CN118137693A - Stator assembly and motor comprising same - Google Patents

Abstract

The invention relates to a stator assembly and an electric machine comprising the stator assembly, wherein the stator assembly comprises: the stator core is provided with a plurality of tooth grooves arranged on the inner side in the radial direction, the stator winding is composed of a plurality of conductor elements, a part of the conductor elements are positioned in the tooth grooves, the conductor elements in each tooth groove in the plurality of tooth grooves are sequentially arranged into a plurality of layers in the radial direction, for each branch of each phase winding, the part of the branch of the phase winding in each 8 tooth grooves from an access point is defined as a winding period, in the same winding period, conductors in different tooth grooves are positioned in two layers with adjacent layer numbers, and the layer numbers of the layers where the conductors in the adjacent two tooth grooves are positioned are different. The invention can effectively improve the slot filling rate of the motor, uses fewer types of conductor elements, is convenient for automatic wire-down, and can save the axial space of the winding end when the welding end and the wire outlet end are arranged at one side.

Description

Stator assembly and motor comprising same

Technical Field

The invention relates to the technical field of motors, in particular to a stator assembly and a motor comprising the stator assembly.

Background

The main components of the motor include a stator assembly and a rotor assembly. For electric machines that do not use permanent magnets, the stator assembly includes a stator core and stator windings, and the rotor assembly includes a rotor and rotor windings. The stator winding is mounted on the stator core, and when a current is passed through the stator winding, a magnetic field is generated in the stator core. The magnetic field interacts with the rotor assembly to rotate the rotor, converting electrical energy into mechanical energy.

The conductors used for the stator windings may be selected from metal conductors having a circular cross-section or metal conductors having a rectangular cross-section. An electric motor employing a metal conductor having a rectangular cross section is also called a flat wire electric motor. Compared with a metal conductor with a circular cross section, when the metal conductor with a rectangular cross section is adopted, the metal conductor can be more regularly arranged in the tooth slot of the stator core, so that the motor has higher slot filling rate, stronger magnetic field can be generated, and the flat wire motor has better performance.

The flat wire motor is widely applied to the industrial fields of hydropower, wind power and the like. In recent years, with the development of new energy automobiles, the application of flat wire motors to electric vehicles is also increasing. In order to make the flat wire motor better adapt to the use requirement of a new energy automobile, the flat wire motor with higher performance and lower manufacturing cost needs to be provided.

Disclosure of Invention

In view of this, the present invention proposes the following technical solution.

A stator assembly, comprising:

a stator core having a plurality of slots provided at a radially inner side,

A stator winding composed of a plurality of conductor elements, a part of which is positioned in the tooth slot, and the conductor elements in each tooth slot of the plurality of tooth slots are sequentially arranged in a plurality of layers along the radial direction, the stator winding comprises a U-phase winding, a V-phase winding and a W-phase winding, the U-phase winding, the V-phase winding and the W-phase winding are formed by mutually connecting the plurality of conductor elements,

For each branch of each of the U-phase winding, the V-phase winding and the W-phase winding, the part of the branch of the phase winding in each 8 tooth slots from the access point is defined as a winding period, and in the same winding period, conductors in different tooth slots of the phase winding are positioned in two adjacent layers with different layer numbers, and the layer numbers of the layers where the conductors in the two adjacent tooth slots are positioned are different.

According to one example of the present invention, two-way parallel or four-way parallel is employed for each of the U-phase, V-phase, and W-phase windings, the absolute value of the difference in layer numbers between the conductor in the last slot in each winding cycle and the conductor in the first slot in the next winding cycle being 1 or 3.

According to one example of the invention, for each of the U-, V-and W-phase windings, a branch is taken, where there is only a conductor in the last slot of one winding cycle and a conductor in the first slot of the next winding cycle in the one winding cycle at the same layer number, and the absolute value of the difference between the conductor in the last slot of each remaining winding cycle and the layer number at which the conductor in the first slot of the next winding cycle is located is 1 or 3.

According to one example of the invention, when the absolute value of the difference between the layer number where the conductor in the last slot in each winding cycle is located and the conductor in the first slot in the next winding cycle is 1, the span of the stator winding between the two slots is 6;

When the absolute value of the difference between the layer number of the conductor in the last slot in each winding cycle and the layer number of the conductor in the first slot in the next winding cycle is 3, the span of the stator winding between the two slots is 5.

According to one example of the invention, the stator windings are equally spaced in the same winding cycle.

According to an example of the present invention, the stator winding has a crown end and a weld end, and the wire outlet end of each phase winding of the three-phase winding is located on the same side as the weld end.

According to one example of the invention, the number of slots is 48 and the number of conductor elements of the stator winding in each slot is 8.

According to one example of the invention, the conductor element comprises only U-shaped conductor elements.

According to one example of the invention, the stator winding is a short distance winding.

The invention also proposes an electric machine comprising a stator assembly as described above.

By adopting the stator assembly and the motor according to the invention, one of the following advantages can be achieved: the motor slot filling rate is effectively improved, the motor direct current resistance and the high-frequency alternating current resistance are reduced, the motor power density and the motor efficiency are improved, the lead-out terminal or the star connection terminal is relatively close to the design of the bus bar, the variety of conductor elements is reduced so as to facilitate automatic wire-off, and the welding terminal and the lead-out terminal are arranged on one side so as to save the axial space of the winding end.

Other features and advantages of the present invention will be described in the following detailed description of the invention, taken in conjunction with the accompanying drawings.

Drawings

Exemplary embodiments of the present invention are described with reference to the accompanying drawings, in which:

fig. 1 illustrates a perspective view of a stator assembly according to an embodiment of the present invention.

Fig. 2 illustrates an axial view of a stator assembly according to an embodiment of the present invention.

Fig. 3 shows a schematic view of a conductor element for forming a stator winding.

Fig. 4 shows a schematic arrangement of a plurality of conductor elements in one slot.

Fig. 5 shows a schematic of a stator three-phase winding with one branch and with a star connection.

Fig. 6 shows a schematic diagram of two parallel stator three-phase windings with star connections.

Fig. 7 shows a schematic development of a U-phase winding of two parallel three-phase windings.

Fig. 8 shows a schematic development of a V-phase winding of two parallel three-phase windings.

Fig. 9 shows an expanded schematic of a W-phase winding of two parallel three-phase windings.

Fig. 10 shows an expanded schematic of two parallel three-phase windings.

All the figures are schematic and not necessarily to scale, and they show only those parts which are necessary in order to elucidate the invention, the other parts being omitted or merely mentioned. That is, the present invention may include other components in addition to those shown in the drawings.

In the drawings, identical and/or functionally identical technical features are provided with the same or similar reference signs.

Detailed Description

Embodiments of the present invention are described below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding and enabling description of the invention to one skilled in the art. It will be apparent, however, to one skilled in the art that the present invention may be practiced without some of these specific details. Furthermore, it should be understood that the invention is not limited to specific described embodiments. Rather, any combination of the features and elements described below is contemplated to implement the invention, whether or not they relate to different embodiments. Thus, the following aspects, features, embodiments and advantages are merely illustrative and should not be considered features or limitations of the claims except where explicitly set out in a claim.

Description of orientations such as "upper", "lower", "inner", "outer", "radial", "axial", etc. which may be used in the following description are for convenience of description only and are not intended to limit the inventive arrangements in any way unless explicitly stated. Furthermore, terms such as "first," "second," and the like, are used hereinafter to describe elements of the present application, and are merely used for distinguishing between the elements and not intended to limit the nature, sequence, order, or number of such elements.

Fig. 1 shows a perspective view of a stator assembly according to the present invention. As can be seen in fig. 1, the stator assembly 100 includes a stator core 110 and stator windings 120. The stator core 110 has a substantially cylindrical shape so as to house a rotor assembly, not shown, at a radially inner portion thereof. The stator core 110 includes a stator core body 1101, and a portion of the stator core body 1101 radially near an outer edge is provided with a plurality of passages 1102 extending in an axial direction, and the plurality of passages 1102 may be used for passage of a cooling fluid to cool the stator. A plurality of first grooves 1103 extending in the axial direction are provided on the outer wall of the stator core body 1101 so as to serve as welds to weld-fix the plurality of stator laminations. The first groove 1103 may also cooperate with a protrusion on the inner wall of the motor housing, not shown, to secure the stator assembly 100. Further, a second groove 1104 extending in the circumferential direction is also provided on the outer wall of the stator core body 1101 for entry of cooling oil. The cooling oil introduced into the second groove 1104 then enters the passage 1102, thereby achieving cooling of the stator.

As an alternative embodiment, the stator core 110 may be formed of a plurality of stacked silicon steel sheets.

The stator winding 120 is mounted on the stator core 110. Specifically, a portion of the stator winding 120 is accommodated in a tooth slot provided on a radially inner wall of the stator core 110. As shown in fig. 1, in the axial direction of the stator assembly 100, both ends of the stator winding 120 are located outside the stator core 110, and a portion of the stator winding 120 located between both ends is received in a tooth groove formed on a radially inner wall of the stator core 110. For convenience of description, both ends of the stator winding 120 located outside the stator core 110 in the axial direction are referred to as a first end 1201 and a second end 1202, respectively.

Fig. 2 shows an axial view of the stator core 110. As can be seen from fig. 2, the stator core 110 is provided radially inside with a plurality of stator teeth 112, and a tooth slot 113 for accommodating the stator winding 120 is formed between two adjacent stator teeth 112. Preferably, the plurality of stator teeth 112 are uniformly arranged in the circumferential direction. Accordingly, the plurality of tooth grooves 113 are also uniformly arranged in the circumferential direction. The number of the slots 113 may be set as desired. Advantageously, the number of gullets 113 is set to a multiple of 3, for example to 48, 54, 72, etc.

As a preferred embodiment of the present invention, 48 slots are shown in fig. 2 and are numbered S1, S2, S3, …, S48 in turn in a counterclockwise direction. The numbering shown in fig. 2 is for ease of description only and does not have any other particular meaning. Any other numbering scheme than that shown in fig. 2 may be used.

In each spline 113, a different number of conductors may be provided. Those skilled in the art will appreciate that a number of layers ranging from 2 to 10 may be provided.

The inventors found that for low layer schemes, such as 2 layers or 4 layers, the flat wire winding design, while having a very high cross-sectional area, when high frequency current is applied, the current cannot flow over the entire cross-section due to skin effect and proximity effect, which is equivalent to bringing some high frequency additional resistance, i.e. alternating current resistance. For this reason, in the present application, an 8-layer flat wire winding design is preferably employed. Fig. 2 shows an 8-layer conductor structure. For ease of illustration, the layers are numbered sequentially from radially outward to inward herein, i.e., the layer located radially outermost is denoted as L1, followed by L2, L3, L4, L5, L6, L7, and then L8 located radially innermost. Again, this number is merely for ease of description and does not have any other particular meaning. Any other numbering scheme than that shown in fig. 2 may be used.

Unlike a motor using conductors having a circular cross-section, the stator winding 120 of the flat wire motor is formed by inserting a plurality of individual conductor elements from the slots 113 of the stator core 110 in the axial direction and then using a bending, welding, etc. process to form a complete stator winding. For this purpose, different forms of conductor elements may be employed to form the stator winding 120. When the conductor elements are inserted into the slots 113, the individual conductor elements can be closely arranged to each other due to their rectangular cross-section, which allows for a higher degree of conductor filling in one slot than in a conductor of circular cross-section.

Fig. 3 shows a schematic view of a conductor element for forming a stator winding. As can be seen from fig. 3, the conductor element has an overall U-shape. Specifically, the conductor element has two straight portions U-1, two bent portions U-2, and a connecting portion U-3 connecting the two straight portions U-1. In the initial state, the conductor element includes only two straight portions and a connecting portion U-3 connecting the straight portions. In manufacturing the stator winding, two straight portions are inserted into different tooth slots 113, respectively. After being inserted into place, the two straight portions are bent at one end axially outside the slot 113, thereby forming two bent portions U-2, and the portion not being bent becomes the straight portion U-1 shown in fig. 3.

Fig. 4 shows the arrangement of conductors in one tooth slot separately. As shown in fig. 4, 8 conductors are provided in sequence in the tooth slot 113 formed by two adjacent stator teeth 112, and the conductors shown correspond to the straight portions of the conductor element of fig. 3. The gullet 113 itself is also preferably rectangular in shape. In order to secure insulation, an insulating member, such as insulating paper, is provided between the conductor element and the inner wall of the slot 113. Insulating members 114 may be provided between adjacent conductors. The insulating member may be insulating paper or insulating varnish. The manner in which the insulating members are disposed in fig. 4 is merely illustrative and is not limiting of the manner in which the specific insulating members of the present application are disposed.

Returning again to fig. 1, the axially intermediate portion of the entire stator winding 120 corresponds to the straight portion of the conductor element. In the lower part of the stator winding 120 shown in fig. 1, the bent parts of the conductor elements are shown. Since the conductor element is soldered at the bent portion, the second end 1202 is also referred to as a soldered end. Accordingly, depending on the shape of the stator winding 120, the first end 1201 where the connection portion of the conductor element is located is also referred to as a crown end.

In order to supply current to the stator winding 120, the stator winding 120 is also provided with a plurality of lead-out wires. The lead-out wire is arranged at one side of the welding end, thereby reducing the axial space of the motor and improving the power density of the motor to a greater extent.

The inventors have realized that the prior art lead-out terminals or star terminals are far apart when designing the stator windings, which correspondingly increases the size of the bus bar, which is detrimental to integration with the bus bar. Meanwhile, when designing the stator winding, if the span design forms are various, the span designs correspondingly need a plurality of kinds of conductor elements, which makes the shaping and wire inserting processes of the conductor elements complex, thereby reducing the automatic production efficiency of the stator winding.

For this purpose, the application proposes the following stator windings. The stator winding adopts a three-phase winding, which is respectively U-phase, V-phase and W-phase, and the three phases adopt a star connection method. For each phase winding, one branch as shown in fig. 5, two branches as shown in fig. 6, or four branches not shown may be connected in parallel. Correspondingly, for different branch circuit setting modes, the application provides a corresponding winding structure, thereby solving the problems of the winding in the prior art, leading-out wire ends or star connection ends are relatively close, facilitating the design of a busbar, reducing the types of conductor elements and improving the automatic production efficiency.

Specifically, fig. 7 shows an expanded view of the U-phase winding connection where two branches of the stator winding are connected in parallel. In this expanded view, 48 gullets are shown, each having 8 wires therein. For ease of description, the numbering of the individual slots is shown with the numerals 1,2, 3, …,48 in the middle of the wire in each slot. The layer numbers of the 8-layer conductors are sequentially 1,2, 3,4, 5, 6, 7, and 8 in the order from the outside to the inside in the radial direction. In the developed view shown in fig. 7, the 8 wires in each slot correspond to L1-L8 in fig. 2, respectively, in left-to-right order, e.g., leftmost wire is L1 and rightmost wire is L8.

As can be seen from fig. 7, the U-phase winding adopts a two-path parallel connection mode, the first path has an access point u1_in and an extraction point u1_out, and the second path has an access point u2_in and an extraction point u2_out. For the first path, the wire connected to access point u1_in is located at layer 1 of slot 1, which is connected to layer 2 wire in slot 7, and then connected to layer 1 wire in slot 13. To more clearly describe the winding connection in fig. 7, the positions of the conductors are represented by m (n), where m represents the slot number, n represents the layer number, and "→" represents the connection relationship between the two wires, the two-way connection of the U-phase winding in fig. 7 is as follows:

For the first path ：U1_in→2(1)→8(2)→14(1)→20(2)→26(1)→32(2)→38(1)→44(2)——2(3)→8(4)→14(3)→20(4)→26(3)→32(4)→38(3)→44(4)——1(1)→7(2)→13(1)→19(2)→25(1)→31(2)→37(1)→43(2)——1(3)→7(4)→13(3)→19(4)→25(3)→31(4)→37(3)→43(4)——1(5)→7(6)→13(5)→19(6)→25(5)→31(6)→37(5)→43(6)——1(7)→7(8)→13(7)→19(8)→25(7)→31(8)→37(7)→43(8)——48(5)→6(6)→12(5)→18(6)→24(5)→30(6)→36(5)→42(6)——48(7)→6(8)→12(7)→18(8)→24(7)→30(8)→36(7)→42(8)→U1_out.

The number of slots of the stator winding that span between two active edges of the slots is referred to herein as the span. For example, if two edges are located in groove 1 and groove 7, respectively, then the span is 6; if the two edges are located in the 43 rd and 48 th slots, respectively, the span is 5.

Referring to fig. 7 and the above-mentioned winding method, from the access point, the portion of the phase winding between every 8 slots is defined as a winding period, and after the winding period is completed, the winding of the stator winding enters the next winding period, and is outgoing after 8 winding periods. Hereinabove, the demarcations between the individual winding cycles are shown by "-".

As can be seen from the above winding connection, the winding connection shown in fig. 7 has the following characteristics:

(1) In the same winding period, the conductors of the phase winding in different tooth grooves are positioned in two layers with continuous layer numbers or adjacent layers, and the layer numbers of the layers where the conductors in the two adjacent tooth grooves are positioned are different; for example, in the 1 st winding cycle or the 3 rd winding cycle, the layer numbers of the conductors in the adjacent two tooth grooves are respectively 1 and 2, the 1 st layer and the 2 nd layer are adjacent layers, the layer numbers 1 and 2 are continuous, and the layer numbers of the conductors in the respective tooth grooves are alternated among 1 and 2; in the 2 nd winding period or the 4 th winding period, the layer numbers of the conductors in the adjacent two tooth grooves are 3 and 4 respectively, and the layer numbers of the conductors in the tooth grooves are alternated among 3 and 4; in the 5 th winding period or the 7 th winding period, the layer numbers of the conductors in the adjacent two tooth grooves are 5 and 6 respectively, and the layer numbers of the conductors in the tooth grooves alternate between 5 and 6; in the 6 th winding period or the 8 th winding period, the layer numbers of the conductors in the adjacent two tooth grooves are respectively 7 and 8, and the layer numbers of the conductors in the tooth grooves are alternated among 7 and 8;

(2) Between two adjacent winding cycles, the winding follows the following law: the stride is 6 and the absolute value of the difference between layer numbers is 1, or the stride is 5 and the absolute value of the difference between layer numbers is 3. For example, 44

(2) -2 (3) Satisfies a span of 6 and the absolute value of the difference between layer numbers is 1, 43 (8) -48 (5) satisfies a span of 5 and the absolute value of the difference between layer numbers is 3;

(3) The spans of the stator windings are the same in the same winding period; in the winding method described above, the number is 6.

For the 2 nd path of the U-phase winding, the specific winding arrangement mode is as follows:

U2_in→48(8)→42(7)→36(8)→30(7)→24(8)→18(7)→12(8)→6(7)——48(6)→42(5)→36(6)→30(5)→24(6)→18(5)→12(6)→6(5)——1(8)→43(7)→37(8)→31(7)→25(8)→19(7)→13(8)→7(7)——1(6)→43(5)→37(6)→31(5)→25(6)→19(5)→13(6)→7(5)——1(4)→43(3)→37

(4)→31(3)→25(4)→19(3)→13(4)→7(3)——1(2)→43(1)→37(2)→31(1)→25(2)→19(1)→13(2)→7(1)——2(4)→44(3)→38(4)→32(3)→26(4)→20(3)→14(4)→8(3)——2(2)→44(1)→38(2)→32(1)→26(2)→20(1)→14(2)→8(1)→U2_out.

The winding connection mode of the U-phase 2 nd path also accords with the winding rule.

As known from the design of the winding aiming at the U phase, the type of the conductor element is greatly reduced due to single conductor span and layer number change in two adjacent tooth grooves, the production cost is reduced, and the winding efficiency is improved.

The stator winding adopts a three-phase symmetrical winding, so V, W phase winding modes are consistent with U phase, and only the numbers of the wire inlet and outlet slots are different. Fig. 8 shows a winding development of a V-phase winding matched to the U-phase winding of fig. 7, fig. 9 shows a winding development of a W-phase winding matched to the U-phase winding of fig. 7 and the V-phase winding of fig. 8, and fig. 10 shows a winding development of a complete stator winding.

As can be seen from fig. 10, the stator winding formed by the winding method according to the present invention has the wire-out ends thereof being closely spaced, so that the size of the bus bar can be reduced, thereby facilitating the integration of the bus bar.

Furthermore, it can be seen from the above winding pattern that the conductors belonging to the same phase are not arranged entirely in two adjacent tooth slots, but in three adjacent tooth slots. For example, for the 1 st tooth slot, all of the 1 st to 8 th layers are U-phase conductors, and of the 2 nd slots adjacent thereto, only 1, 2, 3, 4 th layers are arranged with U-phase conductors, and of the 48 th slots adjacent to the 1 st slot, there are U-phase conductors arranged at 5, 6, 7, 8 th layers. The winding mode corresponds to a short-distance winding, and can effectively weaken higher harmonics in the motor, so that the motor performance is further improved.

In addition, the application also provides a case of aiming at one branch, which is specifically as follows.

For the U-phase windings, the connection is (the first digit represents the slot number, and the number in brackets represents the number of winding layers):

U_in→2(1)→8(2)→14(1)→20(2)→26(1)→32(2)→38(1)→44(2)——2(3)→8(4)→14(3)→20(4)→26(3)→32(4)→38(3)→44(4)——1(1)→7(2)→13(1)→19(2)→25(1)→31(2)→37(1)→43(2)——1(3)→7(4)→13(3)→19(4)→25(3)→31(4)→37(3)→43(4)——1(5)→7(6)→13(5)→19(6)→25(5)→31(6)→37(5)→43(6)——1(7)→7(8)→13(7)→19(8)→25(7)→31(8)→37(7)→43(8)——48(5)→6(6)→12(5)→18(6)→24(5)→30(6)→36(5)→42(6)——48(7)→6(8)→12(7)→18(8)→24(7)→30(8)→36(7)→42(8)——48(8)→42(7)→36(8)→30(7)→24(8)→18(7)→12(8)→6(7)——48(6)→42(5)→36(6)→30(5)→24(6)→18(5)→12(6)→6(5)——1(8)→43(7)→37(8)→31(7)→25(8)→19(7)→13(8)→7(7)——1(6)→43(5)→37(6)→31(5)→25(6)→19(5)→13(6)→7(5)——1(4)→43(3)→37(4)→31(3)→25(4)→19(3)→13(4)→7(3)——1(2)→43(1)→37(2)→31(1)→25(2)→19(1)→13(2)→7(1)——2(4)→44(3)→38(4)→32(3)→26(4)→20(3)→14(4)→8(3)——2(2)→44(1)→38(2)→32(1)→26(2)→20(1)→14(2)→8(1)→U_out.

in the above winding manner, after each wire in 8 slots is connected, a winding cycle is formed by winding, the next winding will enter the next winding cycle, and the wires are wound for 16 winding cycles. Hereinabove, the demarcations between the individual winding cycles are shown by "-".

According to the above winding connection mode, the winding connection mode has the following characteristics:

(1) In the same winding period, the conductors of the phase winding in different tooth grooves are positioned in two layers with continuous layer numbers or adjacent layers, and the layer numbers of the layers where the conductors in the two adjacent tooth grooves are positioned are different; for example, in the 1 st, 3 rd, 14 th and 16 th winding cycles, the layer numbers of the conductors in two adjacent tooth grooves are respectively 1 and 2, the 1 st layer and the 2 nd layer are adjacent layers, the layer numbers 1 and 2 are continuous, and the layer numbers of the conductors in each tooth groove are alternated among 1 and 2; in the 2 nd, 4 th, 13 th and 15 th winding cycles, the layer numbers of the conductors in the adjacent two tooth grooves are 3 and 4 respectively, and the layer numbers of the conductors in the tooth grooves alternate among 3 and 4; in the 5 th, 7 th, 10 th and 12 th winding cycles, the layer numbers of the conductors in the adjacent two tooth grooves are 5 and 6 respectively, and the layer numbers of the conductors in the tooth grooves alternate between 5 and 6; in the 6 th, 8 th, 9 th and 11 th winding cycles, the layer numbers of the conductors in the adjacent two tooth grooves are respectively 7 and 8, and the layer numbers of the conductors in the tooth grooves are alternated among 7 and 8;

(2) The conductor in the last tooth slot in the 8 th winding period and the conductor in the first tooth slot in the 9 th winding period are positioned on the same layer with the same layer number, and the span of the winding between the two periods is 6; between two adjacent winding cycles, the winding follows the following law: the stride is 6 and the absolute value of the difference between layer numbers is 1, or the stride is 5 and the absolute value of the difference between layer numbers is 3. For example, 44

(2) -2 (3) Satisfies a span of 6 and the absolute value of the difference between layer numbers is 1, 43 (8) -48 (5) satisfies a span of 5 and the absolute value of the difference between layer numbers is 3;

(3) The spans of the stator windings are the same in the same winding period; in the winding method described above, the number is 6.

As a preferred embodiment, the layer number of the layer in which the conductor in the last slot in the 8 th winding cycle and the conductor in the first slot in the 9 th winding cycle are located is 8.

The stator winding adopts a three-phase symmetrical winding, so V, W phase winding modes are consistent with U phase, and only the numbers of the wire inlet and outlet slots are different.

In addition, the application also provides a situation of four paths in parallel connection, which is specifically as follows.

For the U-phase windings, the connection is (the first digit represents the slot number, and the number in brackets represents the number of winding layers):

U1_in→2(1)→8(2)→14(1)→20(2)→26(1)→32(2)→38(1)→44(2)——2(3)→8(4)→14(3)→20(4)→26(3)→32(4)→38(3)→44(4)——1(1)→7(2)→13(1)→19(2)→25(1)→31(2)→37(1)→43(2)——1(3)→7(4)→13(3)→19(4)→25(3)→31(4)→37(3)→43(4)→U1_out

U2_in→1(5)→7(6)→13(5)→19(6)→25(5)→31(6)→37(5)→43(6)——1(7)→7(8)→13(7)→19(8)→25(7)→31(8)→37(7)→43(8)——48(5)→6(6)→12(5)→18(6)→24(5)→30(6)→36(5)→42(6)——48(7)→6(8)→12(7)→18(8)→24(7)→30(8)→36(7)→42(8)→U2_out

U3_in→48(8)→42(7)→36(8)→30(7)→24(8)→18(7)→12(8)→6(7)——48(6)→42(5)→36(6)→30(5)→24(6)→18(5)→12(6)→6(5)——1(8)→43(7)→37(8)→31(7)→25(8)→19(7)→13(8)→7(7)——1(6)→43(5)→37(6)→31(5)→25(6)→19(5)→13(6)→7(5)→U3_out

U4_in→1(4)→43(3)→37(4)→31(3)→25(4)→19(3)→13(4)→7(3)——1(2)→43(1)→37(2)→31(1)→25(2)→19(1)→13(2)→7(1)——2(4)→44(3)→38(4)→32(3)→26(4)→20(3)→14(4)→8(3)——2(2)→44(1)→38(2)→32(1)→26(2)→20(1)→14(2)→8(1)→U4_out

The stator winding adopts a three-phase symmetrical winding, so V, W phase winding modes are consistent with U phase, and only the numbers of the wire inlet and outlet slots are different.

In the above winding manner, for each branch, from the access point, a portion of the phase winding between every 8 slots is defined as one winding period, and after the end of one winding period, the winding of the stator winding enters the next winding period, and is discharged after 4 winding periods in total. Hereinabove, the demarcations between the individual winding cycles are shown by "-".

According to the above winding connection mode, the winding connection mode has the following characteristics:

(1) In the same winding period, the conductors of the phase winding in different tooth grooves are positioned in two layers with continuous layer numbers or adjacent layers, and the layer numbers of the layers where the conductors in the two adjacent tooth grooves are positioned are different; for example, in the first branch, in the 1 st winding cycle or the 3 rd winding cycle, the layer numbers of the conductors in the adjacent two tooth grooves are respectively 1 and 2, the 1 st layer and the 2 nd layer are adjacent layers, the layer numbers 1 and 2 are continuous, and the layer numbers of the conductors in the tooth grooves are alternated among 1 and 2;

(2) Between two adjacent winding cycles, the winding follows the following law: the stride is 6 and the absolute value of the difference between layer numbers is 1, or the stride is 5 and the absolute value of the difference between layer numbers is 3. For example, 44

(2) -2 (3) Satisfies a span of 6 and the absolute value of the difference between layer numbers is1, 44 (4) -1 (1) satisfies a span of 5 and the absolute value of the difference between layer numbers is 3;

(3) The spans of the stator windings are the same in the same winding period; in the winding method described above, the number is 6.

As can be seen from the above-mentioned various winding modes, according to the stator winding of the present invention, the conductor span and layer number in two adjacent tooth slots are single in variation, so that the variety of conductor elements is greatly reduced, the production cost is reduced, and the winding efficiency is improved.

In addition, the stator winding formed by the winding mode has the advantages that the wire outlet ends are relatively close, so that the size of the bus bar can be reduced, and the bus bar is convenient to integrate.

According to the winding mode of the stator winding, the stator winding adopts a short-distance winding, so that higher harmonics in the motor can be effectively weakened, and the motor performance is further improved.

The motor having the stator winding of the present application can be applied to various types of electrically driven vehicles. For example, the present application may be applied to a battery-powered electric vehicle alone, or to a hybrid vehicle provided with a power source including other types in addition to an electric motor, such as a fossil fuel engine, a hydrogen engine, or the like. The stator winding can improve the slot filling rate of the winding and reduce the size of the stator winding, so that the motor has good heat dissipation, higher power density, smaller volume, higher automatic production efficiency and lower cost.

The structure of the present invention has been described in detail above. Those skilled in the art will recognize that many of the details described are exemplary only and not limiting. That is, it is only necessary to achieve the corresponding functions, and it is not necessary to employ the specific shape, structure, and the like described above.

While the present invention has been described with respect to the above exemplary embodiments, it will be apparent to those skilled in the art that various other embodiments can be devised by modifying the disclosed embodiments without departing from the spirit and scope of the invention. Such embodiments should be understood to fall within the scope of the invention as determined based on the claims and any equivalents thereof.

Claims (10)

1. A stator assembly, comprising:

a stator core having a plurality of slots provided at a radially inner side,

A stator winding composed of a plurality of conductor elements, a part of which is positioned in the tooth slot, and the conductor elements in each tooth slot of the plurality of tooth slots are sequentially arranged in a plurality of layers along the radial direction, the stator winding comprises a U-phase winding, a V-phase winding and a W-phase winding, the U-phase winding, the V-phase winding and the W-phase winding are formed by mutually connecting the plurality of conductor elements,

It is characterized in that the method comprises the steps of,

For each branch of each of the U-phase winding, the V-phase winding and the W-phase winding, the part of the branch of the phase winding in each 8 tooth slots from the access point is defined as a winding period, and in the same winding period, conductors in different tooth slots of the phase winding are positioned in two adjacent layers with different layer numbers, and the layer numbers of the layers where the conductors in the two adjacent tooth slots are positioned are different.

2. The stator assembly of claim 1 wherein the stator assembly is formed from a plurality of stator segments,

For each of the U-phase, V-phase and W-phase windings, two or four parallel paths are employed, the absolute value of the difference between the layer number of the conductor in the last slot in each winding cycle and the conductor in the first slot in the next winding cycle being 1 or 3.

3. The stator assembly of claim 1 wherein the stator assembly is formed from a plurality of stator segments,

For each of the U-phase, V-phase and W-phase windings, a branch is used, where only the conductor in the last slot of one winding cycle and the conductor in the first slot of the next winding cycle of the one winding cycle are located in the same layer number, and the absolute value of the difference between the layer numbers of the conductor in the last slot of each remaining winding cycle and the conductor in the first slot of the next winding cycle is 1 or 3.

4. A stator assembly according to claim 2 or 3, wherein,

When the absolute value of the difference between the layer number of the conductor in the last tooth slot in each winding period and the layer number of the conductor in the first tooth slot in the next winding period is 1, the span of the stator winding between the two tooth slots is 6;

When the absolute value of the difference between the layer number of the conductor in the last slot in each winding cycle and the layer number of the conductor in the first slot in the next winding cycle is 3, the span of the stator winding between the two slots is 5.

5. A stator assembly according to claim 1-3 wherein,

The stator windings are equally spaced in the same winding cycle.

6. The stator assembly of any one of claim 1 to 3, wherein,

The stator winding is provided with a crown end and a welding end, and the wire outlet end of each phase winding of the three-phase winding is positioned on the same side as the welding end.

7. The stator assembly of any one of claim 1 to 3, wherein,

The number of the tooth grooves is 48, and the number of the conductor element layers of the stator winding in each tooth groove is 8.

8. The stator assembly of any one of claim 1 to 3, wherein,

The conductor element comprises only U-shaped conductor elements.

9. The stator assembly of any one of claim 1 to 3, wherein,

The stator winding is a short distance winding.

10. An electric machine comprising a stator assembly according to any one of claims 1-9.