Short-distance winding motor
By optimizing the magnetic field distribution through short-pitch winding and reverse twisting connection, the problems of high harmonic content and poor NVH performance of flat wire motors in new energy vehicles are solved, achieving low harmonic content and low-cost design of the motor.
Patent Information
- Application Number
- CN202520158246.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Priority Date
- 2024-12-05
- Filing Date
- 2025-01-23
- Publication Date
- 2026-01-09
- Estimated Expiration
- 2035-01-23
AI Technical Summary
The full-pitch windings of existing flat-wire motors for new energy vehicles result in high harmonic content and poor noise, vibration, and acoustic roughness performance, necessitating improvements in the motor's NVH performance.
By adopting a short-pitch winding method, the magnetic field distribution is optimized and high-order harmonics are reduced by changing the coil span. The number of bridging wires is reduced by using a reverse twisting connection method, and the windings are divided into multiple parallel branch windings.
It reduces the harmonic content of the motor, reduces cogging torque and back EMF harmonic distortion rate, improves the NVH performance of the motor, and reduces the weight and cost of the motor.
Smart Images
Figure CN223785832U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to a flat wire motor stator winding for new energy vehicles, and more particularly to a short-pitch winding motor. Background Technology
[0002] Currently, most flat-wire motors for new energy vehicles use full-pitch windings, which result in high harmonic content, large torque fluctuations, and poor noise, vibration, and harshness (NVH) performance.
[0003] Therefore, for motors with P-level logarithms, Z-slots, X-layer flat wire, and Q slots per pole per phase, a new short-pitch winding method is needed 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. Utility Model Content
[0004] The purpose of this invention is to provide a short-pitch winding motor to improve the motor's harmonic content, reduce motor cogging torque, load torque pulsation, and back EMF harmonic distortion rate, thereby improving the motor's NVH performance.
[0005] To solve the above-mentioned technical problems, the present invention provides a short-pitch winding motor, including a motor stator, a motor rotor, a motor shaft, bearings, and flat wires; the bearings are mounted on the motor shaft, and the motor rotor is connected to the motor stator through the bearings; the number of pole pairs in 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; where P is a positive number greater than or equal to 4, Z = Q * P * 3, and X is an even number ≥ 2; the flat wires are arranged in a short-pitch winding manner, specifically including that two consecutive adjacent slot layers in an even number of slot layers form a slot layer group, and the first slot layer in each slot layer group is set in a... On the second slot layer; in any slot layer group, the nth stator slot of the first slot layer and the (n+5th)th stator slot of the second slot layer are connected by a flat wire; between slot layer groups, the nth stator slot of the second slot layer of the Mth slot layer group and the (n+7th)th stator slot of the first slot layer of the (M+1th)th slot layer group are connected by a flat wire; in the outermost slot layer, the (m+1th)th stator slot to the right of the leading stator slot m and the (m-6th)th stator slot to the left of the leading stator slot m-5 are connected by a flat wire; in the innermost slot layer, the flat wire after one turn of winding is reverse-twisted and reconnected to the innermost slot layer; where n, m, and M are all integers ≥ 1.
[0006] In another example, the short-pitch winding motor is a three-phase motor, including three phases: U, V, and W. The flat wire winding method of the three phases U, V, and W are all the short-pitch winding method. The V phase flat wire winding is set to increase the number of slots by 4 in a clockwise direction in line 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 line with the V phase winding.
[0007] In another example, the motor stator includes stator silicon steel laminations, insulating paper, bridging wires, and three-phase connection terminals; the insulating paper is disposed in the stator slots of the silicon steel laminations; the bridging wires connect the three-phase branches and are connected to the three-phase connection terminals.
[0008] In another example, the stator silicon steel laminations are made of stacked silicon steel sheets with a thickness between 0.2 and 0.27 mm.
[0009] In another example, the insulating paper is distributed in Z slots.
[0010] Compared with existing technologies, this invention replaces the full-pitch winding method with a short-pitch winding. Because the short-pitch winding changes the coil span, it results in a more uniform magnetic field distribution and reduces harmonic components. Furthermore, the optimized magnetic field distribution of the short-pitch winding reduces the amplitude of harmonic potentials within the motor. Additionally, the short-pitch winding design effectively reduces the generation of higher-order harmonics, minimizing their impact on motor operation. Moreover, a reverse-twisting method is used to achieve connection between in-phase components, reducing the number of bridging wires and thus lowering motor weight and cost. Attached Figure Description
[0011] Figure 1 This is a schematic diagram of the motor connection structure according to one embodiment of the present invention;
[0012] Figure 2 This is a schematic diagram of the winding connection structure according to one embodiment of the present invention;
[0013] Figure 3 This is one embodiment of the present utility model. Figure 2 This is a schematic diagram of the V-phase winding connection structure for the U-phase.
[0014] Figure 4 This is one embodiment of the present utility model. Figure 2 This is a schematic diagram of the W-phase winding connection structure for the U-phase.
[0015] Figure 5 This is a schematic diagram of a three-phase motor winding according to one embodiment of the present invention. Detailed Implementation
[0016] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the various embodiments of this utility model will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been provided in the various embodiments of this utility model to facilitate a better understanding of this application. However, the technical solutions claimed in this application can be implemented even without these technical details and various changes and modifications based on the following embodiments. The division of the various embodiments below is for ease of description and should not constitute any limitation on the specific implementation of this utility model. The various embodiments can be combined with and referenced by each other without contradiction.
[0017] One embodiment of this utility model relates to a short-pitch winding motor, including a motor stator, a motor rotor, a motor shaft, bearings, and flat wire, specifically as follows: Figure 1 As shown; the bearing is mounted on the motor shaft, and the motor rotor is connected to the motor stator via the bearing; the number of intermediate pole pairs in 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; where 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 set by a short-pitch winding method, specifically including that two consecutive adjacent slot layers in an even number of slot layers form a slot layer group, and the first slot layer in each slot layer group is set 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 second slot layer. The (n+5)th stator slot of the second slot layer is connected by a flat wire; between slot layer groups, the nth stator slot of the second slot layer of the Mth slot layer group is connected to the (n+7)th stator slot of the first slot layer of the (M+1)th slot layer group by a flat wire; in the outermost slot layer, the (m+1)th stator slot to the right of the stator slot m is connected to the (m-6)th stator slot to the left of the stator slot m-5 by a flat wire; in the innermost slot layer, the flat wire after one turn of winding is reverse-twisted and reconnected to the innermost slot layer; where n, m, and M are all integers ≥ 1.
[0018] In one example, the motor parameters can be set as follows: the number of slots per pole per phase, Q, is 2; the number of stage pairs, P, is 8; and the total number of slots, Z = Q * P * 3, is 48, with X being 6 slot layers. In this embodiment, the specific winding diagram is as follows: Figure 2 As shown. The six slot layers, from the inside out, are A, B, C, D, E, and F. AB forms one slot layer group, CD forms another, and EF forms yet another. The specific winding configuration is as follows:
[0019] In any slot group, the nth stator slot of one adjacent slot group is connected to the (n+5)th stator slot of another slot group via a flat wire. For example, in slot group EF, stator slot F7 is connected to stator slot E12. Here, stator slot F7 corresponds to the 7th slot in slot F. Stator slot F19 is connected to stator slot E24. The same connection method can be used in the other two slot groups AB and CD to achieve the internal winding connections within the slot group. By setting the span between coils in any slot group to 5, the magnetic field distribution becomes more uniform, reducing harmonic components in the magnetic field.
[0020] Between slot groups, the nth stator slot in the slot layer adjacent to the second slot group in the first slot group is connected to the (n+7)th stator slot in the slot layer adjacent to the first slot group in the second slot group via a flat wire. For example, between slot groups EF and CD, stator slot E48 is connected to stator slot D7, and stator slot D13 is connected to stator slot E6. The same connection method can be used between the other two slot groups AB and CD to achieve interconnected windings. Setting the coil span to 7 between slot groups occupies a shorter length, which allows for the superposition of electromotive forces while reducing the resistance and inductance of the coil, thus improving motor efficiency.
[0021] In the outermost slot layer, the (m+1)th stator slot to the right of stator slot m is connected to the (m-6)th stator slot to the left of stator slot m-5 via a flat wire. For example, in this embodiment, as... Figure 2 As shown, m is 12, the outermost slot layer is F, where the introduced stator slot is F7 and the led-out stator slot is F12. In this case, stator slot F13 is connected to stator slot F6.
[0022] In the innermost slot layer, the flat wire, after one turn of winding, is reverse-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 bridging wires can be reduced, thereby reducing the weight and cost of the motor.
[0023] Specifically, in this embodiment, considering the above connection methods, the overall winding connection in the case of 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] Furthermore, dividing the motor windings into multiple branches reduces back electromotive force, lowers voltage spikes across the motor, and minimizes overvoltage surges to electrical equipment. During motor operation, the heat loss and voltage drop generated by each branch current are independent; multiple parallel branches reduce the operating current and the load on motor heating and cooling equipment. The aforementioned winding with only one branch can be divided into two or four parallel branch windings. The specific windings for two parallel branches are shown below:
[0026] First branch road
[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 windings include three-phase windings (U, V, and W), the U-phase winding is configured as described in the above embodiment; the V-phase winding increases by four slots clockwise from the U-phase winding, following the same configuration; the W-phase winding increases by four slots clockwise from the V-phase winding, following the same configuration. Specifically, the V-phase winding connection diagram is shown below. Figure 3 As shown in the diagram, the connection relationship of the U-phase winding is as follows: Figure 4 As shown in the diagram. A schematic diagram of the completed three-phase winding is shown below. Figure 5 As shown, the number of each stator slot is marked in the inner ring, and the number increases clockwise until the end of one ring.
[0031] In one example, the motor also includes components such as a stator, rotor, shaft, and bearings. The stator comprises stator silicon steel laminations, insulating paper, bridging wires, and three-phase connection terminals. The flat wires are copper wires wound with insulating enamel. The stator silicon steel laminations are made of stacked silicon steel sheets between 0.2-0.27mm in diameter. Insulating paper is distributed in each slot to provide insulation between phases and ground. The copper wires wound with insulating enamel are distributed in each slot and stacked in multiple layers. The bridging wires connect the three-phase branches and are connected to the three-phase connection terminals.
[0032] Those skilled in the art will understand that the above embodiments are specific examples of implementing the present invention, and in practical applications, various changes can be made to them 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, This includes the motor stator, motor rotor, motor shaft, bearings, and flat wire; The bearing is mounted on the motor shaft, and the motor rotor is connected to the motor stator via the bearing; The motor has P pole pairs, Z total slots, Q slots per pole per phase, and X slot layers; where 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 configured using a short-pitch winding method, specifically including... Two consecutive adjacent slots in an even number of slots form a slot group, and the first slot in each slot group is set on the second slot. In any slot layer group, the nth stator slot of the first slot layer and the (n+5)th stator slot of the second slot layer are connected by a flat wire; Between slot groups, the nth stator slot of the second slot of the Mth slot group is connected to the (n+7)th stator slot of the first slot of the (M+1)th slot group by a flat wire. In the outermost slot layer, the (m+1)th stator slot to the right of stator slot m is connected to the (m-6)th stator slot to the left of stator slot m-5 by a flat wire. In the innermost slot layer, the flat wire after one turn of winding is reverse twisted and reconnected to the innermost slot layer; Where 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, comprising U, V, and W phases. The flat wire winding methods for the U, V, and W phases are all the short-pitch winding methods; The V-phase flat wire winding is configured to increase the number of slots by 4 in a clockwise direction, following the U-phase winding. The W-phase flat wire winding is configured to increase the number of slots by 4 in a clockwise direction, following the same pattern as the V-phase winding.
3. The short-pitch winding motor according to claim 2, characterized in that, The motor stator includes stator silicon steel laminations, insulating paper, bridging wires, and three-phase wire connection terminals; The insulating paper is disposed in the stator slot of the silicon steel lamination; The bridge connection connects the three-phase branch circuit and is connected to the three-phase line connection terminal.
4. The short-pitch winding motor according to claim 3, characterized in that, The stator silicon steel laminations are made of stacked silicon steel sheets with a thickness between 0.2 and 0.27 mm.
5. The short-pitch winding motor according to claim 3, characterized in that, The insulating paper is distributed in Z slots.