Odd layer flat wire stator assembly and motor

Abstract

The present application relates to the technical field of flat wire motor, and particularly relates to an odd layer flat wire stator assembly, the stator assembly comprises a stator core and a stator winding; the stator core is provided with A stator slots, the stator slots are sequentially arranged along the circumferential direction of the stator core, and are in annular array shape; the winding of the stator winding adopts rectangular conductors, and B layers of rectangular conductors are arranged in each stator slot along the radial direction of the stator core; wherein A is an integer, and B is an odd number greater than 3. The winding connection scheme of the stator winding provided by the present application is that the element number of each branch of the phase winding is the same, the phase slot number and the layer number passed by each branch are the same, and the balanced arrangement of the three-phase winding is realized. The odd layer flat copper wire motor provides more turn ratio selection for matching the performance of the motor, improves the output performance of the motor, solves the arrangement and connection problem of the even layer winding, and provides a good solution for the realization of the odd layer winding motor.

Description

Technical Field

[0001] This invention belongs to the field of flat wire motors, and specifically relates to an odd-layer flat wire stator assembly and motor. Background Technology

[0002] With the rapid development of new energy vehicles, permanent magnet synchronous motors have been widely used. As a core drive component of new energy vehicles, high efficiency, high speed, and high power density are the main development trends of permanent magnet synchronous motors.

[0003] In existing flat wire motor designs, the number of conductors in each stator slot is mostly even. Once the number of slots and conductors per slot are determined, the number of series turns in each phase winding can only be adjusted by the number of parallel branches to match the motor's performance. This approach has limitations. Because the number of conductors per slot is even, the selection of the number of series turns in each phase winding is limited, and the turn number matching cannot be optimized, affecting the motor's power and torque performance. To provide more options for turn number ratios and improve motor output performance, odd-layer winding motors are needed to address the aforementioned problems. Summary of the Invention

[0004] To address the above problems, the present invention provides an odd-numbered layer flat wire stator assembly, the stator assembly comprising a stator core and a stator winding; the stator core is provided with A stator slots, the stator slots being arranged sequentially along the circumference of the stator core in a circular array;

[0005] The stator windings use rectangular conductors, and B layers of rectangular conductors are arranged radially along the stator core in each stator slot; where A is an integer and B is an odd number greater than 3.

[0006] The connection methods of the stator windings at the hairpin end include: the first layer rectangular conductor of one stator slot and the first layer rectangular conductor of another stator slot are connected in a combined span manner; the second layer rectangular conductor of one stator slot and the third layer rectangular conductor of another stator slot are connected in a full-pitch span manner; the G layer rectangular conductor of one stator slot and the G+1 layer rectangular conductor of another stator slot are connected in a combined span manner; wherein, 3 < G < B, and G is an even number;

[0007] The connection method of the stator winding at the welding end includes: the H-th layer rectangular conductor of one stator slot and the H+1 layer rectangular conductor of another stator slot are connected in a full-pitch span manner; the B-th layer rectangular conductor of one stator slot and the B-th layer rectangular conductor of another stator slot are connected in a full-pitch span manner; wherein, 1≤H<B, and H is an odd number.

[0008] Furthermore, the combined span represents a mixed span method using full span, long span, and short span.

[0009] Furthermore, the formula for calculating the full pitch is: I = A / 2D; where I is the full pitch, A is the number of stator slots, and D is the number of pole pairs of the stator winding;

[0010] The formula for calculating the long pitch is: J = I + K; where J is the long pitch, I is the integer pitch, K is an integer, and 1 ≤ K < E, and E is the number of stator slots per pole per phase;

[0011] The formula for calculating the short pitch is: L = IK; where L is the short pitch, I is the whole pitch, K is an integer, and 1≤K<E, and E is the number of stator slots per pole per phase.

[0012] Furthermore, the average of the whole distance, long distance, and short distance used in the combined span is the whole distance value.

[0013] Furthermore, the stator winding is a three-phase winding, i.e., the number of phases C = 3; the number of pole pairs of the stator winding is D, the number of stator slots per pole per phase is E = A / (C*2D), and the number of parallel branches per phase winding is F, where F ≤ E.

[0014] Furthermore, the width of the stator slot opening is greater than the thickness of the B-layer rectangular conductor.

[0015] Furthermore, when the stator assembly outputs a lead at the card-out end, the lead and star-point line of the same branch at the welding end are connected. Any one of the card-out lines at the card-out end is divided into two I-pin lines, one of which can be used as a lead and the other as a star-point line.

[0016] The present invention also provides an electric motor, the electric motor including the stator assembly described above.

[0017] The beneficial effects of this invention are:

[0018] 1. The stator winding connection scheme provided by this invention ensures that the number of components in each branch of each phase winding is the same, and the number of phase slots and layers traversed by each branch is also the same, achieving a balanced arrangement of the three-phase windings. Odd-layer flat copper wire motors offer more turns ratio options to match motor performance, improving motor output performance; they also solve the problem of even-layer winding arrangement and connection, providing a well-manufacturable solution for odd-layer winding motors.

[0019] 2. The stator winding hairpin end winding provided by this invention has no hairpins connected to the same layer in the innermost layer, eliminating the need for layer-by-layer expansion, which facilitates wire forming, simplifies wiring, improves manufacturing process, and offers advantages in coil size. Furthermore, the welding end has no jumpers or cross wires, which is beneficial for motor structure layout and reduces the space size at the motor winding end.

[0020] 3. The slot width design of the stator slot provides space for the B-layer rectangular conductor to expand and twist inward. At the same time, the slot width design helps to reduce AC loss and improve motor efficiency.

[0021] 4. The stator winding provided by this invention can exit from either the welding end or the hairpin end. This enriches the winding schemes for odd-layer flat wire motors.

[0022] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 A schematic diagram of the stator assembly welding end in an embodiment of the present invention is shown;

[0025] Figure 2 It shows Figure 1 Enlarged diagram of part A in the diagram;

[0026] Figure 3 The diagram shows the structure of the stator slot.

[0027] In the diagram: 1-Stator core; 2-Stator slot; 3-Rectangular conductor; 4-Slot opening. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0029] This invention provides an odd-layer flat wire motor, including a rotor assembly and a stator assembly, wherein the rotor assembly is located inside the stator assembly.

[0030] Specifically, such as Figures 1-3As shown, the stator assembly includes a stator core 1 and a stator winding; the stator core 1 is generally cylindrical to accommodate the motor rotor assembly. The stator core 1 has several stator slots 2 arranged sequentially along the circumference of the stator core 1 in a circular array. The stator winding uses rectangular conductors 3.

[0031] Specifically, the stator winding can be divided into in-slot windings and end windings. The in-slot windings refer to the portion of the rectangular conductor located within the stator slots, with several layers of rectangular conductors arranged radially along the stator core in each slot. The end windings are paired at a certain span to connect the rectangular conductors at different positions within different stator slots, thereby achieving internal connections within the stator windings. The end windings are distributed on both sides of the stator core, namely the hairpin end and the welding end.

[0032] Furthermore, the winding method of the stator winding is determined by the connection method of the stator winding at the hairpin end and the connection method of the stator winding at the welding end.

[0033] In this embodiment of the invention, the stator core is provided with A stator slots; B layers of rectangular conductors are provided in each stator slot along the radial direction of the stator core, wherein A is an integer and B is an odd number greater than 3.

[0034] Furthermore, the stator winding is a three-phase winding, i.e., the number of phases C = 3; the number of poles of the stator winding is 2D, the number of stator slots per pole per phase is E = A / (C*2D), and the number of parallel branches per phase winding is F, where F ≤ E.

[0035] For ease of description, in this embodiment of the invention, the rectangular conductors in the same stator slot are sequentially defined as the first layer rectangular conductor, the second layer rectangular conductor, ..., the Bth layer rectangular conductor, according to the direction from the outer wall of the stator core to the axis of the stator core.

[0036] Specifically, the connection method of the stator winding at the hairpin end includes: the first layer rectangular conductor of one stator slot and the first layer rectangular conductor of another stator slot are connected in a combined span manner; the second layer rectangular conductor of one stator slot and the third layer rectangular conductor of another stator slot are connected in a full-pitch span manner; the G layer rectangular conductor of one stator slot and the G+1 layer rectangular conductor of another stator slot are connected in a combined span manner; wherein, 3 < G < B, and G is an even number.

[0037] The connection method of the stator winding at the welding end includes: the H-th layer rectangular conductor of one stator slot and the H+1 layer rectangular conductor of another stator slot are connected in a full-pitch span manner; the B-th layer rectangular conductor of one stator slot and the B-th layer rectangular conductor of another stator slot are connected in a full-pitch span manner; wherein, 1≤H<B, and H is an odd number.

[0038] Specifically, the combined span refers to a mixed span method that uses full span, long span, and short span.

[0039] The formula for calculating the full pitch is: I = A / 2D; where I is the full pitch, A is the number of stator slots, and D is the number of pole pairs of the stator winding.

[0040] The formula for calculating the long distance is: J = I + K; where J is the long distance, I is the integer distance, K is an integer, and 1 ≤ K < E, and E is the number of stator slots per pole per phase.

[0041] The formula for calculating the short pitch is: L = IK; where L is the short pitch, I is the whole pitch, K is an integer, and 1≤K<E, and E is the number of stator slots per pole per phase.

[0042] Specifically, the average of the whole distance, long distance, and short distance used in the combined span is the whole distance value.

[0043] For example, the stator assembly uses a combination of three spans: full span I, first long span J1, and first short span L1, which satisfies (I+J1+L1) / 3=I.

[0044] For example, if the stator assembly uses a combination of five spans including full span I, first long span J1, second long span J2, first short span L1 and second short span L2, then (I+J1+J2+L1+L2) / 5=I.

[0045] It should be noted that the two rectangular conductors in the slot winding are connected by a hairpin end or a welding end. Along the circumference of the stator core, the number of stator slots between these two rectangular conductors plus one represents the span between the two rectangular conductors at the hairpin end or welding end.

[0046] The innermost layer of the stator winding hairpin end winding has no hairpins connected to the same layer, so there is no need for layer-by-layer expansion, which is conducive to wire forming, simple wire insertion, good manufacturing process, and the coil size is more advantageous.

[0047] The above-mentioned stator winding connection scheme ensures that each branch of each phase winding has the same number of components, and each branch passes through the same number of phase slots and layers, achieving a balanced arrangement of the three-phase windings. Odd-layer flat copper wire motors offer more turns ratio options to match motor performance, improving motor output performance; they also solve the connection problem of even-layer windings, providing a well-manufacturable solution for odd-layer winding motors.

[0048] Preferred, Figure 2 and Figure 3 As shown, the width m of the slot opening 4 of the stator slot is greater than the thickness n of the rectangular conductor 3 of the B layer.

[0049] Specifically, the innermost rectangular conductors of the stator winding at the welding end are layered by cross-flaring. The cross-flaring method is as follows: Each pole and phase has E rectangular conductors of the B-th layer, constituting one small unit. There are a total of P = A / E small units along the circumference of the stator core. Flaring is performed inward from any small unit along the inner circumference of the stator core, while adjacent small units remain unchanged. Flaring is then performed cross-flaring sequentially. That is, two small units adjacent to a unit undergoing flaring are not flared, while two small units adjacent to a unit not flared are flared. After flaring, all B-th layer rectangular conductors are distributed in two layers at the welding end. The layered B-th layer rectangular conductors are then twisted and connected according to the stator winding connection method described above at the welding end.

[0050] The slot width design of the stator slot provides space for the B-layer rectangular conductor to flare inward and turn, while the slot width design helps to reduce AC loss and improve motor efficiency.

[0051] The stator winding provided by this invention has no hairpins connected to the same layer in the innermost layer of the hairpin end winding, eliminating the need for layer-by-layer expansion, which facilitates wire forming, simplifies wiring, improves manufacturing process, and offers advantages in coil size. Furthermore, the absence of jumpers or cross wires at the welding end facilitates motor structural layout and reduces the space required at the motor winding ends.

[0052] More preferably, when the stator assembly outputs a wire at the card-out end, the lead wire and the star-point wire of the same branch at the welding end are connected, and any one of the card-out wires at the card-out end is divided into two I-pin wires. Any one of the I-pin wires can be used as a lead wire, and the other I-pin wire can be used as a star-point wire.

[0053] The stator assembly can have wires exiting from either the welding end or the hairpin end. This enriches the winding schemes for odd-layer flat wire motors.

[0054] Further preferred, such as Figure 1 and Figure 2 As shown, the stator slots of the stator assembly have an unequal width slot structure. This further enriches the winding schemes for odd-layer flat wire motors.

[0055] Example 1

[0056] This embodiment provides a three-phase motor stator. The stator core has 72 stator slots and 4 pole pairs. The stator windings include three-phase windings (X, Y, and Z), with 3 stator slots per pole and 3 parallel branches. Each stator slot contains 5 layers of rectangular conductors. That is, A=72, D=4, C=3, E=3, F=3, B=5. The stator assembly's lead-out points are located at the welded ends.

[0057] For ease of description, all stator slots on the stator core are sequentially arranged in a circumferential direction and are denoted as A1, A2, A3, ..., A72. A1(1) represents the first layer of rectangular conductor in stator slot A1.

[0058] The first branch winding route of the X-phase winding is as follows:

[0059] A38(2)→A47(3)→A38(4)→A48(5)→A57(5)→A49(4)→A58(3)

[0060] →A49(2)→A58(1)→A65(1)→A56(2)→65(3)→A56(4)→A65(5)→A2(5)→A65(4)→A2(3)→A65(2)→A2(1)→A12(1)→A3(2)→A12(3)→A3(4)→A12(5)→A21(5)→A12(4)→A21(3)→A12(2)→A21(1)→A31(1)→A22(2)→A31(3)→A22(4)→A31(5)→A40(5)→A31(4)→A40(4)→A31(2)→A40(1)→A47(1).

[0061] The second branch winding route of the X-phase winding is as follows:

[0062] A39(2)→A48(3)→A39(4)→A49(5)→A58(5)→A47(4)→A56(3)

[0063] →A47(2)→A56(1)→A66(1)→A57(2)→A66(3)→A57(4)→A66(5)→A3(5)→A66(4)→A3(3)→A66(2)→A3(1)→A13(1)→A4(2)→A13(3)→A4(4)→A13(5)→A22(5)→A13(4)→A22(3)→A13(2)→A22(1)→A29(1)→A20(2)→A29(3)→A20(4)→A29(5)→A38(5)→A29(4)→A38(3)→A29(2)→A38(1)→A48(1).

[0064] The winding path of the third branch of the X-phase winding is as follows:

[0065] A40(2)→A49(3)→A40(4)→A47(5)→A56(5)→A48(4)→A57(3)

[0066] →A48(2)→A57(1)→A67(1)→A58(2)→A67(3)→A58(4)→A67(5)→A4(5)→A67(4)→A4(3)→A67(2)→A4(1)→A11(1)→A2(2)→A11(3)→A2(4)→A11(5)→A20(5)→A11(4)→A20(3)→A11(2)→A20(1)→A30(1)→A21(2)→A30(3)→A21(4)→A30(5)→A39(5)→A30(4)→A39(3)→A30(2)→A39(1)→A49(1).

[0067] According to the above winding path design, the number of elements in each branch of each phase winding of the stator winding is the same, the number of phase slots and layers passed through each branch is the same, which basically achieves the same back EMF phase and magnitude in each branch, and the same resistance and inductance at the beginning and end of each branch, thus realizing the balanced arrangement of the three-phase winding.

[0068] Example 2

[0069] This embodiment provides a three-phase motor stator. The stator core has 72 stator slots and 4 pole pairs. The stator windings include three-phase windings (X, Y, and Z), with 3 stator slots per pole and 3 parallel branches. Each stator slot contains 5 layers of rectangular conductors. That is, A=72, D=4, C=3, E=3, F=3, B=5. The stator assembly's lead-out position is at the hairpin end.

[0070] When the stator assembly outputs a lead at the card-out end, the lead and star-point line of the same branch at the welding end are connected. Any one of the card-out lines at the card-out end is divided into two I-pin lines. Any one of the I-pin lines can be used as a lead, and the other I-pin line can be used as a star-point line.

[0071] For ease of description, all stator slots on the stator core are sequentially arranged in a circumferential direction and are denoted as A1, A2, A3, ..., A72. A1(1) represents the first layer of rectangular conductor in stator slot A1.

[0072] The first branch winding route of the X-phase winding is as follows:

[0073] A47(1)→A38(2)→A47(3)→A38(4)→A48(5)→A57(5)→A49(4)

[0074] →A58(3)→A49(2)→A58(1)→A65(1)→A56(2)→65(3)→A56(4)→A65(5)→A2(5)→A65(4)→A2(3)→A65(2)→A2(1)→A12(1)→A3(2)→A12(3)→A3(4)→A12(5)→A21(5)→A12(4)→A21(3)→A12(2)→A21(1)→A31(1)→A22(2)→A31(3)→A22(4)→A31(5)→A40(5)→A31(4)→A40(4)→A31(2)→A40(1).

[0075] The second branch winding route of the X-phase winding is as follows:

[0076] A48(1)→A39(2)→A48(3)→A39(4)→A49(5)→A58(5)→A47(4)

[0077] →A56(3)→A47(2)→A56(1)→A66(1)→A57(2)→A66(3)→A57(4)→A66(5)→A3(5)→A66(4)→A3(3)→A66(2)→A3(1)→A13(1)→A4(2)→A13(3)→A4(4)→A13(5)→A22(5)→A13(4)→A22(3)→A13(2)→A22(1)→A29(1)→A20(2)→A29(3)→A20(4)→A29(5)→A38(5)→A29(4)→A38(3)→A29(2)→A38(1).

[0078] The winding path of the third branch of the X-phase winding is as follows:

[0079] A49(1)→A40(2)→A49(3)→A40(4)→A47(5)→A56(5)→A48(4)

[0080] →A57(3)→A48(2)→A57(1)→A67(1)→A58(2)→A67(3)→A58(4)→A67(5)→A4(5)→A67(4)→A4(3)→A67(2)→A4(1)→A11(1)→A2(2)→A11(3)→A2(4)→A11(5)→A20(5)→A11(4)→A20(3)→A11(2)→A20(1)→A30(1)→A21(2)→A30(3)→A21(4)→A30(5)→A39(5)→A30(4)→A39(3)→A30(2)→A39(1).

[0081] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. An odd-layer flat wire stator assembly, characterized in that, The stator assembly includes a stator core and a stator winding; the stator core is provided with A stator slots, which are arranged sequentially along the circumference of the stator core in a circular array. The stator windings use rectangular conductors, and B layers of rectangular conductors are arranged radially along the stator core in each stator slot; where A is an integer and B is an odd number greater than 3. The connection methods of the stator windings at the hairpin end include: the first layer rectangular conductor of one stator slot and the first layer rectangular conductor of another stator slot are connected in a combined span manner; the second layer rectangular conductor of one stator slot and the third layer rectangular conductor of another stator slot are connected in a full-pitch span manner; the G layer rectangular conductor of one stator slot and the G+1 layer rectangular conductor of another stator slot are connected in a combined span manner; wherein, 3 < G < B, and G is an even number, wherein the combined span means using a mixed span method of full pitch, long pitch and short pitch, and the formula for calculating the full pitch is: I = A / 2D; where I is the full pitch, A is the number of stator slots, and D is the number of pole pairs of the stator winding; The formula for calculating the long pitch is: J = I + K; where J is the long pitch, I is the integer pitch, K is an integer, and 1 ≤ K < E, and E is the number of stator slots per pole per phase; The formula for calculating the short pitch is: L=IK; where L is the short pitch, I is the whole pitch, K is an integer, and 1≤K<E, where E is the number of stator slots per pole per phase; The connection method of the stator winding at the welding end includes: the H-th layer rectangular conductor of one stator slot and the H+1 layer rectangular conductor of another stator slot are connected in a full-pitch span manner; the B-th layer rectangular conductor of one stator slot and the B-th layer rectangular conductor of another stator slot are connected in a full-pitch span manner; wherein, 1≤H<B, and H is an odd number.

2. The odd-layer flat wire stator assembly according to claim 1, characterized in that, The average of the whole span, long span, and short span used in the combined span is the whole span value.

3. The odd-layer flat wire stator assembly according to claim 1, characterized in that, The stator winding is a three-phase winding, i.e., the number of phases C=3; the number of pole pairs of the stator winding is D, and the number of stator slots per pole per phase is E=A / (C 2D), the number of parallel branches of each phase winding is F, where F≤E.

4. The odd-layer flat wire stator assembly according to claim 1, characterized in that, The width of the stator slot opening is greater than the thickness of the B-layer rectangular conductor.

5. The odd-layer flat wire stator assembly according to claim 1, characterized in that, When the stator assembly outputs a lead at the card-out end, the lead and star-point line of the same branch at the welding end are connected. Any one of the card-out lines at the card-out end is divided into two I-pin lines, one of which can be used as a lead and the other as a star-point line.

6. An electric motor, characterized in that, The motor includes the stator assembly described in any one of claims 1-5.

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