CN111525720A

CN111525720A - Stator winding, stator with same, motor and vehicle

Info

Publication number: CN111525720A
Application number: CN202010383049.5A
Authority: CN
Inventors: 贾广隆; 胡明; 陈致初; 李伟业; 胡勇峰; 郑钦; 史俊旭; 何明杰; 胡华; 石鸿佼; 叶文宏; 王彦霖
Original assignee: CRRC Zhuzhou Institute Co Ltd
Current assignee: CRRC Zhuzhou Institute Co Ltd
Priority date: 2020-05-08
Filing date: 2020-05-08
Publication date: 2020-08-11
Anticipated expiration: 2040-05-08
Also published as: CN111525720B

Abstract

The invention discloses a stator winding, a stator, a motor and a vehicle, wherein the stator winding comprises a multi-phase winding, each phase winding comprises a plurality of groups of parallel winding branches, each group of winding branches comprises two parallel branches, and each branch comprises a plurality of coils which are sequentially arranged on a circumferential iron core slot of a stator iron core and are mutually connected in series; in two parallel branches in each group of winding branches, one branch comprises m coils with the pitch of y and n coils with the pitch of y +2, the other branch comprises m coils with the pitch of y +2 and n coils with the pitch of y, the m coils with the pitch of y are concentrically arranged at the inner sides of the m coils with the pitch of y +2 in the other branch in a one-to-one correspondence manner, the n coils with the pitch of y are concentrically arranged at the inner sides of the n coils with the pitch of y +2 in the other branch in a one-to-one correspondence manner, wherein m and n are equal and are positive integers more than or equal to 1. The invention has the advantages of ensuring the symmetry of each branch, simple and compact structure, simple assembly, small motor volume and the like.

Description

Stator winding, stator with same, motor and vehicle

Technical Field

The invention mainly relates to the technical field of motors, in particular to a stator winding, a stator with the stator winding, a motor and a vehicle.

Background

With the rapid development of new energy automobile technology, the performance requirement of a driving motor as one of the key execution components of an electric automobile is higher and higher. At present, high speed, light weight and high efficiency become the development trend of driving motors, and have higher requirements on the power density, the high efficiency area and the heat dissipation capacity of the motors.

The stator winding can be divided into round wires and flat wires, and compared with the round wire winding, the flat wire winding can effectively improve the slot filling rate of the motor, reduce the copper consumption of the motor so as to improve the efficiency of the motor, and simultaneously can also reduce the height of the end part of the motor winding so as to reduce the volume of the motor and improve the power/torque density. However, the flat wire winding has an inherent skin effect phenomenon, and particularly, the skin effect is obvious in a high-speed motor. To reduce the skin effect, the number of layers of the conductor in the stator slot is generally increased, such as 4 layers, 6 layers, 8 layers, and the like. Because the conductors of each parallel branch are distributed at different positions of the inner diameter of the stator slot, if each branch is asymmetric, the back electromotive force, the resistance and the inductance are greatly different, so that a circulating current is formed, the additional loss is increased, the efficiency is reduced, the local over-temperature of a motor winding is caused, and the service life of the motor is shortened.

The winding arrangement and connection mode of a flat wire motor is one of the difficulties in the design of the motor, and the existing coil arrangement mode generally has the following problems:

1) the outgoing line of the winding of the conventional flat wire motor, the neutral point connection and the like need a bus bar with a complex structure, and the height of the bus bar is higher than that of the end part of the winding, so that the axial length of the motor is increased;

2) the existence of more different-sex coils increases the difficulty of coil manufacture and is not beneficial to batch production;

3) the problem of asymmetric winding branches exists, so that differences of counter electromotive force, resistance, inductance and the like exist, the performance of the motor is reduced, winding circulation is caused, additional loss of the motor is increased, and local overheating of the motor is caused.

Disclosure of Invention

The technical problem to be solved by the invention is as follows: aiming at the technical problems in the prior art, the invention provides a stator winding with symmetrical branches, a stator, a motor and a vehicle.

In order to solve the technical problems, the technical scheme provided by the invention is as follows:

a stator winding comprises multiphase phase windings, each phase winding comprises a plurality of groups of parallel winding branches, each group of winding branches comprises two parallel branches, and each branch comprises a plurality of coils which are sequentially arranged on a circumferential iron core slot of a stator iron core and are mutually connected in series; in two parallel branches in each group of winding branches, one branch comprises m coils with the pitch of y and n coils with the pitch of y +2, the other branch comprises m coils with the pitch of y +2 and n coils with the pitch of y, the m coils with the pitch of y are concentrically arranged at the inner sides of the m coils with the pitch of y +2 in the other branch in a one-to-one correspondence manner, the n coils with the pitch of y are concentrically arranged at the inner sides of the n coils with the pitch of y +2 in the other branch in a one-to-one correspondence manner, wherein m and n are equal and are positive integers more than or equal to 1.

As a further improvement of the above technical solution:

the coil located at the innermost layer and the outermost layer of the iron core groove comprises a first coil main body and a first bending portion, the first coil main body comprises two first supporting rods arranged in parallel and a first head portion connected with one ends of the two first supporting rods, the first bending portion is located at the other ends of the two first supporting rods and forms a welding end, the first bending portion faces one side of the width direction of the first coil main body, and the bending direction of the first bending portion located at the innermost layer of the iron core groove is opposite to that of the first bending portion located at the outermost layer of the iron core groove.

The first head part is V-shaped or arc-shaped.

The coil that is located the iron core groove intermediate level all includes second coil main part and second kink, second coil main part includes two second branch of mutual parallel arrangement and the second head of connecting two second branch one ends, the second kink is located the other end of two second branches and forms the welding end, and the second kink on two second branches all follows the width direction of second coil main part just keeps away from each other.

The second head is V-shaped or arc-shaped.

The neutral points of the coils are connected through copper busbars, and the height of the copper busbars is not more than that of welding ends of the coils.

The two parallel branches are connected end to end.

The phase winding comprises a group of winding branches, wherein one branch of the winding branches comprises coils A1-a2, A3-a4, A5-a6 and A7-A8, and the other branch of the winding branches comprises coils B1-B2, B3-B4, B5-B6 and B7-B8;

the upper layer side and the lower layer side of the coils A1-a2 and B1-B2 are positioned at the 1 st layer (namely the innermost layer) of the groove bottom in the iron core groove along the direction of the groove opening, the pitch of A1-a2 is y, and the pitch of B1-B2 is y + 2;

the pitch of A3-a4 is y, the pitch of B3-B4 is y +2, the upper layer side of the A3-a4 is positioned at the 2 nd layer of the iron core groove, and the lower layer side of the A3-a4 is positioned at the 3 rd layer of the iron core groove;

the pitch of A5-a6 is y +2, the pitch of B5-B6 is y, the upper layer edge of the A5-a6 is positioned at the 4 th layer of the iron core groove, and the lower layer edge of the A5-a6 is positioned at the 5 th layer of the iron core groove;

the pitch of A7-A8 is y +2, the pitch of B7-B8 is y, and the upper layer side and the lower layer side of the A7-A8 are both positioned at the 6 th layer (namely the outermost layer) of the iron core slot;

a1-a2 was connected to A3-a4 at the weld end, A3-a4 coil was connected to A5-a6 at the weld end, A5-a6 was connected to A7-A8 at the weld end, and so on;

the coil connection sequence is from the 1 st layer to the 6 th layer, and then from the 6 th layer to the 1 st layer, and the cycle is repeated.

A stator comprises a stator core and the stator winding, wherein the stator core is provided with a plurality of core slots in the circumferential direction, and phase windings in the stator winding are arranged in the core slots.

An electric machine comprises the stator.

A vehicle comprises the motor.

Compared with the prior art, the invention has the advantages that:

according to the stator winding, the stator, the motor and the vehicle, two parallel branches of each winding branch respectively comprise m coils with the pitch of y, n coils with the pitch of y +2, m coils with the pitch of y +2 and n coils with the pitch of y, the coils with the pitch of y +2 are concentrically arranged in a one-to-one correspondence mode, transposition is carried out through the coils with different pitches, phase differences among different branches are eliminated, each branch is guaranteed to be completely symmetrical, and therefore the performance of the motor is improved.

According to the stator winding, the stator, the motor and the vehicle, the shape of each coil is uniform U-shaped, and the opposite coil and the cross-connection coil are eliminated, so that the stator winding, the stator, the motor and the vehicle are convenient to assemble and produce in batches.

According to the stator winding, the stator, the motor and the vehicle, the neutral points of the coils are welded through the single copper busbar, the height of the neutral points is not more than that of the welding ends of the coils, the structure is simple, and the height of the end part of the winding is reduced, so that the size of the motor is reduced.

Drawings

Fig. 1 is a schematic structural diagram of a stator winding according to an embodiment of the present invention.

Fig. 2 is a schematic layout diagram of a U-phase winding according to an embodiment of the present invention.

Fig. 3 is a schematic structural diagram of a first layer coil in the present invention.

Fig. 4 is a schematic structural diagram of a second-layer coil and a third-layer coil in an embodiment of the invention.

Fig. 5 is a schematic structural diagram of a fourth layer coil and a fifth layer coil in an embodiment of the invention.

Fig. 6 is a schematic structural diagram of a sixth layer coil according to an embodiment of the present invention.

The reference numbers in the figures denote: 11. a first coil body; 111. a first support bar; 112. a first head portion; 12. a first bent portion; 21. a second coil body; 211. a second support bar; 212. a second head; 22. a second bent portion; 3. copper busbar; 4. a stator core is provided.

Detailed Description

The invention is further described below with reference to the figures and the specific embodiments of the description.

As shown in fig. 1 to 6, the stator winding of the present embodiment includes a multi-phase winding, each phase winding includes a plurality of groups of winding branches connected in parallel, each group of winding branches includes two branches connected in parallel, and each branch includes a plurality of coils sequentially arranged in a circumferential core slot of a stator core 4 and connected in series with each other; in two parallel branches in each group of winding branches, one branch comprises m coils with the pitch of y and n coils with the pitch of y +2, the other branch comprises m coils with the pitch of y +2 and n coils with the pitch of y, the m coils with the pitch of y are concentrically arranged at the inner sides of the m coils with the pitch of y +2 in the other branch in a one-to-one correspondence manner, the n coils with the pitch of y are concentrically arranged at the inner sides of the n coils with the pitch of y +2 in the other branch in a one-to-one correspondence manner, wherein m and n are equal and are positive integers more than or equal to 1.

The stator winding respectively comprises m coils with the pitch of y, n coils with the pitch of y +2, m coils with the pitch of y +2 and n coils with the pitch of y in two parallel branches of each winding branch, the coils with the pitch of y +2 and the coils with the pitch of n y are concentrically arranged in a one-to-one correspondence mode, the phase difference between different branches is eliminated through transposition of the coils with different pitches, each branch is guaranteed to be completely symmetrical, and therefore the performance of a motor is improved.

As shown in fig. 3 and 6, in the present embodiment, each of the coils located at the innermost layer (i.e., the first layer in the direction from the slot bottom to the slot opening) and the outermost layer (i.e., the last layer in the direction from the slot bottom to the slot opening) of the core slot includes a first coil main body 11 and a first bent portion 12, the first coil main body 11 includes two first legs 111 arranged in parallel with each other and a first head 112 connecting one ends of the two first legs 111, the first bent portion 12 is located at the other end of the two first legs 111 and forms a welded end, the first bent portion 12 is bent toward one side of the first coil main body 11 in the width direction, and the first bent portion 12 located at the innermost layer of the core slot is bent in the opposite direction (toward the right side and the left side, respectively) to the first bent portion 12 located at the outermost layer of the core slot.

Preferably, the first head 112 has a V-shape or an arc shape.

As shown in fig. 4 and 5, in the present embodiment, each of the coils located in the middle layer of the core slot includes a second coil main body 21 and a second bending portion 22, the second coil main body 21 includes two second struts 211 arranged in parallel with each other and a second head portion 212 connected to one ends of the two second struts 211, the second bending portion 22 is located at the other ends of the two second struts 211 and forms a welding end, and the second bending portions 22 on the two second struts 211 are both located along the width direction of the second coil main body 21 and are far away from each other.

Preferably, the second head 212 has a V-shape or an arc shape.

Because each coil adopts the U type or the V type, the opposite coil and the crossover coil are cancelled, thereby being convenient for assembly and batch production.

In this embodiment, the neutral points (e.g., a48 and b48 in fig. 2) of the coils are connected through the copper busbar 3, and the height of the copper busbar 3 does not exceed the height of the welding end of the coil, so that the structure is simple, and the height of the winding end part is reduced, thereby reducing the volume of the motor.

In this embodiment, the phase winding comprises a set of winding branches, one of which comprises coils a1-a2, A3-a4, a5-a6 and a7-A8, and the other comprises coils B1-B2, B3-B4, B5-B6 and B7-B8;

the upper layer side and the lower layer side of the coils A1-a2 and B1-B2 are positioned on the 1 st layer of the inner groove bottom of the iron core groove along the direction of the groove opening, the pitch of A1-a2 is y, and the pitch of B1-B2 is y + 2;

the pitch of A7-A8 is y +2, the pitch of B7-B8 is y, and the upper layer side and the lower layer side of the A7-A8 are both positioned at the 6 th layer of the iron core slot;

Specifically, taking a motor with a 48-slot and 8-pole branch number of 2 as an example, the number of coil layers sequentially increases from the slot bottom to the slot opening, i.e., from the first layer to the sixth layer (in other embodiments, two, four, eight or more layers may also be provided), and the wiring diagram of the U-phase winding is shown in fig. 2;

branch 1: a-a, arm 2: B-B, A1-a2, A3-a4, A5-a6 and the like form a U-shaped coil. A1-a2 and B1-B2 together form a concentric U-shaped coil, the shape of which is shown in FIG. 3. The pitch of A1-a2 was 5 and the pitch of B1-B2 was 7. The upper and lower edges of the A1-a2 coil of branch 1 are located at the first layer, the upper edge of A3-a4 is located at the 2 nd layer, and the lower edge is located at the 3 rd layer, as shown in FIG. 4; the upper layer side of the A5-a6 coil is positioned at the 4 th layer, and the lower layer side is positioned at the 5 th layer, as shown in FIG. 5; the upper and lower edges of the a7-A8 coil are at layer 6, as shown in fig. 6. The upper layer side and the lower layer side of the B1-B2 coil of the branch 2 are positioned on the first layer, the upper layer side of the B3-B4 is positioned on the 2 nd layer, and the lower layer side is positioned on the 3 rd layer; the upper layer edge of the B5-B6 coil is positioned at the 4 th layer, and the lower layer edge is positioned at the 5 th layer; the upper and lower edges of the B7-B8 coil were located at layer 6. The A1-a2 coil was connected to the A3-a4 coil at the weld end, the A3-a4 coil was connected to the A5-a6 coil at the weld end, the A5-a6 coil was connected to the A7-A8 coil at the weld end, and so on. The coil connection sequence is from layer 1 to layer 6 and then from layer 6 to layer 1, and the process is repeated.

In other embodiments, of course, the coil arrangement mode may also be kept unchanged, and two parallel branches in the above embodiments are connected end to end, that is, each group of winding branches includes one branch, so that complete symmetry of each branch can also be realized; or each parallel branch can be regarded as being formed by connecting two branches in series, that is, each group of winding branches comprises four branches or more, and complete symmetry of each branch can also be realized.

The invention also discloses a stator which comprises the stator core 4 and the stator winding, wherein the stator core 4 is provided with a plurality of core slots in the circumferential direction, and the phase windings in the stator winding are arranged in the core slots. The stator of the invention comprises a stator winding as described above, with the same advantages as described above for the stator winding.

The invention further discloses an electric machine comprising a stator as described above. The motor of the invention also comprises the stator winding, has the advantages of the stator winding, and has simple integral structure, small volume and high working stability.

The invention further discloses a vehicle comprising an electric machine as described above. The vehicle of the invention comprises a stator winding as described above, with the same advantages as described above for the stator winding.

The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above-mentioned embodiments, and all technical solutions belonging to the idea of the present invention belong to the protection scope of the present invention. It should be noted that modifications and embellishments within the scope of the invention may be made by those skilled in the art without departing from the principle of the invention.

Claims

1. A stator winding comprises a multiphase phase winding and is characterized in that each phase winding comprises a plurality of groups of parallel winding branches, each group of winding branches comprises two parallel branches, and each branch comprises a plurality of coils which are sequentially arranged on a circumferential iron core slot of a stator iron core (4) and are mutually connected in series; in two parallel branches in each group of winding branches, one branch comprises m coils with the pitch of y and n coils with the pitch of y +2, the other branch comprises m coils with the pitch of y +2 and n coils with the pitch of y, the m coils with the pitch of y are concentrically arranged at the inner sides of the m coils with the pitch of y +2 in the other branch in a one-to-one correspondence manner, the n coils with the pitch of y are concentrically arranged at the inner sides of the n coils with the pitch of y +2 in the other branch in a one-to-one correspondence manner, wherein m and n are equal and are positive integers more than or equal to 1.

2. A stator winding according to claim 1, wherein the coils at the innermost layer and the outermost layer of the core slot each comprise a first coil body (11) and a first bent portion (12), the first coil body (11) comprises two first support bars (111) arranged in parallel with each other and a first head portion (112) connecting one ends of the two first support bars (111), the first bent portion (12) is located at the other end of the two first support bars (111) and forms a welded end, the first bent portion (12) is bent toward one side of the width direction of the first coil body (11), and the first bent portion (12) at the innermost layer of the core slot is bent in the opposite direction to the first bent portion (12) at the outermost layer of the core slot.

3. A stator winding according to claim 2, characterized in that the first head (112) is V-shaped or arc-shaped.

4. A stator winding according to any one of claims 1 to 3, wherein the coils in the middle layer of the core slots each comprise a second coil body (21) and a second bent portion (22), the second coil body (21) comprises two second struts (211) arranged in parallel with each other and a second head portion (212) connecting one ends of the two second struts (211), the second bent portion (22) is located at the other ends of the two second struts (211) and forms a welded end, and the second bent portions (22) on the two second struts (211) are both located along the width direction of the second coil body (21) and are far away from each other.

5. A stator winding according to claim 4, characterized in that the second head (212) is V-shaped or arc-shaped.

6. A stator winding according to claim 4, wherein the neutral points of the coils are connected through a copper busbar (3), and the height of the copper busbar (3) does not exceed the height of the welding end of the coil.

7. A stator winding according to any one of claims 1 to 3, wherein the two parallel branches are connected end to end.

8. A stator winding according to any one of claims 1 to 3, wherein the phase winding comprises a set of winding branches, one of the winding branches comprises coils A1-a2, A3-a4, A5-a6 and A7-A8, and the other branch comprises coils B1-B2, B3-B4, B5-B6 and B7-B8;

9. A stator, characterized by comprising a stator core (4) and a stator winding according to any one of claims 1 to 8, the stator core (4) being provided with a plurality of core slots in a circumferential direction, phase windings of the stator winding being arranged in the core slots.

10. An electrical machine comprising a stator according to claim 9.

11. A vehicle characterized by comprising the motor according to claim 10.