Flat wire motor winding
By employing irregularly shaped hairpin conductors and a multi-layer winding structure in the flat wire motor windings, the problem of difficult copper busbar connection welding was solved, enabling low-cost and efficient manufacturing and assembly, and improving motor performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- XUZHOU DONGXIN MICROELECTRONICS TECH CO LTD
- Filing Date
- 2025-04-23
- Publication Date
- 2026-05-26
AI Technical Summary
The copper busbar connection in existing flat wire motor windings presents challenges in welding and increases the amount of copper used, leading to higher manufacturing difficulty and increased costs.
By using irregularly shaped hairpin conductors and connecting them with multi-layer winding structure and irregularly shaped arrays, the N-pole and S-pole hairpin conductors are connected in series, simplifying the process and reducing resistance.
It reduces the difficulty and cost of coil manufacturing, improves product quality, and simplifies the manufacturing and assembly process.
Smart Images
Figure CN224289429U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of flat wire winding technology, specifically a flat wire motor winding. Background Technology
[0002] An electric motor (including electric motors and generators) is a device that converts electrical energy into mechanical energy (or mechanical energy into electrical energy) based on the principle of electromagnetic induction. An electric motor includes a stator and a rotor, with windings arranged in the slots 5 of the iron core.
[0003] With the expansion of the market and the pursuit of high-quality performance, the round enameled wire drive motors used in electric tricycles and electric motorcycles are gradually being replaced by flat wire motors. Electric tricycle and electric motorcycle drive motors generally use concentrated winding motors, which have very low magnetic reluctance torque and high back electromotive force. Under the same voltage platform, the motors have poor field weakening ability, low speed, and a narrow high-efficiency range. Meanwhile, electric tricycles and electric motorcycles require increasingly larger motor torque and higher speeds, making concentrated winding motors increasingly unable to meet market demands. Currently, with the rapid development of new energy vehicles, most of their drive motors use flat wire motors. The high slot fill factor of flat wire motors amplifies their advantages of miniaturization and low cost, leading to the near-complete replacement of round wire motors by new energy flat wire motors, which now dominate the market.
[0004] Copper busbars are often used to connect the two sets of hairpins in flat wire windings. However, the copper busbar connection process is relatively complicated, with difficulties in welding and a lot of trouble in insulation treatment at the welding points. It also increases the end height and the amount of copper used. Utility Model Content
[0005] To address the difficulties in welding copper busbar connections and the increased use of copper materials, the purpose of this invention is to provide a flat wire motor winding.
[0006] To solve the above-mentioned technical problems, this utility model adopts the following technical solution: a flat wire motor winding, comprising a stator core and a flat wire winding disposed on the stator core, the flat wire winding comprising: a plurality of hairpin conductors, the hairpin conductors being bent into a U-shape, each hairpin conductor comprising two parallel legs and a bend connecting the two legs, the stator core having core slots, the legs of the hairpin conductors being disposed within the core slots; the hairpin conductors employ a multi-layer winding structure, the number of layers per slot N ≥ 4 (N is an even number), defined as A, B, C, D from the inner layer to the outer layer, the inner layer hairpin and the outer layer... The span of each hairpin is Y-1, and they are divided into AB layer and CD layer hairpins, where Y is the winding pitch. The AB layer and CD layer hairpins are placed into the corresponding iron core slots from the inside to the outside. After all the hairpins are inserted into the iron core slots, the straight ends of the hairpin conductors are twisted outward to form two legs. The irregular hairpins are set on the outermost layer of the iron core slots. The N pole and S pole hairpin conductors are connected in series. By using irregularly shaped hairpins, the difficulty and cost of coil manufacturing are reduced, and the product quality is improved. The hairpin conductors have a short pitch structure. The short pitch can reduce resistance, improve motor performance, simplify the process, and facilitate manufacturing and assembly.
[0007] Preferably, the hairpin connection method follows the wave winding connection rule. All hairpins belonging to the same phase under the same polarity (N1, N2) are connected in series in a wave pattern to form a group by forward or reverse wave winding. Then, hairpins belonging to the same phase under the other polarity (S1, S2) are connected in series in a wave pattern to form another group.
[0008] Compared with the prior art, the beneficial effects of this utility model are as follows:
[0009] 1. By using irregularly shaped hairpins to connect the N and S poles in series end to end, when using wave windings in flat wire motors, irregularly shaped hairpins are used to reduce the difficulty and cost of coil manufacturing and improve product quality. The irregularly shaped hairpins are installed on the outermost layer of the stator, mainly to make room for them and prevent interference between the irregularly shaped hairpins. Attached Figure Description
[0010] To more clearly illustrate the technical solutions in the embodiments of this utility model 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 only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0011] Figure 1 The diagram shows the unfolded connection principle of the flat wire winding structure of this utility model.
[0012] Figure 2This is a schematic diagram of the stator core and flat wire winding structure of this utility model.
[0013] Figure 3 This is a schematic diagram of the stator core structure forming of this utility model.
[0014] Figure 4 This is a schematic diagram of the twisting of the irregular hair clip structure of this utility model.
[0015] In the diagram: 1. Hairpin conductor; 2. Stator core; 3. Bending head; 4. Irregular hairpin; 5. Core slot; 6. Support leg; 11. Inner hairpin; 12. Outer hairpin. Detailed Implementation
[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0017] Example: Figure 1-4 As shown, this utility model provides a flat wire motor winding, including a stator core 2 and a flat wire winding disposed on the stator core 2. The flat wire winding includes: a plurality of hairpin conductors 1, each hairpin conductor 1 being bent into a U-shape. Each hairpin conductor 1 includes two parallel legs 6 and a bending head 3 connecting the two legs 6. The bending head 3 is formed by twisting the ends of the legs 6 outward. The stator core 2 has core slots 5, and the legs 6 of the hairpin conductors 1 are disposed in the core slots 5. The hairpin conductors 1 adopt a multi-layer winding structure, with the number of layers N ≥ 4 (N is an even number) per slot. The layers are defined as A, B, C, and D from the inner layer to the outer layer. The span of both hairpin 11 and outer hairpin 12 is Y-1, and they are divided into AB layer and CD layer hairpins in sequence, where Y is the winding pitch. The AB layer and CD layer hairpins are placed into the corresponding iron core slots 5 from the inside to the outside. After all hairpins are inserted into the iron core slots 5, the straight ends of the hairpin conductors 1 are twisted outward to form two legs 6. The irregular hairpins 4 are set on the outermost layer of the iron core slots 5. The N pole and S pole hairpin conductors 1 are connected in series by the irregular hairpins 4. By using irregular arrangement, the difficulty and cost of coil manufacturing are reduced, and the product quality is improved. The hairpin conductors 1 have a short pitch structure. The short pitch can reduce the resistance and improve the motor performance, simplify the process and facilitate manufacturing and assembly.
[0018] The hairpin connection method of this utility model follows the wave winding connection law. By forward or reverse wave winding, all hairpins belonging to the same phase under the same polarity (N1, N2) are connected in series in a wave shape to form a group. Then, hairpins belonging to the same phase under the other polarity (S1, S2) are connected in series in a wave shape to form another group.
[0019] Stator flat wire windings are not limited to 48-slot 8-pole flat wire motors; they are also applicable to 72-slot 8-pole, 96-slot 8-pole, 54-slot 6-pole, and 72-slot 6-pole flat wire motors.
[0020] Working principle: Taking a 48-slot, 8-pole motor as an example, each slot winding has 4 conductors distributed in 4 layers. The hairpin conductor 1 is divided into inner hairpin 11AB and outer hairpin 12CD. The hairpin has a short pitch structure with a span of 5. After all the hairpins are inserted into the iron core slot 5, the straight ends of the hairpins are twisted outward to form two legs 6. The two legs 6A and 6B of the AB layer hairpins are connected to the legs 6B and 6A of the two AB layer hairpins on both sides of the stator circumference with a span of 7, respectively. When the AB layer is connected in series with a coil (wound around the stator once), the winding will return to the original slot and the leg 6B will be connected to the leg 6C of the CD layer. In this way, the AB and CD hairpins are connected in sequence. Then, the irregular hairpin 4 is inserted into the outermost layer of the iron core slot 5, and the N pole and S pole hairpins are connected in series end to end using an irregular arrangement. By using an irregular arrangement, the difficulty and cost of coil manufacturing are reduced, and the product quality is improved.
[0021] All standard parts used in this invention can be purchased from the market, and irregular parts can be customized according to the description and drawings. The specific connection methods of each part adopt conventional methods such as bolts, rivets, and welding that are mature in the prior art. The machinery, parts and equipment adopt conventional models in the prior art, and the circuit connection adopts conventional connection methods in the prior art, which will not be described in detail here.
[0022] Obviously, those skilled in the art can make various modifications and variations to this utility model without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this utility model and their equivalents, this utility model also intends to include these modifications and variations.
Claims
1. A flat wire motor winding, comprising a stator core (2) and a flat wire winding disposed on the stator core (2), characterized in that: The flat wire winding includes: Several hairpin conductors (1) are bent into a U-shaped structure. Each hairpin conductor (1) includes two parallel legs (6) and a bending head (3) connecting the two legs (6). The stator core (2) has a core groove (5), and the legs (6) of the hairpin conductor (1) are located in the core groove (5). The irregular hairpin (4) is located on the outermost layer of the iron core groove (5) and is used for the head and tail of the hairpin conductor (1) in series.
2. A flat wire motor winding as described in claim 1, characterized in that, The hairpin conductor (1) includes an inner hairpin (11) and an outer hairpin (12), which are placed into the corresponding iron core slots (5) from the inside to the outside.
3. A flat wire motor winding as described in claim 1, characterized in that, The bending head (3) is formed by twisting the end of the support leg (6) outward.
4. A flat wire motor winding as described in claim 1, characterized in that, The hairpin conductor (1) is in the form of a wave winding.
5. A flat wire motor winding as described in claim 1, characterized in that, The hairpin conductor (1) adopts a multi-layer winding structure, and the number of winding layers N in the iron core slot (5) is greater than or equal to (4).
6. A flat wire motor winding as described in claim 1, characterized in that, The hairpin conductor (1) has a short pitch structure.