without increasing the number of bridges of each phase.

Claims

1. A stator of a rotating electrical machine is provided with:

the diagonal portion of the seventh leg portion and the diagonal portion of the eighth leg portion are diagonal in a circumferential direction to a side opposite to a diagonal direction of the diagonal portion of the fifth leg portion and the diagonal portion of the sixth leg portion,

the coil has a U-phase coil, a V-phase coil, and a W-phase coil,

the U-phase coil is electrically connected with the U-phase outgoing line, the V-phase coil is electrically connected with the V-phase outgoing line, the W-phase coil is electrically connected with the W-phase outgoing line,

the U-phase outgoing line has: a first U-phase lead wire connected to the distal end portion of the seventh leg portion and the distal end portion of the eighth leg portion, which are inserted into the predetermined slot; and a second U-phase lead wire connected to the distal end portion of the seventh leg portion and the distal end portion of the eighth leg portion, which are inserted into the slot different from the predetermined slot,

The V-phase lead wire has: a first V-phase lead wire connected to the front end portion of the seventh leg portion and the front end portion of the eighth leg portion, which are inserted into the predetermined slot different from the U-phase lead wire; and a second V-phase lead wire connected to the tip end portion of the seventh leg portion and the tip end portion of the eighth leg portion, which are inserted into the slot different from the predetermined slot,

the W-phase lead wire has: a first W-phase lead wire connected to the front end portion of the seventh leg portion and the front end portion of the eighth leg portion, the front end portion being inserted into the predetermined slot different from the U-phase lead wire and the V-phase lead wire; and a second W-phase lead wire connected to the distal end portion of the seventh leg portion and the distal end portion of the eighth leg portion, which are inserted into the slot different from the predetermined slot.

2. The stator of a rotary electric machine according to claim 1, wherein,

the segmented conductor has a conductor portion having a substantially rectangular cross section, and an aspect ratio expressed by a radial thickness/circumferential width of the conductor portion is 0.5 to 0.7.

3. The stator of a rotating electrical machine according to claim 1 or 2, wherein,

The coil has:

a first joint portion in which the front end portion of the first leg portion and the front end portion of the second leg portion, and the front end portion of the third leg portion and the front end portion of the fourth leg portion inserted into the slot offset from each other by a predetermined number of slots in the first direction or the second direction in the circumferential direction are integrally joined and conducted, and

and a second joint portion in which the front end portion of the fifth leg portion and the front end portion of the sixth leg portion, and the front end portion of the seventh leg portion and the front end portion of the eighth leg portion inserted into the slots offset from the predetermined number of slots in the first direction or the second direction are integrally joined and conducted.

4. The stator of a rotary electric machine according to claim 3, wherein,

5. The stator of a rotating electrical machine according to claim 1 or 2, wherein,

the U-phase coil, the V-phase coil, and the W-phase coil each have: a first bridge having one end portion connected to and conducting with the tip end portion of the fifth leg portion and the tip end portion of the sixth leg portion inserted into the predetermined slot, and having the other end portion connected to and conducting with the tip end portion of the fifth leg portion and the tip end portion of the sixth leg portion inserted into the slot different from the predetermined slot; and a second bridge having one end portion connected to and conducting with the tip end portion of the fifth leg portion and the tip end portion of the sixth leg portion inserted into the slot different from the first bridge, and having the other end portion connected to and conducting with the tip end portion of the fifth leg portion and the tip end portion of the sixth leg portion inserted into the slot different from the slot.