WO2023272728A1

WO2023272728A1 - Motor stator and motor

Info

Publication number: WO2023272728A1
Application number: PCT/CN2021/104312
Authority: WO
Inventors: 王坤; 宋志强
Original assignee: 舍弗勒技术股份两合公司; 王坤
Priority date: 2021-07-02
Filing date: 2021-07-02
Publication date: 2023-01-05
Also published as: CN117121343A

Abstract

A motor stator, which comprises a stator core (110), a winding (120) mounted within a winding slot of the stator core (110), and a busbar (130) electrically connected to the winding (120); the winding (120) comprises a plurality of line reception ends (121), and the busbar (130) comprises a plurality of conductive terminals (131) electrically connected to the line reception ends (121) and an insulating component (133) causing the plurality of conductive terminals (131) to be insulated from each other; The stator core (110) comprises at least one positioning hole (111), the busbar (130) further comprises at least one positioning post (134), and each positioning post (134) is inserted into a positioning hole (111) and assists the positioning of the busbar (130) relative to the stator core (110). Further provided is a motor comprising the motor stator.

Description

Motor stator and motor

technical field

The present application relates to the field of motors, and in particular to a motor stator and a motor including the motor stator.

Background technique

The hairpin permanent magnet synchronous motor (hairpin PMSM) has a high filling rate, and thus has been widely used in the field of electric vehicles.

For non-hairpin motors, the connection between its copper wire (winding) and the high-voltage cable (HV-cable) of the power module (inverter) is simple, and the copper wire assembled in the stator is pressed into the copper terminal (cable lug) , and then connect the copper terminal with the high voltage cable by means of bolts, rivets or welding. This connection method is reliable because the copper wire is soft and the connection has good toughness, which can withstand vibration and acceleration well.

But for hairpin motors, the connection method is completely different. Instead of using copper wires, the stator windings use copper strips (or copper conductors). The copper strip is bent directly on the production line, and then the shape of the copper strip is fixed, and the shape of the copper strip cannot be changed arbitrarily, otherwise it will easily cause damage to the copper strip.

One possible solution currently available for connecting copper strips and high voltage cables is welding. Figures 1 and 2 show a possible busbar connection scheme for a hairpin motor.

As shown in FIGS. 1 and 2 , the stator 100 includes a stator core 110 and a winding 120 . Winding 120 is a hairpin winding formed from a flat copper strip having a generally rectangular cross-section. The copper bars of each phase winding are connected to the bus bar 130 by welding. FIG. 1 and FIG. 2 show multiple terminals (or referred to as wire terminals) 121 of the winding 120 and multiple welding points 140 of the bus bar 130 .

The bus bar 130 may include a plurality of conductive terminals 131 (or called copper plates, copper terminals), and one end of each conductive terminal 131 has a copper nut 132 for conducting the current generated in the winding 120 to the power module, or from The battery supplies current to the winding 120 .

An insulating material such as plastic is provided between at least the plurality of conductive terminals 131 to fix the shape and position of the conductive terminals 131 and to achieve insulation among the plurality of conductive terminals 131 .

The above scheme has the following problems.

The bus bar including plastic material forms a cantilever, and the joint (welding point) between the terminal 121 of the stator and the conductive terminal 131 is a rigid connection, and all the weight must be borne by this rigid connection. Under conditions of acceleration and vibration, for example during transport of the stator core or the motor and during use of the motor, the stress at the joint location is rather high and prone to fracture.

Contents of the invention

The purpose of the present application is to overcome or at least alleviate the shortcomings of the above-mentioned prior art, and provide a motor stator and a motor including the motor stator.

A motor stator is provided, which includes a stator core, a winding installed in a wire slot of the stator core, and a bus bar electrically connected to the winding,

Wherein, the winding includes a plurality of terminals, the bus bar includes a plurality of conductive terminals electrically connected to the plurality of terminals and an insulating member for insulating the plurality of conductive terminals from each other,

Wherein, the stator core includes at least one positioning hole, and the bus bar further includes at least one positioning post, and the positioning post is inserted into the positioning hole to assist the positioning of the bus bar relative to the stator core.

In at least one embodiment, the winding is a hairpin winding, and the hairpin winding includes a strip wire with a rectangular or rounded rectangular cross section.

In at least one embodiment, the terminal is connected to the conductive terminal by welding.

In at least one embodiment, the outer periphery of the positioning post has a flexible positioning portion that is interference-fitted into the positioning hole.

In at least one embodiment, the flexible positioning portion includes at least one of a plurality of raised lines, a plurality of annular ridges, and a plurality of helical ridges.

In at least one embodiment, the flexible positioning portion includes a plurality of barbs.

In at least one embodiment, the barb is formed as an annular barb or a helical barb extending continuously or discontinuously along the circumferential direction of the positioning column.

In at least one embodiment, the positioning post is integrally formed of insulating material with the insulating member.

In at least one embodiment, the stator core is formed by stacking a plurality of laminations.

In at least one embodiment, the positioning hole is a threaded hole.

In at least one embodiment, the stator core includes a plurality of positioning holes arranged along the circumferential direction of the stator core and extending along the axial direction of the stator core, the confluence A row includes a plurality of said positioning posts, and said positioning posts are interference-fitted with said positioning holes.

An electric machine is provided, which comprises an electric machine stator according to the present application.

Description of drawings

Figures 1 and 2 show a possible busbar connection scheme for a hairpin motor.

Fig. 3A shows a schematic structural diagram of a bus bar of a motor stator according to an embodiment of the present application.

FIG. 3B shows a partially enlarged view of the bus bar in FIG. 3A.

Fig. 4 shows a schematic structural diagram of a stator core and windings of a motor stator according to an embodiment of the present application.

Explanation of reference signs

100 Stator

110 stator core

111 positioning hole

120 windings

121 terminal

130 busbar

131 Conductive terminal

1311 welding column

132 brass nut

133 insulating member

134 positioning post

1341 Ring Barb

140 welding points

A axis

C Circumferential

R Radial

detailed description

Exemplary embodiments of the present application are described below with reference to the accompanying drawings.

As shown in FIGS. 3A to 4 , an embodiment of the present application provides a motor stator 100 , which includes a stator core 110 , a winding 120 installed in the slot of the stator core 110 , and a bus that is electrically connected to the winding 120 Row (busbar) 130 . The bus bar 130 may be used to conduct current generated in the winding 120 to a power module, or to supply current to the winding 120 from a battery. Therefore, the electric machine including the above-mentioned electric machine stator can be used as a generator, or can be used as a motor, or can be used as both a generator and a motor. The motor can be, but not limited to, applied to electric vehicles including pure electric vehicles and hybrid vehicles.

The winding 120 may include a plurality of terminals 121, and the bus bar 130 may include a plurality of conductive terminals 131 electrically connected to the plurality of terminals 121 and an insulating member 133 insulating the plurality of conductive terminals 131 from each other. Optionally, multiple (for example, three) conductive terminals 131 can be integrally formed with the insulating member 133 by means of injection molding or injection. In the case of injection molding or injection, optionally, other parts of the conductive terminal 131 except the two ends (the end where the copper nut 132 is located and the other end where the welding post 1311 is located) can be covered with plastic to Provide proper insulation. In another possible solution, the insulating member 133 may include a plurality of separate elements, and the plurality of elements and the plurality of conductive terminals 131 may be connected together by screws or the like. The insulating member may be made of or include plastic.

The stator core 110 may include at least one positioning hole 111 , and the bus bar 130 may further include at least one positioning post 134 , and the positioning post 134 is inserted into the positioning hole 111 to assist the positioning of the bus bar 130 relative to the stator core 110 . The "auxiliary positioning of the bus bar 130 relative to the stator core 110" here may mean that the positioning post 134 is inserted into the positioning hole 111 to help the positioning of the bus bar 130 relative to the stator core 110, but the bus bar 130 is relatively positioned relative to the stator core 110. The positioning of the iron core 110 does not necessarily depend entirely on the matching positioning of the positioning post 134 and the positioning hole 111 .

Preferably, the positioning of the positioning post 134 and the positioning hole 111 makes the bus bar 130 not significantly shift or shake relative to the stator core 110 (as described later, for vibration reduction and other purposes, the positioning post 134 can be relatively slight displacement or shaking in the positioning hole 111), even during transportation or use of the stator core 110 or the motor including the stator core.

The present application is particularly applicable to the case where the winding 120 is a hairpin winding, and the hairpin winding may include a strip-shaped wire with a rectangular or rounded rectangular cross section. The strip wire can in particular be a copper wire. The hairpin winding or its terminal has high hardness, is not easy to deform, and its position is relatively fixed. The "positioning column 134 is inserted into the positioning hole 111 to assist the positioning of the bus bar 130 relative to the stator core 110" of this application, so that the bus bar The position of 130 relative to the winding 120 of the stator 100 and its terminal 121 is fixed, so the connection between the conductive terminal 131 of the bus bar 130 and the terminal 121 is not prone to failure. The reliability and durability of the motor stator 100 and the motor can be improved.

Of course, the application is not limited to hairpin windings or hairpin motors, and the application can also be applied to other forms of windings such as round copper conductors and motor stators and motors including the windings.

Optionally, the terminal 121 is connected to the conductive terminal 131 by welding. Here, the welding post 1311 of the conductive terminal 131 can be welded to the terminal 121, here, especially, but not limited to, pressure welding can be used. The welding process is simple, and after applying the application, the welding points are not easy to break. Of course, the application scenario of the present application is not limited thereto. For example, the connection terminal 121 and the conductive terminal 131 may also be electrically connected by other methods such as riveting.

Preferably, the outer periphery of the positioning column 134 has at least one of a plurality of convex lines, a plurality of annular ridges, and a plurality of helical ridges.

Preferably, the outer periphery of the positioning post 134 has a plurality of barbs.

Preferably, the barb is formed as an annular barb 1341 (as shown in FIG. 3B ) or a helical barb extending continuously or intermittently along the circumference of the positioning post 134 .

These structures facilitate the positioning of the positioning post 134 in the positioning hole 111 , so that the positioning post 134 can be easily inserted into the positioning hole 111 , and reliably prevent the positioning post 134 from coming out of the positioning hole 111 . The arrangement of the above-mentioned convex strips, annular ridges, spiral ridges or barbs makes the positioning post 134 easy to be positioned in the positioning hole 111, and makes this positioning have a certain degree of flexibility, that is, in the convex strips, annular ridges, spiral When the ridge or barb is deformed by force, the positioning column 134 can move a small amount relative to the positioning hole 111, which can play a role in damping vibration and is beneficial to prevent the breakage of the welding point. These ridges, annular ridges, helical ridges or barbs or combinations thereof may constitute flexible detents on the detent posts 134 .

Preferably, the positioning post 134 is integrally formed of an insulating material including plastic with the insulating member 133 . For example, the positioning post 134 is formed at the same time when the insulating member 133 is injection-molded or injection-formed or (the insulating member in) the bus bar 130 is injection-molded or injection-formed. In this way, the forming method of the positioning column is simple, and the cost of the bus bar 130 is low. Also advantageous are the aforementioned ridges or ridges or barb formations that form the positioning posts. It is understood that the present application is not limited to the fact that the positioning post is formed entirely of insulating material. For example, the positioning post may also include a metal skeleton.

Optionally, the stator core 110 may be formed by stacking a plurality of laminations. The plurality of laminations may be, for example, silicon steel sheets. A plurality of laminations of the stator core 110 can be connected together with, for example, rivets, and the plurality of laminations can be compressed, or there are some small gaps between the plurality of laminations, and these gaps can be used to position the positioning posts 134. The ridges or ridges or barbs of the locating post 134 can improve the connection strength between the locating post 134 and the locating hole 111 .

Optionally, the positioning hole 111 may also be a threaded hole. Regardless of whether the stator core 110 is formed by stacking a plurality of laminations, or whether there are some small gaps between the laminations, the positioning hole 111 can be formed as a threaded hole. For example, threaded holes may be drilled in the stator core 110 .

Of course, the present application is not limited thereto, and the positioning hole 111 can also be a hole with a plurality of continuous or discontinuous annular grooves, which is also conducive to the positioning of the positioning post 134. Of course, the present application can also be applied to the situation where the positioning hole 111 is a light hole. For example, in the case where the stator core 110 is formed by stacking a plurality of laminations, although a threaded hole is not intentionally formed but a light hole is formed, the light hole The inner surface of the can still have a certain roughness to facilitate the positioning of the positioning post 134 .

It can be understood that the positioning post 134 preferably has an interference fit with the positioning hole 111 . In the case where the stator core 110 is formed from a plurality of laminations, the positioning holes 111 (or, to be precise, the portion where the positioning holes 111 are located on each lamination) may be pressed or punched out during the process of pressing or stamping the laminations. ), the inner diameter of these positioning holes 111 can be smaller than the outer diameter of the positioning post 134 on the bus bar 130 (especially the outer diameter of the raised strip or ridge or barb), and these positioning holes 111 can be blind holes or through holes. hole.

The stator core 110 preferably includes a plurality of positioning holes 111 arranged along the circumferential direction C of the stator core 110 and extending along the axial direction A of the stator core 110 . The bus bar 130 may include a plurality of positioning posts 134 , and the positioning posts 134 may also extend along the axis A. As shown in FIG. The figure shows five positioning posts 134 and five positioning holes 111, but the number of positioning posts 134 and positioning holes 111 is not limited thereto. The positioning hole 111 may be formed on the outer side in the radial direction R of the winding 120 . Of course, the present application is not limited thereto. For example, in the case of an external rotor motor, the slots on the stator core are usually formed on the outer periphery of the stator core. A positioning hole is formed inward on R.

Here, the present application also provides a motor, which includes the above motor stator. The motor can be an inner rotor motor or an outer rotor motor.

In at least one embodiment of the present application, the weight of the bus bar 130 and its surroundings is not only borne by the welding points, but also borne by the positioning post 134 , especially the positioning post 134 having a barb structure.

In at least one embodiment of the present application, a rigid + flexible joint is provided, especially the connection joint between the positioning post 134 with a barb structure and the positioning hole 111 formed of an insulating material such as plastic, which has a good Anti-vibration performance. Since the plastic barb structure is a kind of flexible joint, it can play a role of damping in vibration compared with rigid joints, which can reduce the risk of fracture of welding points.

In this application, the bus bar 130 no longer forms a cantilever beam, and the stress distribution is optimized, especially in the case of having multiple positioning posts 134 and multiple positioning holes 111 .

Of course, the present application is not limited to the above-mentioned embodiments, and those skilled in the art can make various modifications to the above-mentioned embodiments of the present application under the teaching of the present application without departing from the scope of the present application.

Claims

A motor stator, comprising a stator core (110), a winding (120) installed in a wire slot of the stator core (110), and a bus bar (130) electrically connected to the winding (120),

Wherein, the winding (120) includes a plurality of terminals (121), and the bus bar (130) includes a plurality of conductive terminals (131) electrically connected to the plurality of terminals (121) and makes the plurality of terminals (121) an insulating member (133) that insulates the conductive terminals (131) from each other,

Wherein, the stator core (110) includes at least one positioning hole (111), the bus bar (130) also includes at least one positioning post (134), and the positioning post (134) is inserted into the positioning hole (111 ) to assist the positioning of the busbar (130) relative to the stator core (110).
The motor stator according to claim 1, wherein the winding (120) is a hairpin winding, and the hairpin winding includes a strip-shaped wire with a cross-section of a rectangle or a rectangle with rounded corners.
The motor stator according to claim 1, wherein the connection terminal (121) and the conductive terminal (131) are connected by welding.
The motor stator according to claim 1, wherein the outer periphery of the positioning column (134) has a flexible positioning portion which is interference-fitted in the positioning hole (111).
The motor stator according to claim 4, wherein the flexible positioning portion comprises at least one of a plurality of convex lines, a plurality of annular ridges, and a plurality of helical ridges.
The electric machine stator of claim 4, wherein the flexible positioning portion comprises a plurality of barbs.
The motor stator according to claim 6, wherein the barb is formed as an annular barb or a helical barb continuously or discontinuously extending along the circumferential direction of the positioning post (134).
The motor stator according to claim 1, wherein the positioning post (134) is integrally formed of an insulating material with the insulating member (133).
The motor stator according to claim 1, wherein the stator core (110) is formed by stacking a plurality of laminations.
The motor stator according to claim 1, wherein the positioning hole (111) is a threaded hole.
The motor stator according to claim 1, wherein, the stator core (110) includes the stator core (110) arranged along the circumferential direction (C) of the stator core (110), and along the stator core Axial

(A) a plurality of positioning holes (111) extending, the busbar (130) includes a plurality of positioning posts (134), and the positioning posts (134) interfere with the positioning holes (111) Cooperate.
A motor comprising the motor stator according to any one of claims 1 to 11.