Four-path parallel short-distance flat wire winding and motor

Abstract

The invention relates to a four-path parallel short-distance flat wire winding, which comprises a U-phase winding, a V-phase winding and a W-phase winding, each phase winding comprises four branches which are arranged in parallel, the flat wire windings are arranged in each stator tooth groove in eight layers, the flat wire windings are only made of U-pins, two leg parts of each U-pin are positioned on two adjacent layers, and the two leg parts of each U-pin are positioned on two adjacent layers. The flat wire winding has and only has three spans. In the stator winding, the wire outlet side and the welding side are on the same side, so that the axial length of the motor can be reduced, and the space is saved; a four-path parallel winding mode is adopted, the defects that the number of turns of series connection of each phase is high, thermal load is large and high-rotating-speed power is reduced quickly due to the fact that one branch or two branches are connected in parallel are overcome, potential balance can be achieved in the four-pair-pole winding of each phase, current cannot be generated due to potential balance, and in-phase ring current is avoided; the specification number of the U-pins is small, the complexity of the manufacturing process is reduced, and the manufacturing efficiency is improved.

Description

Technical Field

[0001] The invention relates to the technical field of motors, and in particular to a four-way parallel short-distance flat wire winding and a motor. Background Art

[0002] With the development of electric vehicle technology, the performance requirements for electric vehicle drive motors are getting higher and higher, and the power density of drive motors is constantly increasing. The existing enameled round copper wire has gaps between the outer circles, which limits the improvement of the slot fill rate and can no longer meet the performance requirements of current automotive motors. Compared with round windings, flat wires are first made into a hairpin-like shape, then inserted into the stator slots, and then out from the other end, and the ends of the hairpins are welded together, which improves the slot fill rate and thus improves the motor performance.

[0003] At present, the flat wire technology in the automotive industry is relatively mature, with 4 / 6 / 8 / 10-layer flat wire designs, but most motors have only 1 or 2 parallel stator windings, and too many turns make it difficult to increase high-speed power. In order to increase power while ensuring efficiency, multi-way parallel design has become an inevitable choice. Summary of the invention

[0004] To this end, the present invention proposes a four-way parallel short-distance flat wire winding and a motor, and the specific scheme is as follows.

[0005] A four-way parallel short-distance flat wire winding includes a U-phase winding, a V-phase winding and a W-phase winding, and each phase winding includes four branches arranged in parallel. The flat wire winding is arranged in 8 layers in each stator tooth slot. The flat wire winding is made of only U-pins, and the two legs of each U-pin are located in two adjacent layers. The flat wire winding has only three spans.

[0006] According to one aspect of the present invention, the three spans are 5, 6, and 7 respectively.

[0007] According to one aspect of the present invention, the number of spans 6 is the largest and the number of spans 7 is the smallest.

[0008] According to one aspect of the present invention, within each branch, the number of spans 5 is greater than the number of spans 7 by one.

[0009] According to one aspect of the present invention, each of the four parallel branches of each phase winding has four periods, and the periods in each branch have the same span variation mode.

[0010] According to one aspect of the present invention, for the first branch and the third branch of the four branches of each phase winding, the span variation pattern is 7-6-5-6-7-6-5 in each cycle.

[0011] According to one aspect of the present invention, for the second branch and the fourth branch of the four branches of each phase winding, the span variation pattern is 5-6-7-6-5-6-7 in each cycle.

[0012] According to one aspect of the present invention, for each of the four branches of each phase winding, the spans between two periods connected to each other are 6, 5, and 6 respectively.

[0013] The present invention also provides a motor, comprising a rotor assembly and a stator assembly, wherein the stator assembly has the above-mentioned four-way parallel short-distance flat wire windings.

[0014] The present invention also proposes an electric drive system, comprising at least one of a reducer and an inverter, and the above-mentioned motor.

[0015] As can be seen from the above, the present invention proposes a stator winding with 48 slots and 8 layers, which has the following advantages:

[0016] (1) The four-way parallel connection avoids the disadvantages of high number of series turns per phase, large heat load, and rapid power drop at high speed that exist in the parallel connection of one branch or two branches;

[0017] (2) The outlet side and the welding side are on the same side, which can reduce the axial length of the motor and save space;

[0018] (3) Only one type of conductor element is used, and the number of spans is only three, which greatly reduces the specifications of the conductor elements, reduces the complexity of the manufacturing process, and improves the manufacturing efficiency;

[0019] (4) The potential is balanced within the four pole pairs of each phase winding, thereby eliminating the circulating current within the phase.

[0020] Other features and advantages of the present invention will be described in detail below in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Exemplary embodiments of the present invention are described with reference to the accompanying drawings, in which:

[0022] Figure 1 A perspective view of a stator assembly according to an embodiment of the present invention is shown.

[0023] Figure 2 The nomenclature of the tooth grooves and layer numbers is shown schematically.

[0024] Figure 3 The expanded design diagram of the stator winding of the present invention is shown.

[0025] Figure 4 The U-phase development design diagram of the stator winding of the present invention is shown.

[0026] Figure 5 The V-phase development design diagram of the stator winding of the present invention is shown.

[0027] Figure 6 The W-phase development design diagram of the stator winding of the present invention is shown.

[0028] All the drawings are only schematic and not necessarily drawn to scale, and they only show those parts necessary for explaining the present invention, and other parts are omitted or only mentioned. That is, in addition to the parts shown in the drawings, the present invention may also include other parts.

[0029] In the figures, identical and / or functionally identical technical features are provided with identical or similar reference numerals. DETAILED DESCRIPTION

[0030] Embodiments of the present invention are described below with reference to the accompanying drawings. In the following description, many specific details are set forth so that those skilled in the art can more fully understand and implement the present invention. However, it will be apparent to those skilled in the art that the present invention may be implemented without some of these specific details. In addition, it should be understood that the present invention is not limited to the specific embodiments described. On the contrary, any combination of the features and elements described below may be considered to implement the present invention, regardless of whether they relate to different embodiments. Therefore, the following aspects, features, embodiments and advantages are intended for illustration purposes only and should not be considered as features or limitations of the claims unless explicitly stated in the claims.

[0031] In the following description, the descriptions about directions, such as "upper", "lower", "inner", "outer", "radial", "axial", etc., which may be used, are only for the convenience of description, unless otherwise specified, and are not intended to form any limitation on the technical solution of the invention. In addition, in the following description, terms such as "first", "second", etc. are used to describe the elements of the present application, and these terms are only used to distinguish the elements, and are not intended to limit the nature, sequence, order or number of these elements.

[0032] Figure 1 FIG. 1 shows a three-dimensional view of a stator assembly according to an embodiment of the present invention. The stator assembly includes a stator core 1 and a stator winding 2. Figure 1 It can be seen from the figure that the outlet end of the stator winding is designed at the welding end. In addition, the stator winding of the present invention is made of U-pin only.

[0033] Furthermore, the stator core 1 of the present invention has 48 stator slots, and 8 layers of conductors are arranged in each stator slot. Figure 2 As shown. Figure 2In the embodiment, the stator slots are numbered in a counterclockwise direction, and the layer numbers in the stator slots are numbered from the 1st layer to the 8th layer from the outside to the inside in the radial direction.

[0034] The following combination Figure 3-Figure 6 The design of the stator winding of the present invention is described in detail.

[0035] In the present invention, the stator winding includes a U phase, a V phase and a W phase, and each phase winding adopts a four-way parallel connection mode. As an important improvement of the present invention, the present invention, while adopting a four-way parallel winding design, also enables the winding to form a potential balance in the four pairs of poles of each phase winding, thereby eliminating the intra-phase circulating current. Therefore, the problem of intra-phase circulating current is solved, and the defect of low parallel branch number does not exist.

[0036] Specifically, since a three-phase winding is used, the connection relationship of each phase winding is the same, and the only difference is the starting position. In the embodiment to be described below, the V-phase incoming line is spaced 4 tooth slots from the U-phase incoming line, and the W-phase incoming line is spaced 4 tooth slots from the V-phase incoming line.

[0037] Taking the U phase as an example, it includes 4 branches, namely U1, U2, U3 and U4. The winding methods of the four branches are as follows:

[0038] U1_in→1(1)→8(2)→14(1)→19(2)→25(1)→32(2)→38(1)→43(2)→1(3)→8(4)→14(3)→19(4)→25(3)→32(4)→38(3)→43(4)→4 8(5)→7(6)→13(5)→18(6)→24(5)→31(6)→37(5)→42(6)→48(7)→7(8)→13(7)→18(8)→24(7)→31(8)→37(7)→42(8)→U1_out;

[0039] U2_in→2(1)→7(2)→13(1)→20(2)→26(1)→31(2)→37(1)→44(2)→2(3)→7(4)→13(3)→20(4)→26(3)→31(4)→37(3)→44(4)→ 1(5)→6(6)→12(5)→19(6)→25(5)→30(6)→36(5)→43(6)→1(7)→6(8)→12(7)→19(8)→25(7)→30(8)→36(7)→43(8)→U2_out;

[0040] U3_in→1(8)→42(7)→36(8)→31(7)→25(8)→18(7)→12(8)→7(7)→1(6)→42(5)→36(6)→31(5)→25(6)→18(5)→12(6)→7(5)→ 2(4)→43(3)→37(4)→32(3)→26(4)→19(3)→13(4)→8(3)→2(2)→43(1)→37(2)→32(1)→26(2)→19(1)→13(2)→8(1)→U3_out;

[0041] U4_in→48(8)→43(7)→37(8)→30(7)→24(8)→19(7)→13(8)→6(7)→48(6)→43(5)→37(6)→30(5)→24(6)→19(5)→13(6)→6(5) →1(4)→44(3)→38(4)→31(3)→25(4)→20(3)→14(4)→7(3)→1(2)→44(1)→38(2)→31(1)→25(2)→20(1)→14(2)→7(1)→U4_out.

[0042] According to the winding method described above, calculations show that for each phase branch, potential balance can be achieved within the four-pole winding, so there is no potential difference, and no current will be generated. As a result, while using a high number of parallel branches, the intra-phase circulating current is eliminated.

[0043] In addition, the stator winding of the present invention also has the following characteristics:

[0044] Feature 1: In terms of span, for the four cycles of each branch, the span changes in each cycle in the same way. For example, in the U1 branch, the span changes in the same way as 7-6-5-6-7-6-5, while in the U2 branch, the span changes in the same way as 5-6-7-6-5-6-7.

[0045] Feature 2: In terms of span, the span change method of the first branch and the third branch is the same, and the span change method of the second branch and the fourth branch is the same.

[0046] Feature 3: In the entire winding, there are only three spans, namely 5, 6, and 7, so the number of spans is very small. It can be further seen that the number of spans 6 is the largest and the number of spans 7 is the smallest. Furthermore, in each branch, the number of spans 5 is 1 more than the number of spans 7. This makes the specifications of the corresponding conductor components, namely U-pins, very small, so that the manufacturing process is relatively simpler and the manufacturing efficiency is also higher.

[0047] Feature 4: In terms of the number of layers, the two legs of each U-pin are located on two adjacent layers, which also reduces the specifications of the U-pin and improves manufacturing efficiency.

[0048] It can be seen from the above that in the stator winding of the present invention, the outgoing line side and the welding side are on the same side, which can reduce the axial length of the motor and save space; the four-way parallel winding method is adopted to avoid the shortcomings of high number of series turns per phase, large heat load, and rapid power drop at high speed that exist in one branch or two branches in parallel, and potential balance can be achieved in the four-pole winding of each phase, and potential balance will not generate current, thereby avoiding intra-phase circulation; the number of U-pin specifications is small, which reduces the complexity of the manufacturing process and improves manufacturing efficiency.

[0049] The motor with the stator winding of the present application can be applied to various types of electric vehicles, for example, it can be applied to pure electric vehicles that are only powered by batteries, or it can be applied to hybrid vehicles that are equipped with other types of power sources in addition to the motor.

[0050] The present invention has been clearly and completely described with reference to the above exemplary embodiments, and it should be understood by those skilled in the art that various other embodiments can be conceived by modifying the disclosed technical solutions without departing from the spirit and scope of the present invention. These embodiments should be understood to fall within the scope of the present invention determined based on the claims and any equivalent technical solutions thereof.

Claims

1. A four-way parallel short-distance flat wire winding, comprising a U-phase winding, a V-phase winding and a W-phase winding, wherein each phase winding comprises four branches arranged in parallel, wherein the flat wire winding is arranged in 8 layers in each stator tooth slot, characterized in that: The flat wire winding is made of U-pin only, and the two legs of each U-pin are located in two adjacent layers. The flat wire winding has only three spans.

2. The four-way parallel short-distance flat wire winding according to claim 1, characterized in that: The three spans are 5, 6, and 7 respectively.

3. The four-way parallel short-distance flat wire winding according to claim 2, characterized in that: Span 6 has the largest number, and span 7 has the least number.

4. The four-way parallel short-distance flat wire winding according to claim 3, characterized in that: In each branch, the number of spans 5 is greater than the number of spans 7 by 1.

5. The four-way parallel short-distance flat wire winding according to any one of claims 1 to 4, characterized in that: Each of the four parallel branches of each phase winding has four periods, and the periods in each branch have the same span variation mode.

6. The four-way parallel short-distance flat wire winding according to claim 5, characterized in that: For the first and third branches of the four branches of each phase winding, the span changes in each cycle in the manner of 7-6-5-6-7-6-5.

7. The four-way parallel short-distance flat wire winding according to claim 5, characterized in that: For the second and fourth branches of the four branches of each phase winding, the span changes in each cycle in the manner of 5-6-7-6-5-6-7.

8. The four-way parallel short-distance flat wire winding according to claim 6 or 7, characterized in that: For each of the four branches of each phase winding, the spans between two cycles connected to each other are 6, 5, and 6 respectively.

9. An electric motor, comprising a rotor assembly and a stator assembly, wherein the stator assembly has a four-way parallel short-distance flat wire winding according to any one of claims 1 to 8.

10. An electric drive system, comprising at least one of a reducer and an inverter, characterized in that: Also included is the motor according to claim 9.

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