Short-distance winding motor
By using short-range winding and reverse twisting methods in the flat wire motor of new energy vehicles, the problems of high harmonic content and poor NVH performance caused by the whole distance winding are solved, and the harmonic content of the motor and the improvement of NVH performance are achieved.
Patent Information
- Application Number
- CN202510107806.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Priority Date
- 2024-12-05
- Filing Date
- 2025-01-23
- Publication Date
- 2025-05-02
AI Technical Summary
The motors caused by the full distance winding in existing new energy vehicle flat wire motors have high harmonic content, large torque fluctuations, and poor noise, vibration and acoustic and vibrating roughness (NVH) performance.
The short-range winding method is adopted to change the span of the coil, and the magnetic field distribution is more uniform, the harmonic components in the magnetic field are reduced, and the number of bridge lines is reduced through the reverse twisting method, reducing the weight and cost of the motor.
It effectively reduces the 5th and 7th harmonic content of the motor, reduces the cogging torque and the torque pulsation of the load, reduces the back-potential harmonic distortion rate, and significantly improves the NVH performance of the motor.
Smart Images
Figure CN119921490A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to a flat wire motor stator winding for new energy vehicles, and in particular to a short-pitch winding motor. Background Art
[0002] Currently, most flat wire motors for new energy vehicles use full-pitch windings, which have large harmonic content, resulting in large torque fluctuations in the motor and poor noise, vibration, and harshness (NVH) performance.
[0003] Therefore, it is necessary to adopt a new short-pitch winding method for motors with P-level logarithm, Z-number of slots, X-layer flat wire, and Q-number of slots per pole per phase to improve the 5th and 7th harmonic content of the motor, reduce the motor cogging torque, load torque pulsation and back-EMF harmonic distortion rate, and greatly improve the NVH performance of the motor. Summary of the invention
[0004] The object of the present invention is to provide a short-pitch winding motor to improve the harmonic content of the motor, reduce the motor cogging torque, load torque pulsation and back-EMF harmonic distortion rate, and improve the NVH performance of the motor.
[0005] In order to solve the above technical problems, an embodiment of the present invention provides a short-pitch winding motor, including a motor stator, a motor rotor, a motor shaft, a bearing, and a flat wire; the bearing is arranged on the motor shaft, and the motor rotor is connected to the motor stator through the bearing; the intermediate logarithm of the motor is P, the total number of slots is Z, the number of slots per pole per phase is Q, and the number of slot layers is X; wherein P is a positive number greater than or equal to 4, Z=Q*P*3, and X is an even number ≥2; the flat wire is arranged in a short-pitch winding manner, specifically including that two consecutive adjacent slot layers in an even number of slot layers are regarded as a slot layer group, and the first slot layer in each slot layer group is arranged in the first slot layer. On the second slot layer; in any slot layer group, the nth stator slot of the first slot layer is connected to the n+5th stator slot of the second slot layer by a flat wire; between the slot layer groups, the nth stator slot of the second slot layer of the Mth slot layer group is connected to the n+7th stator slot of the first slot layer of the M+1th slot layer group by a flat wire; in the outermost slot layer, the m+1th stator slot on the right side of the lead-out stator slot m is connected to the m-6th stator slot on the left side of the lead-in stator slot m-5 by a flat wire; in the innermost slot layer, the flat wire after one turn of winding is reversed and reconnected to the innermost slot layer; wherein n, m, and M are all integers ≥1.
[0006] In addition, in one example, the short-pitch winding motor is a three-phase motor, including three phases U, V, and W; the flat wire winding methods of the three phases U, V, and W are all the short-pitch winding methods; the V-phase flat wire winding is set to increase the number of slots by 4 in a clockwise direction in accordance with the U-phase winding; the W-phase flat wire winding is set to increase the number of slots by 4 in a clockwise direction in accordance with the V-phase winding.
[0007] In addition, in one example, the motor stator includes stator silicon steel punchings, insulating paper, bridge wires, and three-phase line connection terminals; the insulating paper is arranged in the stator slots of the silicon steel punchings; the bridge wires link the three-phase branches and are connected to the three-phase line connection terminals.
[0008] In addition, in one example, the stator silicon steel punching sheets are formed by stacking silicon steel sheets with a thickness of 0.2-0.27 mm.
[0009] In addition, in one example, the insulating paper is distributed in Z slots.
[0010] Compared with the prior art, the present invention replaces the full-pitch winding method in the prior art with a short-pitch winding method. The short-pitch winding changes the span of the coil, which can make the magnetic field distribution more uniform and reduce the harmonic components in the magnetic field. And because the short-pitch winding optimizes the magnetic field distribution, the amplitude of the harmonic potential inside the motor can be reduced. In addition, the short-pitch winding design can effectively reduce the generation of high-order harmonics and reduce the impact of harmonics on the operation of the motor. And a reverse twisting method is adopted to achieve connection between the same phases, reduce the number of bridge wires, and thus reduce the weight and cost of the motor. BRIEF DESCRIPTION OF THE DRAWINGS
[0011] Figure 1 A schematic diagram of a motor connection structure according to an embodiment of the present invention;
[0012] Figure 2 A schematic diagram of a winding connection structure according to an embodiment of the present invention;
[0013] Figure 3 For one embodiment of the present invention, Figure 2 It is a schematic diagram of the connection structure of the V-phase winding of the U-phase;
[0014] Figure 4 For one embodiment of the present invention, Figure 2 It is a schematic diagram of the connection structure of the W-phase winding of the U-phase;
[0015] Figure 5 Schematic diagram of a three-phase winding of a motor according to an embodiment of the present invention. DETAILED DESCRIPTION
[0016] To make the purpose, technical scheme and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. However, it will be appreciated by those skilled in the art that in the embodiments of the present invention, many technical details are proposed in order to enable the reader to better understand the present application. However, even without these technical details and various changes and modifications based on the following embodiments, the technical scheme claimed in the present application can be implemented. The division of the following embodiments is for the convenience of description, and should not constitute any limitation on the specific implementation of the present invention. The various embodiments can be combined and referenced with each other without contradiction.
[0017] One embodiment of the present invention relates to a short-pitch winding motor, including a motor stator, a motor rotor, a motor shaft, a bearing, and a flat wire. Figure 1 As shown; the bearing is arranged on the motor shaft, and the motor rotor is connected to the motor stator through the bearing; the motor intermediate logarithm is P, the total number of slots is Z, the number of slots per pole per phase is Q, and the number of slot layers is X; wherein P is a positive number greater than or equal to 4, Z=Q*P*3, and X is an even number ≥2; the flat wire is arranged in a short-pitch winding manner, specifically including that two consecutive adjacent slot layers in an even number of slot layers are regarded as a slot layer group, and the first slot layer in each slot layer group is arranged on the second slot layer; in any slot layer group, the nth stator slot of the first slot layer is connected to the nth stator slot of ... The n+5th stator slot of the second slot layer is connected by a flat wire; between the slot layer groups, the nth stator slot of the second slot layer of the Mth slot layer group is connected to the n+7th stator slot of the first slot layer of the M+1th slot layer group by a flat wire; in the outermost slot layer, the m+1th stator slot on the right side of the lead-out stator slot m is connected to the m-6th stator slot on the left side of the lead-in stator slot m-5 by a flat wire; in the innermost slot layer, the flat wire is reversed after one turn of winding and reconnected to the innermost slot layer; wherein n, m, and M are all integers ≥1.
[0018] In one example, the parameters of the motor can be set as follows: the number of slots per pole per phase Q is 2, the number of level pairs P is 8, and the total number of slots is 48 and the number of slot layers X is 6 through Z=Q*P*3. Figure 2 As shown. The six slot layers are A, B, C, D, E, and F from the inside to the outside, AB is a slot layer group, CD is a slot layer group, and EF is a slot layer group. The specific winding method is as follows:
[0019] In any slot layer group, the nth stator slot of an adjacent slot layer is connected to the n+5th stator slot of another slot layer through a flat wire. For example, in the EF slot layer group, stator slot F7 is connected to stator slot E12. Here, stator slot F7 is the stator slot corresponding to the position of slot number 7 in the F layer, and stator slot F19 is connected to stator slot E24. In the other two slot layer groups AB and CD, the same connection method can be used to realize the connection winding inside the slot layer group. By setting the span between coils in any slot layer group to 5, the magnetic field distribution can be made more uniform and the harmonic components in the magnetic field can be reduced.
[0020] Between slot layer groups, the nth stator slot in the slot layer adjacent to the second slot layer group in the first slot layer group is connected to the n+7th stator slot in the slot layer adjacent to the first slot layer group in the second slot layer group through a flat wire. For example, between the EF slot layer group and the CD slot layer group, the stator slot E48 is connected to the stator slot D7, and the stator slot D13 is connected to the stator slot E6. Between the other two slot layer groups AB and CD, the same connection method can be used to achieve the connection winding between the slot layer groups. The coil span between the slot layer groups is set to 7, which occupies a shorter length. While achieving the mutual superposition of electromotive force, the resistance and inductance of this coil can be reduced, which helps to improve the efficiency of the motor.
[0021] In the outermost slot layer, the m+1 stator slot on the right side of the lead-out stator slot m is connected to the m-6 stator slot on the left side of the lead-in stator slot m-5 by a flat wire. For example, in this embodiment, Figure 2 As shown, m is 12, the outermost slot layer is F, wherein the leading stator slot is F7 and the leading stator slot is F12. In this case, the stator slot F13 is connected to the stator slot F6.
[0022] In the innermost slot layer, the flat wire after winding one turn is reversely twisted and reconnected to the innermost slot layer. For example, in this embodiment, Figure 2 As shown, the innermost slot layer is A, stator slot A48 is connected to stator slot A6, and stator slot A47 is connected to stator slot A5. By adopting a reverse twisting method, the number of bridge wires can be reduced, thereby reducing the weight and cost of the motor.
[0023] Specifically, in this embodiment, based on the above connection methods, the overall winding connection when there is only one branch includes:
[0024] F7-->E12-->F19-->E24-->F31-->E36-->F43-->E48-->D7-->C12-->D19-->C24-- >D31-->C36-->D43-->C48-->B7-->A12-->B19-->A24-->B31-->A36-->B43-->A48- ->A6-->B1-->A42-->B37-->A30-->B25-->A18-->B13-->C6-->D1-->C42-->D37--> C30-->D25-->C18-->D13-->E6-->F1-->E42-->F37-->E30-->F25-->E18-->F13--> F6-->E11-->F18-->E23-->F30-->E35-->F42-->E47-->D6-->C11-->D18-->C23--> D30-->C35-->D42-->C47-->B6-->A11-->B18-->A23-->B30-->A35-->B42-->A47-- >A5-->B48-->A41-->B36-->A29-->B24-->A17-->B12-->C5-->D48-->C41-->D36-- >C29-->D24-->C17-->D12-->E5-->F48-->E41-->F36-->E29-->F24-->E17-->F12.
[0025] In addition, since the motor winding is divided into multiple branches, the back electromotive force can be reduced, the voltage mutation at both ends of the motor can be reduced, and the overvoltage impact on electrical equipment can be reduced; during the operation of the motor, the heat loss and voltage drop generated by each branch current are independent of each other. Multiple parallel branches can reduce the operating current, reduce motor heating and reduce the load of heat dissipation equipment. The winding with only one branch can be divided into two or four parallel branch windings. The specific windings of the two parallel branches are as follows:
[0026] First branch
[0027] F7-->E12-->F19-->E24-->F31-->E36-->F43-->E48-->D7-->C12-->D19-->C24-- >D31-->C36-->D43-->C48-->B7-->A12-->B19-->A24-->B31-->A36-->B43-->A48 -->A6-->B1-->A42-->B37-->A30-->B25-->A18-->B13-->C6-->D1-->C42-->D37- ->C30-->D25-->C18-->D13-->E6-->F1-->E42-->F37-->E30-->F25-->E18-->F13
[0028] Second branch road
[0029] F6-->E11-->F18-->E23-->F30-->E35-->F42-->E47-->D6-->C11-->D18-->C23--> D30-->C35-->D42-->C47-->B6-->A11-->B18-->A23-->B30-->A35-->B42-->A47-- >A5-->B48-->A41-->B36-->A29-->B24-->A17-->B12-->C5-->D48-->C41-->D36-- >C29-->D24-->C17-->D12-->E5-->F48-->E41-->F36-->E29-->F24-->E17-->F12.
[0030] In one example, when the motor winding includes three-phase windings of U, V, and W, the U-phase winding is set as in the above embodiment; the V-phase winding is set in the same manner as the U-phase winding by increasing the number of slots by 4 in a clockwise direction following the U-phase winding; the W-phase winding is set in the same manner as the U-phase winding by increasing the number of slots by 4 in a clockwise direction following the V-phase winding. Specifically, the connection relationship diagram of the V-phase winding is as follows: Figure 3 As shown, the U-phase winding connection diagram is as follows Figure 4 The schematic diagram of the completed three-phase winding is as follows: Figure 5 As shown, each stator slot is numbered in the inner circle, and the numbers increase in a clockwise direction until the end of a circle.
[0031] In one example, the motor also includes a motor stator, a motor rotor, a motor shaft, a bearing and other components. The motor stator includes a stator silicon steel punching, an insulating paper, a bridge wire, and a three-phase line connection terminal. The flat wire is a flat wire winding copper wire with an insulating varnish. The stator silicon steel punching is made of 0.2-0.27mm silicon steel sheets stacked together, and the insulating paper is distributed in each slot to insulate between the phase and the ground. The flat wire winding copper wire with an insulating varnish is distributed in each slot and stacked in multiple layers. The bridge wire connects the three-phase branch and is connected to the three-phase line connection terminal.
[0032] Those skilled in the art will appreciate that the above-mentioned embodiments are specific examples for implementing the present invention, and in actual applications, various changes may be made thereto in form and detail without departing from the spirit and scope of the present invention.
Claims
1. A short-pitch winding motor, characterized in that: Including motor stator, motor rotor, motor shaft, bearings, flat wire; The bearing is arranged on the motor shaft, and the motor rotor is connected to the motor stator through the bearing; The number of intermediate pairs of the motor is P, the total number of slots is Z, the number of slots per pole per phase is Q, and the number of slot layers is X; wherein P is a positive number greater than or equal to 4, Z=Q*P*3, and X is an even number ≥2; The flat wire is arranged in a short-distance winding manner, specifically including: Two consecutive adjacent slot layers in the even number of slot layers are regarded as a slot layer group, and the first slot layer in each slot layer group is arranged on the second slot layer; In any slot layer group, the nth stator slot of the first slot layer is connected to the n+5th stator slot of the second slot layer by a flat wire; Between the slot layer groups, the nth stator slot of the second slot layer of the Mth slot layer group is connected to the n+7th stator slot of the first slot layer of the M+1th slot layer group via a flat wire; In the outermost slot layer, the m+1 stator slot on the right side of the exit stator slot m is connected to the m-6 stator slot on the left side of the entry stator slot m-5 by a flat wire; In the innermost slot layer, the flat wire after winding one turn is reversely twisted and reconnected to the innermost slot layer; Wherein, n, m, and M are all integers ≥1.
2. The short-pitch winding motor according to claim 1, characterized in that: The short-pitch winding motor is a three-phase motor, including three phases U, V, and W; The flat wire winding methods of the three phases U, V and W are all the short-distance winding methods; The V-phase flat wire winding is set in the same manner as the U-phase winding, with 4 slots added in the clockwise direction; The W-phase flat wire winding is arranged in a clockwise direction with 4 slots added in accordance with the V-phase winding.
3. The short-pitch winding motor according to claim 2, characterized in that: The motor stator comprises stator silicon steel punching sheets, insulating paper, bridge wires, and three-phase line connection terminals; The insulating paper is arranged in the stator slot of the silicon steel punching sheet; The bridge wire links the three-phase branches and is connected to the three-phase line connection terminals.
4. The short-pitch winding motor according to claim 3, characterized in that: The stator silicon steel punching sheets are formed by stacking silicon steel sheets with a thickness of 0.2-0.27 mm.
5. The short-pitch winding motor according to claim 3, characterized in that: The insulating paper is distributed in Z slots.