Stator, flat wire motor, powertrain and vehicle

Abstract

The present application discloses a stator, a flat wire motor, a power train, and a vehicle. The stator includes a stator core having a plurality of stator slots uniformly arranged along its circumferential direction on an inner wall, and a stator winding. Each phase winding includes a plurality of parallel branch paths that are rotationally symmetric in the circumferential direction. Each parallel branch path includes a plurality of hairpin coils connected by connecting wires and having different pitches. N layers of hairpin coils are provided in any stator slot. The hairpin coils of each parallel branch path are provided across N slot layers in different stator slots. When N = (2n + 1) × 2, the combination of the total number of slot layers occupied by each parallel branch path in each stator slot is 2n, or 2n, 2n - 1, 2n - 2. When N = 2n × 2, the combination of the total number of slot layers occupied by each parallel branch path in each stator slot is 2n, 2n - 1, or 2n, 2n - 1, 2n - 2. When N = 2n + 1, the combination of the total number of slot layers occupied by each parallel branch path in each stator slot is n, n - 1, or n, n - 1, n - 2. By the above method, the stator according to the present application can avoid the generation of circulating current, reduce the manufacturing cost, and improve the efficiency of processing and manufacturing.

Description

Technical Field

[0001] This application relates to the technical field of flat wire motors, and particularly to stators, flat wire motors, power trains and vehicles.

Background Art

[0002] With the active promotion of the sales of new energy vehicles, new energy electric vehicles are becoming increasingly popular, and the market's requirements for the performance of the power system of electric vehicles are increasing. The main drive motor is the power output member of the power system and is one of the most important components of an electric vehicle. The requirements for the performance indicators of the main drive motor are also increasing. For example, high power density, torque density, small size and light weight are required. With the development of the flat wire process, the motors of electric vehicles are gradually using flat wire windings, and the flat wire windings can improve the occupation ratio of the stator slots and further improve the power density, efficiency and thermal conductivity of the motor.

[0003] Conventional motors mainly use wave windings or overlapping winding structures. By designing flat wire conductors in the winding structure in multiple layers, the AC resistance of the motor can be effectively reduced. However, with the increase in the number of layers of flat wire conductors, the wiring methods of the winding structure are not the same. Currently, multiple parallel branch paths are usually provided in the three-phase windings of the winding structure, and circulating currents are likely to occur between the branch paths. In addition, there are many wire types of hairpin coils, the production process is complex, and the manufacturing cost is high.

Summary of the Invention

Problems to be Solved by the Invention

[0004] Based on this, the present invention provides a stator, a flat wire motor, a power train and a vehicle.

Means for Solving the Problems

[0005] According to the first aspect, the present invention provides a stator core on its inner wall, in which a plurality of status rods are uniformly arranged along its circumferential direction, Including stator windings, The stator winding includes a three-phase winding, each phase winding includes a plurality of parallel branch lines, the plurality of parallel branch lines are rotationally symmetric in the circumferential direction, each parallel branch line is connected by connecting wires and includes a plurality of hairpin coils with different pitches, N layers of the hairpin coils are provided within each status lot, the hairpin coils of each parallel branch line are provided across N slot layers in different status lots, the three-phase winding is arranged sequentially and periodically along the circumferential direction of the stator core, and when N = (2n + 1) × 2, the number of slot layers occupied by each parallel branch line in each status lot The stator for a flat wire motor is provided, wherein the total number of combinations is 2n, or 2n, 2n-1, 2n-2, and when N=2n×2, the total number of combinations of slot layers occupied by each of the parallel branch lines in each of the status lots is 2n, 2n-1, or 2n, 2n-1, 2n-2, and when N=2n+1, the total number of combinations of slot layers occupied by each of the parallel branch lines in each of the status lots is n, n-1, or n, n-1, n-2, where N is a positive integer and 4 or greater, and the total number of slot layers in each of the status lots of each of the parallel branch lines is also a positive integer.

[0006] Furthermore, if each of the parallel branch paths occupies a total of 1 slot layer in the status lot, the location of the one slot layer is the 1st or Nth layer of the status lot. If each of the parallel branch paths occupies a total of 2 slot layers in the status lot, the two slot layers are located adjacent to each other in the status lot, or the two slot layers are the 1st and Nth layers of the status lot, respectively. If each of the parallel branch paths occupies a total of 3 slot layers in the status lot, two of the three slot layers are located adjacent to each other, and the location of the remaining slot layer is the 1st or Nth layer of the status lot, separated from the other two slot layers by four slot layers. If each of the parallel branch paths occupies a total of 4 slot layers in the status lot, the four slot layers are divided into two groups, each group is separated by four slot layers, and each group includes two adjacent slot layers.

[0007] Furthermore, each phase winding includes three parallel branch circuits.

[0008] Furthermore, the number of status lots is 54 or 72.

[0009] Furthermore, the combinations of hairpin coil pitches in each of the parallel branch lines are 8, 9, 11, 12, and 16.

[0010] Furthermore, the pitch of the hairpin coils in the same slot layer of each parallel branch is 9.

[0011] Furthermore, the pitch of the hairpin coils in the first slot layer or the Nth slot layer of each parallel branch is 8 or 8, 11.

[0012] Furthermore, each of the parallel branch lines has its entry end located in the Nth layer of the slot layer and its exit end located in the N-1th layer of the slot layer, or both the entry and exit ends of each of the parallel branch lines are located in the first and Nth slot layers, respectively.

[0013] Furthermore, the welding pitch between the hairpin coils in each of the parallel branch lines is either 9 or 11.

[0014] Furthermore, each of the parallel branch circuits includes a long-segment hairpin coil with a pitch of s / (2p)+a, a full-segment hairpin coil with a pitch of s / (2p), and a short-segment hairpin coil with a pitch of s / (2p)+a-4. s is the number of status lots, p is the number of parallel branch circuits, and a is an integer between 2 and 4.

[0015] Furthermore, in each of the parallel branch circuits, the first and second legs of the short-segment hairpin coils are located in the k-th slot layer and the k+1-th slot layer, respectively; the first and second legs of the long-segment hairpin coils are located in the k+1-th slot layer and the k+2-th slot layer, respectively; and the first and second legs of the full-segment hairpin coils are distributed in either the first slot layer or the n-th slot layer, where k is an odd number between 1 and n.

[0016] Furthermore, the number of slots per pole per phase of the flat wire motor is q, the voltage leads of the p parallel branch paths of each phase winding are located within s status lots and are located in the same slot layer or adjacent slot layer of different status lots, and the neutral point leads of the p parallel branch paths of each phase winding are located within s status lots and are located in the same slot layer or adjacent slot layer of different status lots.

[0017] Furthermore, both the voltage lead line and the neutral point lead line are located in the first slot layer or the nth slot layer.

[0018] Furthermore, the welding pitch between the hairpin coils in each of the parallel branch lines is s / (2p).

[0019] Furthermore, n is an even number, a=4, the short-section hairpin coil is the full-section hairpin coil, and in the phase band distribution of the three-phase windings, the polarity distribution of each odd-numbered layer is the same, the polarity distribution of each even-numbered layer is the same, and is shifted by one status lot relative to the polarity distribution of the odd-numbered layers.

[0020] Furthermore, the number of slot layers in the status lot is one of 4, 6, 8, and 10, the combination of hairpin coil pitches in each parallel branch is 10, 12, and 14, and the welding pitch between the hairpin coils in each parallel branch is 13.

[0021] Furthermore, each hairpin coil includes a first leg, a second leg, a connecting segment, a first bent segment, and a second bent segment, wherein the first and second legs are arranged in parallel and inserted into slot layers of different status lots, the connecting segment is connected to one end of the first and second legs, the first bent segment is connected to the other end of the first leg, the second bent segment is connected to the other end of the second leg, and both the first and second bent segments have welded ends.

[0022] Furthermore, the bending directions of the first bending segment and the second bending segment are the same and parallel, or they are arranged symmetrically.

[0023] According to a second aspect, the present invention provides a flat wire motor comprising a rotor and any of the above-described stators, wherein the rotor is provided in a space surrounded by the inner wall of the stator core.

[0024] According to a third aspect, the present invention includes a reduction gear and a flat wire motor as described above, wherein the flat wire motor provides a powertrain that is driven to the reduction gear.

[0025] According to the fourth aspect, the present invention provides a vehicle including the power train as described above.

Advantages of the Invention

[0026] The beneficial effects of the present application are as follows. Different from the prior art, the present application discloses a stator, a flat wire motor, a power train and a vehicle. The plurality of parallel branch paths of each phase winding are rotationally symmetric in the circumferential direction. Thus, the magnetic field distributions of the plurality of parallel branch paths in each phase winding are the same, and the potentials are balanced, so as to avoid the circulating current generated between the parallel branch paths, greatly reduce the additional AC copper loss at high frequencies, improve the efficiency of the flat wire motor during high-speed operation, avoid local overheating of the winding, extend the service life of the flat wire motor, and further, the hairpin coils of each parallel branch path are provided across N slot layers in different stator slots. Thereby, the potential phase difference due to the positions in the stator slots of the plurality of parallel branch paths of each phase winding can be eliminated. By limiting the number of slot layers N in the stator slots and the total number of slot layers occupied by the corresponding parallel branch paths in each stator slot, the wire type of the hairpin coils can be reduced, the manufacturing molds of the flat wire motor can be reduced, the manufacturing cost can be reduced, and the processing and manufacturing efficiency can be effectively improved. [[ID=​​​​​​​​​​​​​​​​​​​​Figure 1 is a schematic diagram of a circuit in which the parallel branch paths in each phase winding of the stator use triangular connections. [Figure 7] Figure 2 is a schematic diagram of the slot layer structure of the status lot in the stator core. [Figure 8] This is a schematic diagram of the first type of winding for the U-phase winding in the 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 4. [Figure 9] This is a schematic diagram of the second type of winding for the U-phase winding in the 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 4. [Figure 10] This is a schematic diagram of the winding of the U-phase winding in the 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 5. [Figure 11] This is a schematic diagram of the first type of winding for the U-phase winding in the 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 6. [Figure 12] This is a schematic diagram of the second type of winding for the U-phase winding in the 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 6. [Figure 13] This is a schematic diagram of the winding of the U-phase winding in the 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 7. [Figure 14] This is a schematic diagram of the winding of the U-phase winding in the 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 8. [Figure 15] This is a schematic diagram of the winding of the U-phase winding in the 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 9. [Figure 16] This is a schematic diagram of the winding of the U-phase winding in the 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 10. [Figure 17] This is a schematic diagram of the winding of the first parallel branch of the U-phase winding in a 6-pole, 72-slot flat wire motor according to the present invention, where the number of slot layers is 4 and a is 3. [Figure 18]Figure 17 is a schematic diagram of the winding of the second parallel branch of the U-phase winding in the flat wire motor shown. [Figure 19] Figure 17 is a schematic diagram of the winding of the third parallel branch of the U-phase winding in the flat wire motor shown. [Figure 20] This is a schematic diagram of the winding of the first parallel branch of the U-phase winding in a 6-pole, 72-slot flat wire motor according to the present invention, where the number of slot layers is 6 and a is 3. [Figure 21] Figure 20 is a schematic diagram of the winding of the second parallel branch of the U-phase winding in the flat wire motor shown. [Figure 22] Figure 20 is a schematic diagram of the winding of the third parallel branch of the U-phase winding in the flat wire motor shown. [Figure 23] This is a schematic diagram of the winding of the first parallel branch of the U-phase winding in a 6-pole, 72-slot flat wire motor according to the present invention, where the number of slot layers is 8 and a is 3. [Figure 24] Figure 23 is a schematic diagram of the winding of the second parallel branch of the U-phase winding in the flat wire motor shown. [Figure 25] Figure 23 is a schematic diagram of the winding of the third parallel branch of the U-phase winding in the flat wire motor shown. [Figure 26] This is a phase band distribution diagram for a 6-pole, 72-slot flat wire motor according to the present invention, where the number of slot layers is 4 and a is 4. [Figure 27] Figure 26 is a schematic diagram of the winding of the first parallel branch of the U-phase winding in the flat wire motor shown. [Figure 28] Figure 26 is a schematic diagram of the winding of the second parallel branch of the U-phase winding in the flat wire motor shown. [Figure 29] Figure 26 is a schematic diagram of the winding of the third parallel branch of the U-phase winding in the flat wire motor shown. [Figure 30] This is a schematic diagram of the winding of the first parallel branch of the U-phase winding in a 6-pole, 72-slot flat wire motor according to the present invention, where the number of slot layers is 6 and a is 4. [Figure 31]Figure 30 is a schematic diagram of the winding of the second parallel branch of the U-phase winding in the flat wire motor shown. [Figure 32] Figure 30 is a schematic diagram of the winding of the third parallel branch of the U-phase winding in the flat wire motor shown. [Figure 33] This is a schematic diagram of the winding of the first parallel branch of the U-phase winding in a 6-pole, 72-slot flat wire motor according to the present invention, where the number of slot layers is 4 and a is 2. [Figure 34] Figure 33 is a schematic diagram of the winding of the second parallel branch of the U-phase winding in the flat wire motor shown. [Figure 35] Figure 33 is a schematic diagram of the winding of the third parallel branch of the U-phase winding in the flat wire motor shown. [Figure 36] This is a schematic diagram of the winding of the first parallel branch of the U-phase winding in a 6-pole, 72-slot flat wire motor according to the present invention, where the number of slot layers is 6 and a is 2. [Figure 37] Figure 36 is a schematic diagram of the winding of the second parallel branch of the U-phase winding in the flat wire motor shown. [Figure 38] Figure 36 is a schematic diagram of the winding of the third parallel branch of the U-phase winding in the flat wire motor shown. [Modes for carrying out the invention]

[0028] The following describes the technical solutions in the embodiments of the present application clearly and completely with reference to the drawings of the embodiments, and it is clear that the embodiments described are some, but not all, embodiments of the present application. All other embodiments that a person skilled in the art could obtain without creative work based on the embodiments of the present application are all within the scope of protection of the present application.

[0029] In the embodiments of this Application, the terms “first,” “second,” and “third” are used solely for descriptive purposes and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features shown. Thus, features limited to “first,” “second,” and “third” may explicitly or implicitly include at least one such feature. In the description of this Application, unless otherwise clearly and specifically limited, “multiple” means at least two, e.g., two, three, etc. Also, the terms “include,” “have,” and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus comprising a series of steps or units is not limited to the steps or units shown, and may preferably further include steps or units not shown, or may preferably further include other steps or units specific to these processes, methods, products, or apparatus.

[0030] In this specification, “Examples” means that certain features, structures, or properties described in relation to an Example may be included in at least one Example of the Application. The use of this term in various places in this specification does not necessarily refer to the same Example, nor are they mutually exclusive or alternative to other Examples. Those skilled in the art will understand, both expressly and implicitly, that the Examples described herein may be combined with other Examples.

[0031] To facilitate understanding, the following explanations are provided for the technical terms used in this application.

[0032] The stator refers to the stationary part of a motor, and its function is to generate a rotating magnetic field.

[0033] A rotor refers to a rotating component in a motor, and its purpose is to convert electrical energy into mechanical energy.

[0034] Pitch refers to the distance that two identical element edges in a motor winding straddle the armature surface, and is usually expressed by the number of stator lots formed on the stator core.

[0035] As shown in Figures 1 and 2, Figure 1 is a schematic diagram of the structure of one embodiment of a stator of a flat wire motor according to the present application, and Figure 2 is a schematic diagram of the structure of the stator core in the stator shown in Figure 1. In one aspect of the present application, a flat wire motor is provided that includes a rotor and a stator, wherein the rotor is provided in a space surrounded by the inner wall of the stator core of the stator, the number of slots per pole per phase of the flat wire motor may be 3, the number of poles of the rotor may be even, and the combination of slot poles of the flat wire motor may be 6 poles 54 slots, 8 poles 72 slots, 10 poles 90 slots, 12 poles 108 slots, etc., and the present application is not specifically limited thereto.

[0036] As shown in Figure 1, the stator of the flat wire motor includes a stator core 10 and stator windings 20.

[0037] As shown in Figure 2, multiple status rods 11 are uniformly arranged along the circumferential direction on the inner wall of the stator core 10, and the number of status rods 11 is a multiple of 3, for example, the number of status rods 11 may be 54 or 72, and any status rod 11 extends in the axial direction of the stator core 10 and penetrates the inner wall of the stator core 10 along the axial direction of the stator core 10, and the status rods 11 are further divided into N layers along the radial direction of the stator core 10.

[0038] The stator winding 20 includes three phase windings arranged sequentially and periodically along the circumferential direction of the stator core 10, the three phase windings being a U-phase winding, a V-phase winding, and a W-phase winding, respectively. Each phase winding includes a plurality of parallel branch lines (hereinafter referred to as p parallel branch lines), and the plurality of parallel branch lines are rotationally symmetric in the circumferential direction. For example, each phase winding includes three parallel branch lines, and these three parallel branch lines are rotationally symmetric in the circumferential direction of the stator core 10, or each phase winding may include two or four parallel branch lines.

[0039] By limiting the multiple parallel branch lines in each phase winding to rotational symmetry in the circumferential direction, the magnetic field distribution of the multiple parallel branch lines in each phase winding becomes the same, and the potential is balanced. This avoids circulating currents generated between the parallel branch lines, significantly reduces additional AC copper losses at high frequencies, improves the efficiency of the flat wire motor during high-speed operation, avoids localized overheating of the windings, and extends the service life of the flat wire motor.

[0040] In this embodiment, the stator consists of three phase windings with a phase difference of 120 degrees electrical angle, and a stator core 10. The structure of the stator windings 20 is located on the stator core 10, and each phase winding includes three parallel branch paths. The three parallel branch paths rotate around the central axis of the stator core 10, and the three parallel branch paths in the same phase winding are rotationally symmetric. When the stator is applied to a flat wire motor, the central axis may refer to the rotor centerline of the rotor in the flat wire motor. The rotational symmetry may occur when a parallel branch path in the same phase winding moves by a certain number of stator rods before overlapping with another parallel branch path in the same phase winding.

[0041] As shown in Figure 5, Figure 5 is a schematic diagram of a circuit in which the parallel branch paths in each phase winding of the stator shown in Figure 1 use a star connection, and each phase winding consists of three parallel branch paths.

[0042] Optionally, as shown in Figure 6, Figure 6 is a schematic diagram of a circuit in which the parallel branch paths in each phase winding of the stator shown in Figure 1 use triangular connections, and each phase winding consists of three parallel branch paths.

[0043] As shown in Figures 1, 2, and 3, Figure 3 is a schematic diagram of the hairpin coil structure in the stator shown in Figure 1.

[0044] Each parallel branch line is connected by connecting wires and includes multiple hairpin coils 21 with different pitches. Each status lot 11 is provided with n layers of flat wire conductors of hairpin coils 21, where n is a positive integer, meaning that each slot layer in the status lot 11 is provided with a flat wire conductor. The hairpin coils 21 are formed of flat wire conductors, and the cross-section of the flat wire conductors is rectangular. They are inserted into the status lot 11. Each hairpin coil 21 includes two parallel straight segments 211 and a connecting segment 212 connecting the two straight segments 211, the straight segments 211 being inserted into the status rods 11 and the connecting segment 212 being located outside the status rods 11, the connecting segment 212 being U-shaped or V-shaped, the pitch of the hairpin coil being the number of status rods that the two parallel straight segments 211 of the hairpin coil 21 span, and the welding pitch between the hairpin coils 21 being the number of status rods that the adjacent straight segments 211 of two adjacent hairpin coils 21 span.

[0045] The hairpin coil 21 further includes a bent segment 213 connected to a straight segment 211, the bent segment 213 also located outside the stator rod 11 and, together with the connecting segment 212, is provided on the end face of the stator core 10, and adjacent bent segments 213 of adjacent hairpin coils in the same parallel branch are connected and electrically connected by connecting wires.

[0046] In one embodiment, after inserting the hairpin coil 21 into the status rod 11, the hairpin coil 21 is bent. Two folded segments 213After the hairpin coil 21 is inserted into the stator rod 11, its connecting segment 212 forms the wire insertion end of the stator winding 20. Folded segment 213 This forms the welded end of the stator winding 20.

[0047] Here, the bending direction of the hairpin coil may be set so that it bends to one side, and in other embodiments, as shown in Figure 4, The two folded segments 213 include a first folded segment 214 and a second folded segment 215. The bending directions of the first bent segment 214 and the second bent segment 215 of some of the hairpin coils 21 are parallel and used for winding with a change of direction, while the bending directions of the first bent segment 214 and the second bent segment 215 of the remaining hairpin coils 21 are symmetrically arranged and used for winding in the same direction, as shown in Figure 3.

[0048] In this invention, N layers of hairpin coils 21 are provided within each status lot 11, that is, each slot layer of the status lot 11 is provided with two linear segments 211 of one hairpin coil 21, and the hairpin coils 21 of each parallel branch are provided across N slot layers in different status lots 11, thereby eliminating the potential phase difference due to the position in the status lot of the multiple parallel branch lines of each phase winding, where N is a positive integer of 4 or more, for example, N may be 4, 5, 6, 7, 8, 9 or 10. For example, when N is 4, 4 layers of linear segments 211 are provided within each status lot 11.

[0049] Multiple parallel branch lines of the same phase are provided across n slot layers in different status lots, and the status lot 11 occupied by each phase winding is rotationally symmetrical around the stator circumference. As a result, the p branch lines of the same phase are perfectly symmetrical, preventing circulating current from being generated when the flat wire motor is operating normally, reducing copper losses in the motor, and improving motor efficiency.

[0050] As shown in Figure 7, Figure 7 is a schematic diagram of the slot layer structure of the status lot in the stator core shown in Figure 2, where in one specific application scenario, N is 6, and within each status lot 11 there are 6 linear segments 211, that is, within each status lot 11 there are 6 The array includes flat wire conductors, with the first layer designated L1, the second L2, the third L3, the fourth L4, the fifth L5, and the sixth L6. The first slot layer is the slot bottom layer of status lot 11, and the sixth slot layer is the slot opening layer, or alternatively, the first slot layer is the slot opening layer of status lot 11, and the sixth slot layer is the slot bottom layer.

[0051] In one embodiment, since the hairpin coils 21 within the same status lot 11 are in phase, interphase insulating paper is not required between the straight segments 211 of different layers within the same status lot 11, thereby reducing the insulation cost of the flat wire motor.

[0052] Here, when N=(2n+1)×2, the combination of the total number of slot layers occupied by each parallel branch in each status lot 11 is 2n, or 2n, 2n-1, 2n-2; when N=2n×2, the combination of the total number of slot layers occupied by each parallel branch in each status lot 11 is 2n, 2n-1, or 2n, 2n-1, 2n-2; and when N=2n+1, the combination of the total number of slot layers occupied by each parallel branch in each status lot 11 is n, n-1, or n, n-1, n-2, where N is a positive integer and 4 or greater, and the total number of slot layers in each status lot 11 of each parallel branch is also a positive integer.

[0053] For example, in the above application scenario, if the number of slot layers N of status lot 11 is 4, the combination of the total number of slot layers occupied by each parallel branch in each status lot 11 may be 2 or 1; if the number of slot layers N of status lot 11 is 6, the combination of the total number of slot layers occupied by each parallel branch in each status lot 11 may be 2 or 2, 1; and if the number of slot layers N of status lot 11 is 7, the combination of the total number of slot layers occupied by each parallel branch in each status lot 11 may be 3, 2 or 3, 2, 1.

[0054] By limiting the number of slot layers N in the status lot 11 and the total number of slot layers occupied by each corresponding parallel branch in each status lot, the wire type of the hairpin coil 21 can be reduced, the number of manufacturing molds for the flat wire motor can be reduced, manufacturing costs can be lowered, and the efficiency of processing and manufacturing can be effectively improved.

[0055] If each parallel branch has a total of 1 slot layer in status lot 11, the location of that one slot layer is the 1st or Nth layer of status lot 11; if each parallel branch has a total of 2 slot layers in status lot 11, the two slot layers are located adjacent to each other in status lot 11, or the two slot layers are the 1st and Nth layers of status lot 11, respectively; if each parallel branch has a total of 3 slot layers in status lot 11, two of the three slot layers are located adjacent to each other, and the location of the remaining slot layer is the 1st or Nth layer of status lot 11, separated from the other two slot layers by four slot layers; if each parallel branch has a total of 4 slot layers in status lot 11, the four slot layers are divided into two groups, each group is separated by four slot layers, and each group includes two adjacent slot layers. By such limited means, the wire type of the hairpin coil 21 can be further reduced, that is, the number of manufacturing molds can be further reduced, costs can be lowered, and the efficiency of processing and manufacturing can be improved.

[0056] In one embodiment, the combinations of hairpin coil pitches 21 in each parallel branch are 8, 9, 11, 12, and 16. In another embodiment, the pitch of the hairpin coil 21 in the same slot layer of each parallel branch is 9. In yet another embodiment, the pitch of the hairpin coil 21 in the first or nth slot layer of each parallel branch is 8 or 8 and 11. Here, the pitch of the hairpin coil 21 is the number of status lots that the two linear segments 211 of the hairpin coil 21 span.

[0057] Here, the welding pitch between the hairpin coils 21 in each parallel branch may be 9 or 11, that is, the number of status lots that two adjacent straight segments 211 of two adjacent hairpin coils 21 in the same parallel branch span is either 9 or 11.

[0058] In some embodiments, the entry end of each parallel branch is located in the Nth slot layer of the status lot 11, and the exit end is located in the N-1 slot layer of the status lot 11, or both the entry and exit ends of each parallel branch are located in the first and Nth slot layers of the status lot 11, thereby facilitating the drawing out of the entry and exit ends of the parallel branch. By concentrating the lead wire positions of the parallel branch, the axial and radial space required for the windings can be reduced, thereby lowering the manufacturing difficulty of the flat wire motor.

[0059] To facilitate understanding, the connection method for parallel branch lines in this application will be explained in detail below, referring to specific application scenarios.

[0060] In one specific application scenario, a 6-pole, 54-slot flat wire motor is used as an example. The number of status lots 11 in the stator core 10 is 54, the number of poles in the rotor is 6, the number of slots per pole per phase is 3, and the number of slot layers N in each status lot 11 is 4. The stator windings are divided into U-phase, V-phase, and W-phase, and the number of parallel branch circuits provided in each phase winding is 3.

[0061] As shown in Figure 8, Figure 8 is a schematic diagram of the first type of winding of the U-phase winding in a 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 4, and Figure 9 is a schematic diagram of the second type of winding of the U-phase winding in a 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 4. The solid lines indicate the connection method of the wire insertion end, the dashed lines indicate the connection method of the welded end, U1, U2, and U3 may be either voltage lead lines or neutral point lead lines, and X1, X2, and X3 may be either voltage lead lines or neutral point lead lines.

[0062] The first parallel branch, second parallel branch, and third parallel branch of the U-phase winding in this embodiment will be described in detail below, as shown in Figures 8 and 9.

[0063] Here, i(j) represents the j-th slot layer of the i-th slot; for example, 1(1) represents the first slot layer of the first slot, and 10(2) represents the second slot layer of the tenth slot.

[0064] There are two types of winding methods for the first parallel branch, second parallel branch, and third parallel branch of the U-phase winding in question.

[0065] As shown in Figure 8, in the first winding method, the slot numbers through which the series connection of the first parallel branch of the U-phase winding passes are 1(1)→10(2)→21(1)→30(2)→38(1)→47(2)→2(3)→11(4)→19(3)→28(4)→39(3)→48(4)→2(4)→47(3)→39(4)→30(3)→19(4)→10(3)→1(2)→46(1)→38(2)→29(1)→21(2)→12(1).

[0066] The slot numbers through which the series connection of the second parallel branch circuit of the U-phase winding passes are 2(1)→11(2)→19(1)→28(2)→39(1)→48(2)→3(3)→12(4)→20(3)→29(4)→37(3)→46(4)→3(4)→48(3)→37(4)→28(3)→20(4)→11(3)→2(2)→47(1)→39(2)→30(1)→19(2)→10(1).

[0067] The slot numbers through which the series connection of the third parallel branch of the U-phase winding passes are 3(1)→12(2)→20(1)→29(2)→37(1)→46(2)→1(3)→10(4)→21(3)→30(4)→38(3)→47(4)→1(4)→46(3)→38(4)→29(3)→21(4)→12(3)→3(2)→48(1)→37(2)→28(1)→20(2)→11(1).

[0068] As shown in Figure 9, in the second winding method, the slot numbers through which the series connection of the first parallel branch of the U-phase winding passes are 1(1)→10(2)→19(3)→28(4)→39(3)→48(4)→2(3)→11(4)→2(4)→47(3)→39(4)→30(3)→19(4)→10(3)→1(2)→46(1)→38(2)→29(1)→21(2)→12(1)→21(1)→30(2)→38(1)→47(2).

[0069] The slot numbers through which the series connection of the second parallel branch circuit of the U-phase winding passes are 2(1)→11(2)→20(3)→29(4)→37(3)→46(4)→3(3)→12(4)→3(4)→48(3)→37(4)→28(3)→20(4)→11(3)→2(2)→47(1)→39(2)→30(1)→19(2)→10(1)→19(1)→28(2)→39(1)→48(2).

[0070] The slot numbers through which the series connection of the third parallel branch circuit of the U-phase winding passes are 3(1)→12(2)→21(3)→30(4)→38(3)→47(4)→1(3)→10(4)→1(4)→46(3)→38(4)→29(3)→21(4)→12(3)→3(2)→48(1)→37(2)→28(1)→20(2)→11(1)→20(1)→29(2)→37(1)→46(2).

[0071] The U-phase winding, V-phase winding, and W-phase winding are uniformly and symmetrically distributed on the circumference of the stator core 10. The winding method for the V-phase and W-phase windings is omitted here.

[0072] In another application scenario, we still use a 6-pole, 54-slot flat wire motor as an example, where the number of status lots 11 in the stator core 10 is 54, the number of poles in the rotor is 6, the number of slots per pole per phase is 3, and the number of slot layers N in each status lot 11 is 5. The stator windings are divided into U-phase, V-phase, and W-phase, and the number of parallel branch circuits provided in each phase winding is 3.

[0073] As shown in Figure 10, Figure 10 is a schematic diagram of the winding of the U-phase winding in a 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 5.

[0074] As shown in Figure 10, the slot numbers through which the series connection of the first parallel branch of the U-phase winding passes are 1(1)→10(2)→21(1)→30(2)→38(1)→47(2)→2(3)→11(4)→19(3)→28(4)→39(3)→48(4)→3(5)→48(5)→37(5)→28(5)→20(5)→11(5)→2(4)→47(3)→39(4)→30(3)→19(4)→10(3)→1(2)→46(1)→38(2)→29(1)→21(2)→12(1).

[0075] The slot numbers through which the series connection of the second parallel branch circuit of the U-phase winding passes are 2(1)→11(2)→19(1)→28(2)→39(1)→48(2)→3(3)→12(4)→20(3)→29(4)→37(3)→46(4)→1(5)→46(5)→38(5)→29(5)→21(5)→12(5)→3(4)→48(3)→37(4)→28(3)→20(4)→11(3)→2(2)→47(1)→39(2)→30(1)→19(2)→10(1).

[0076] The slot numbers through which the series connection of the third parallel branch circuit of the U-phase winding passes are 3(1)→12(2)→20(1)→29(2)→37(1)→46(2)→1(3)→10(4)→21(3)→30(4)→38(3)→47(4)→2(5)→47(5)→39(5)→30(5)→19(5)→10(5)→1(4)→46(3)→38(4)→29(3)→21(4)→12(3)→3(2)→48(1)→37(2)→28(1)→20(2)→11(1).

[0077] In another application scenario, we still use a 6-pole, 54-slot flat wire motor as an example, where the number of status lots 11 in the stator core 10 is 54, the number of poles in the rotor is 6, the number of slots per pole per phase is 3, and the number of slot layers N in each status lot 11 is 6. The stator windings are divided into U-phase, V-phase, and W-phase, and the number of parallel branch circuits provided in each phase winding is 3.

[0078] There are two types of winding methods for the first parallel branch, second parallel branch, and third parallel branch of the U-phase winding. As shown in Figures 11 and 12, Figure 11 is a schematic diagram of the first type of winding for the U-phase winding in a 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 6, and Figure 12 is a schematic diagram of the second type of winding for the U-phase winding in a 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 6.

[0079] As shown in Figure 11, in the first winding method, the slot numbers through which the series connection of the first parallel branch of the U-phase winding passes are 1(1)→10(2)→21(1)→30(2)→38(1)→47(2)→2(3)→11(4)→19(3)→28(4)→39(3)→48(4)→3(5)→12(6)→20(5)→29(6)→37(5)→46(6)→3(6)→48(5)→37(6)→28(5)→20(6)→11(5)→2(4)→47(3)→39(4)→30(3)→19(4)→10(3)→1(2)→46(1)→38(2)→29(1)→21(2)→12(1).

[0080] The slot numbers through which the series connection of the second parallel branch circuit of the U-phase winding passes are 2(1)→11(2)→19(1)→28(2)→39(1)→48(2)→3(3)→12(4)→20(3)→29(4)→37(3)→46(4)→1(5)→10(6)→21(5)→30(6)→38(5)→47(6)→1(6)→46(5)→38(6)→29(5)→21(6)→12(5)→3(4)→48(3)→37(4)→28(3)→20(4)→11(3)→2(2)→47(1)→39(2)→30(1)→19(2)→10(1).

[0081] The slot numbers through which the series connection of the third parallel branch circuit of the U-phase winding passes are 3(1)→12(2)→20(1)→29(2)→37(1)→46(2)→1(3)→10(4)→21(3)→30(4)→38(3)→47(4)→2(5)→11(6)→19(5)→28(6)→39(5)→48(6)→2(6)→47(5)→39(6)→30(5)→19(6)→10(5)→1(4)→46(3)→38(4)→29(3)→21(4)→12(3)→3(2)→48(1)→37(2)→28(1)→20(2)→11(1).

[0082] Figure 1 2 As shown, in the second winding method, the slot numbers through which the series connection of the first parallel branch of the U-phase winding passes are 1(1)→10(2)→19(3)→28(4)→39(3)→48(4)→2(3)→11(4)→20(5)→29(6)→37(5)→46(6)→3(5)→12(6)→3(6)→48(5)→37(6)→28(5)→20(6)→11(5)→2(4)→47(3)→39(4)→30(3)→19(4)→10(3)→1(2)→46(1)→38(2)→29(1)→21(2)→12(1)→21(1)→30(2)→38(1)→47(2).

[0083] The slot numbers through which the series connection of the second parallel branch circuit of the U-phase winding passes are 2(1)→11(2)→20(3)→29(4)→37(3)→46(4)→3(3)→12(4)→21(5)→30(6)→38(5)→47(6)→1(5)→10(6)→1(6)→46(5)→38(6)→29(5)→21(6)→12(5)→3(4)→48(3)→37(4)→28(3)→20(4)→11(3)→2(2)→47(1)→39(2)→30(1)→19(2)→10(1)→19(1)→28(2)→39(1)→48(2).

[0084] The slot numbers through which the series connection of the third parallel branch of the U-phase winding passes are 3(1)→12(2)→21(3)→30(4)→38(3)→47(4)→1(3)→10(4)→19(5)→28(6)→39(5)→48(6)→2(5)→11(6)→2(6)→47(5)→39(6)→30(5)→19(6)→10(5)→1(4)→46(3)→38(4)→29(3)→21(4)→12(3)→3(2)→48(1)→37(2)→28(1)→20(2)→11(1)→20(1)→29(2)→37(1)→46(2).

[0085] In another application scenario, we still use a 6-pole, 54-slot flat wire motor as an example, where the number of status lots 11 in the stator core 10 is 54, the number of poles in the rotor is 6, the number of slots per pole per phase is 3, and the number of slot layers N in each status lot 11 is 7. The stator windings are divided into U-phase, V-phase, and W-phase, and the number of parallel branch circuits provided in each phase winding is 3.

[0086] As shown in Figure 13, Figure 13 is a schematic diagram of the winding of the U-phase winding in a 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 7.

[0087] As shown in Figure 13, the slot numbers through which the series connection of the first parallel branch of the U-phase winding passes are: 1(1)→10(2)→21(1)→30(2)→38(1)→47(2)→2(3)→11(4)→19(3)→28(4)→39(3)→48(4)→3(5)→12(6)→20(5)→29(6)→37(5)→46(6) →1(7)→46(7)→38(7)→29(7)→21(7)→12(7)→3(6)→48(5)→37(6)→28(5)→20(6)→11(5)→2(4)→47(3)→39(4)→30(3)→19(4)→10(3)→1(2)→46(1)→38(2)→29(1)→21(2)→12(1).

[0088] The slot numbers through which the series connection of the second parallel branch circuit of the U-phase winding passes are: 2(1)→11(2)→19(1)→28(2)→39(1)→48(2)→3(3)→12(4)→20(3)→29(4)→37(3)→46(4)→1(5)→10(6)→21(5)→30(6)→38(5)→47(6)→2(7)→47 (7)→39(7)→39(7)→30(7)→19(7)→10(7)→1(6)→46(5)→38(6)→29(5)→21(6)→12(5)→3(4)→48(3)→37(4)→28(3)→20(4)→11(3)→2(2)→47(1)→39(2)→30(1)→19(2)→10(1).

[0089] The slot numbers through which the series connection of the third parallel branch circuit of the U-phase winding passes are: 3(1)→12(2)→20(1)→29(2)→37(1)→46(2)→1(3)→10(4)→21(3)→30(4)→38(3)→47(4)→2(5)→11(6)→19(5)→28(6)→39(5)→48(6)→3(7) →48(7)→37(7)→28(7)→20(7)→11(7)→2(6)→47(5)→39(6)→30(5)→19(6)→10(5)→1(4)→46(3)→38(4)→29(3)→21(4)→12(3)→3(2)→48(1)→37(2)→28(1)→20(2)→11(1).

[0090] In another application scenario, still using a 6-pole, 54-slot flat wire motor as an example, the number of status lots 11 in the stator core 10 is 54, the number of poles in the rotor is 6, the number of slots per pole per phase is 3, and the number of slot layers N in each status lot 11 is 8. The stator windings are divided into U-phase, V-phase, and W-phase, and the number of parallel branch circuits provided in each phase winding is 3.

[0091] As shown in Figure 14, Figure 14 is a schematic diagram of the winding of the U-phase winding in a 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 8.

[0092] As shown in Figure 14, the slot numbers through which the series connection of the first parallel branch of the U-phase winding passes are: 1(1)→10(2)→21(1)→30(2)→38(1)→47(2)→2(3)→11(4)→19(3)→28(4)→39(3)→48(4)→3(5)→12(6)→20(5)→29(6)→37(5)→46(6)→1(7)→10(8)→21(7) →30(8)→38(7)→47(8)→1(8)→46(7)→38(8)→29(7)→21(8)→12(7)→3(6)→48(5)→37(6)→28(5)→20(6)→11(5)→2(4)→47(3)→39(4)→30(3)→19(4)→10(3)→1(2)→46(1)→38(2)→29(1)→21(2)→12(1).

[0093] The slot numbers through which the series connection of the second parallel branch circuit of the U-phase winding passes are: 2(1)→11(2)→19(1)→28(2)→39(1)→48(2)→3(3)→12(4)→20(3)→29(4)→37(3)→46(4)→1(5)→10(6)→21(5)→30(6)→38(5)→47(6)→2(7)→11(8)→19(7)→28(8 )→39(7)→48(8)→2(8)→47(7)→39(8)→30(7)→19(8)→10(7)→1(6)→46(5)→38(6)→29(5)→21(6)→12(5)→3(4)→48(3)→37(4)→28(3)→20(4)→11(3)→2(2)→47(1)→39(2)→30(1)→19(2)→10(1).

[0094] The slot numbers through which the series connection of the third parallel branch of the U-phase winding passes are: 3(1)→12(2)→20(1)→29(2)→37(1)→46(2)→1(3)→10(4)→21(3)→30(4)→38(3)→47(4)→2(5)→11(6)→19(5)→28(6)→39(5)→48(6)→3(7)→12(8)→20(7)→29(8) )→37(7)→46(8)→3(8)→48(7)→37(8)→28(7)→20(8)→11(7)→2(6)→47(5)→39(6)→30(5)→19(6)→10(5)→1(4)→46(3)→38(4)→29(3)→21(4)→12(3)→3(2)→48(1)→37(2)→28(1)→20(2)→11(1).

[0095] In another application scenario, still using a 6-pole, 54-slot flat wire motor as an example, the number of status lots 11 in the stator core 10 is 54, the number of rotor poles is 6, the number of slots per pole per phase is 3, and the number of slot layers N in each status lot 11 is 9. The stator windings are divided into U-phase, V-phase, and W-phase, and the number of parallel branch circuits provided in each phase winding is 3.

[0096] As shown in Figure 15, Figure 15 is a schematic diagram of the winding of the U-phase winding in a 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 9.

[0097] As shown in Figure 15, the slot numbers through which the series connection of the first parallel branch of the U-phase winding passes are: 1(1)→10(2)→21(1)→30(2)→38(1)→47(2)→2(3)→11(4)→19(3)→28(4)→39(3)→48(4)→3(5)→12(6)→20(5)→29(6)→37(5)→46(6)→1(7)→10(8)→21(7)→30(8)→38(7)→47(8) →2(9)→47(9)→39(9)→30(9)→19(9)→10(9)→1(8)→46(7)→38(8)→29(7)→21(8)→12(7)→3(6)→48(5)→37(6)→28(5)→20(6)→11(5)→2(4)→47(3)→39(4)→30(3)→19(4)→10(3)→1(2)→46(1)→38(2)→29(1)→21(2)→12(1).

[0098] The slot numbers through which the series connection of the second parallel branch circuit of the U-phase winding passes are: 2(1)→11(2)→19(1)→28(2)→39(1)→48(2)→3(3)→12(4)→20(3)→29(4)→37(3)→46(4)→1(5)→10(6)→21(5)→30(6)→38(5)→47(6)→2(7)→11(8)→19(7)→26(8)→39(7)→48(8)→3(9) →46(9)→37(9)→28(9)→20(9)→11(9)→2(8)→47(7)→39(8)→30(7)→19(8)→10(7)→1(6)→46(5)→38(6)→29(5)→21(6)→12(5)→3(4)→48(3)→37(4)→28(3)→20(4)→11(3)→2(2)→47(1)→39(2)→30(1)→19(2)→10(1).

[0099] The slot numbers through which the series connection of the third parallel branch circuit of the U-phase winding passes are: 3(1)→12(2)→20(1)→29(2)→37(1)→46(2)→1(3)→10(4)→21(3)→30(4)→38(3)→47(4)→2(5)→11(6)→19(5)→28(6)→39(5)→48(6)→3(7)→12(8)→20(7)→29(8)→37(7)→46(8)→1(9) →46(9)→38(9)→29(9)→21(9)→12(9)→3(8)→48(7)→37(8)→28(7)→20(8)→11(7)→2(6)→47(5)→39(6)→30(5)→19(6)→10(5)→1(4)→46(3)→38(4)→29(3)→21(4)→12(3)→3(2)→48(1)→37(2)→28(1)→20(2)→11(1).

[0100] In another application scenario, we still use a 6-pole, 54-slot flat wire motor as an example, where the number of status lots 11 in the stator core 10 is 54, the number of poles in the rotor is 6, the number of slots per pole per phase is 3, and the number of slot layers N in each status lot 11 is 10. The stator windings are divided into U-phase, V-phase, and W-phase, and the number of parallel branch circuits provided in each phase winding is 3.

[0101] As shown in Figure 16, Figure 16 is a schematic diagram of the winding of the U-phase winding in a 6-pole, 54-slot flat wire motor according to the present invention, when the number of slot layers is 10.

[0102] As shown in Figure 16, the slot numbers through which the series connection of the first parallel branch of the U-phase winding passes are: 1(1)→10(2)→21(1)→30(2)→38(1)→47(2)→2(3)→11(4)→19(3)→28(4)→39(3)→48(4)→3(5)→12(6)→20(5)→29(6)→37(5)→46(6)→1(7)→10(8)→21(7)→30(8)→38(7)→47(8)→2(9)→11(10)→19(9)→2 8(10)→39(9)→48(10)→2(10)→47(9)→39(10)→30(9)→19(10)→10(9)→1(8)→46(7)→38(8)→29(7)→21(8)→12(7)→3(6)→48(5)→37(6)→28(5)→20(6)→11(5)→2(4)→47(3)→39(4)→30(3)→19(4)→10(3)→1(2)→46(1)→38(2)→28(1)→21(2)→12(1).

[0103] The slot numbers through which the series connection of the second parallel branch of the U-phase winding passes are: 2(1)→11(2)→19(1)→28(2)→39(1)→48(2)→3(3)→12(4)→20(3)→29(4)→37(3)→46(4)→1(5)→10(6)→21(5)→30(6)→38(5)→47(6)→2(7)→11(8)→19(7)→26(8)→39(7)→48(8)→3(9)→12(10)→20(9)→29(10) →37(9)→46(10)→3(10)→48(9)→37(10)→28(9)→20(10)→11(9)→2(8)→47(7)→39(8)→30(7)→19(8)→10(7)→1(6)→46(5)→38(6)→29(5)→21(6)→12(5)→3(4)→48(3)→37(4)→28(3)→20(4)→11(3)→2(2)→47(1)→39(2)→30(1)→19(2)→10(1).

[0104] The slot numbers through which the series connection of the third parallel branch circuit of the U-phase winding passes are: 3(1)→12(2)→20(1)→29(2)→37(1)→46(2)→1(3)→10(4)→21(3)→30(4)→38(3)→47(4)→2(5)→11(6)→19(5)→28(6)→39(5)→48(6)→3(7)→12(8)→20(7)→29(8)→37(7)→46(8)→1(9)→10(10)→21(9)→30(10) →36(9)→47(10)→1(10)→46(9)→38(10)→29(9)→21(10)→12(9)→3(8)→48(7)→37(8)→28(7)→20(8)→11(7)→2(6)→47(5)→39(6)→30(5)→19(6)→10(5)→1(4)→46(3)→38(4)→29(3)→21(4)→12(3)→3(2)→48(1)→37(2)→28(1)→20(2)→11(1).

[0105] Referring to Figure 3 in conjunction with Figure 4, the multiple hairpin coils 21 of each parallel branch circuit according to the present invention include a long-pitch hairpin coil with a pitch of s / (2p)+a, a full-pitch hairpin coil with a pitch of s / (2p), and a short-pitch hairpin coil with a pitch of s / (2p)+a-4, where a is an integer between 2 and 4.

[0106] In each parallel branch, the first leg 211 and second leg 212 of the short-segment hairpin coil are located in the k-th slot layer and the k+1-th slot layer, respectively; the first leg 211 and second leg 212 of the long-segment hairpin coil are located in the k+1-th slot layer and the k+2-th slot layer, respectively; and the first leg 211 and second leg 212 of the full-segment hairpin coil are both distributed in either the first slot layer or the n-th slot layer, where k is an odd number between 1 and n.

[0107] The voltage leads of the p parallel branch circuits of each phase winding are located within s status lots and in the same slot layer or adjacent slot layer of different status lots, and the neutral point leads of the p parallel branch circuits of each phase winding are located within s status lots and in the same slot layer or adjacent slot layer of different status lots, thereby simplifying the winding structure.

[0108] By concentrating the positions of the lead wires and neutral points of the three-phase windings in the same slot layer or adjacent slot layers of different status lots 11, and by concentrating the positions of the lead wires and neutral points of the parallel branch lines, the axial and radial space required for the windings can be reduced, thereby lowering the manufacturing difficulty of the flat wire motor.

[0109] Since the p parallel branch lines of each phase winding are rotationally symmetric with respect to the stator core 10, the voltage lead lines of the p parallel branch lines in the same phase winding are also rotationally symmetric with respect to the stator core 10, and the neutral point lead lines of the p parallel branch lines in the same phase winding are also rotationally symmetric with respect to the stator core 10. Furthermore, both the voltage lead lines and the neutral point lead lines are located in the same slot layer; for example, both the voltage lead lines and the neutral point lead lines are located in the first slot layer or the nth slot layer.

[0110] In this embodiment, in each phase winding, the voltage lead lines and neutral points of the p parallel branch lines are rotationally symmetrical along the circumferential direction of the stator core 10, thus avoiding the generation of circulating current.

[0111] In one embodiment, the welding pitch between the hairpin coils 21 in each parallel branch may be s / (2p), that is, the welding pitch between the hairpin coils 21 is the same as the pitch of the fully wound hairpin coil. In one embodiment, the welding pitch between the hairpin coils 21 in the parallel branch may not be equal to the pitch of the fully wound hairpin coil.

[0112] In one embodiment, a=3, the pitch of the long-segment hairpin coil is s / (2p)+3, the pitch of the full-segment hairpin coil is s / (2p), and the pitch of the short-segment hairpin coil is s / (2p)-1. In each parallel branch, hairpin coils of these three pitches exist simultaneously, and the hairpin coils of each parallel branch are provided across n slot layers in different status lots 11, thereby eliminating the potential phase difference due to the position of the slot layers of the p parallel branch.

[0113] In the above application scenario, the pitch of the short-wound hairpin coil may be 11, the pitch of the full-wound hairpin coil may be 12, and the pitch of the long-wound hairpin coil may be 15.

[0114] In the above application scenario, when k=1, the hairpin coil used between the first and second slot layers of the parallel branch is a short-pitch hairpin coil, the hairpin coil used between the second and third slot layers of the parallel branch is a long-pitch hairpin coil, and similarly, the hairpin coil used between the third and fourth slot layers of the parallel branch is a short-pitch hairpin coil, and the hairpin coil used between the fourth and fifth slot layers of the parallel branch is a long-pitch hairpin coil. Although not explained repeatedly, when a full-pitch hairpin coil is provided in the same slot layer, it is provided only in the first slot layer or the nth slot layer. Here, the winding method of each phase winding may be wave winding or overlapping winding.

[0115] As shown in Figures 17 to 19, Figure 17 is a schematic diagram of the winding of the first parallel branch of the U-phase winding in a 6-pole, 72-slot flat wire motor according to the present invention, where the number of slot layers is 4 and a is 3; Figure 18 is a schematic diagram of the winding of the second parallel branch of the U-phase winding in the flat wire motor shown in Figure 17; and Figure 19 is a schematic diagram of the winding of the third parallel branch of the U-phase winding in the flat wire motor shown in Figure 17.

[0116] In the diagram, solid lines indicate the connection method at the wire insertion end, and dashed lines indicate the connection method at the weld end. U1, U2, and U3 may be used as either voltage lead lines or neutral point lead lines, and X1, X2, and X3 may be used as either voltage lead lines or neutral point lead lines.

[0117] In the above application scenario, m=3, the number of status lots s=72, the number of pole pairs of the rotor p=3, the number of slots per pole per phase q=4, the number of slot layers of status lot 11 n=4, the pitch of the long-segment hairpin coil is 15, the pitch of the full-segment hairpin coil is 12, the pitch of the short-segment hairpin coil is 11, and the welding pitch between adjacent hairpin coils in a parallel branch is 12. In this case, the hairpin coil used between the first slot layer and the second slot layer of the parallel branch is a short-segment hairpin coil, and the parallel The hairpin coil used between the second and third slot layers of the branch circuit is a long-segment hairpin coil, the hairpin coil used between the third and fourth slot layers of the parallel branch circuit is a short-segment hairpin coil, and the full-segment hairpin coil is provided in the same slot layer, or only in the first or fourth slot layer. As a result, the stator winding 20 of this embodiment requires only five types of hairpin coils 21, and the stator winding 20 of this embodiment consists of three phase windings with a phase difference of 120 degrees in electrical angle.

[0118] The first parallel branch, second parallel branch, and third parallel branch of the U-phase winding in this embodiment will be described in detail below with reference to Figures 17, 18, and 19.

[0119] Here, the number i(j) indicates the j-th slot layer of the i-th slot; for example, 1(1) indicates the first slot layer of the first slot, and 7(2) indicates the second slot layer of the seventh slot.

[0120] As shown in Figure 17, the first parallel branch of the U-phase winding is drawn in from voltage lead position U1 and drawn out from neutral point lead position X1, and the slot numbers through which the series connection of the first parallel branch passes are 1(1)→13(2)→24(1)→36(2)→47(1)→59(2)→70(1)→10(2)→25(3)→ 37(4)→48(3)→60(4)→71(3)→11(4)→22(3)→34(4)→22(4)→10(3)→71(4)→59(3)→48(4)→36(3)→25(4)→13(3)→70(2)→58(1)→47(2)→35(1)→24(2)→12(1)→1(2)→61(1).

[0121] As shown in Figure 18, the second parallel branch of the U-phase winding is drawn in from voltage lead position U2 and drawn out from neutral point lead position X2, and the slot numbers through which the series connection of the second parallel branch passes are 71(1)→11(2)→22(1)→34(2)→49(3)→61(4)→72(3)→12(4)→23(3)→ 35(4)→46(3)→58(4)→46(4)→34(3)→23(4)→11(3)→72(4)→60(3)→49(4)→37(3)→22(2)→10(1)→71(2)→59(1)→48(2)→36(1)→25(2)→13(1)→25(1)→37(2)→48(1)→60(2).

[0122] As shown in Figure 19, the third parallel branch of the U-phase winding is drawn in from voltage lead position U3 and drawn out from neutral point lead position X3, and the slot numbers through which the series connection of the third parallel branch passes are 72(1)→12(2)→23(1)→35(2)→46(1)→58(2)→1(3)→13(4)→24(3)→ 36(4)→47(3)→59(4)→70(3)→10(4)→70(4)→58(3)→47(4)→35(3)→24(4)→12(3)→1(4)→61(3)→46(2)→34(1)→23(2)→11(1)→72(2)→60(1)→49(2)→37(1)→49(1)→61(2).

[0123] The number distribution of the start and end slots corresponding to the three parallel branch lines in the U-phase winding is as follows: U1 corresponds to 1(1), X1 corresponds to 61(1), U2 corresponds to 71(1), X2 corresponds to 60(2), U3 corresponds to 72(1), and X3 corresponds to 61(2). U1, U2, and U3 are connected in parallel, X1, X2, and X3 are connected in parallel, and finally they are connected by a busbar to form the completed U-phase winding.

[0124] The U-phase winding, V-phase winding, and W-phase winding are uniformly and symmetrically distributed on the circumference of the stator core 10. In this embodiment, the V-phase winding and W-phase winding are obtained by the U-phase winding rotating along the circumferential direction of the stator core 10 by a number of stator rods 11. The winding method for the V-phase winding and W-phase winding is omitted here.

[0125] Based on the above application scenario, i.e., m=3, number of status lots s=72, number of pole pairs of rotor p=3, and number of slots per pole per phase q=4, if the number of slot layers n of status lot 11 is 6, the pitch of the long-segment hairpin coil is 15, the pitch of the full-segment hairpin coil is 12, the pitch of the short-segment hairpin coil is 11, and the welding pitch between adjacent hairpin coils in a parallel branch is 12, then the hairpin coil used between the first and second slot layers of the parallel branch is a short-segment hairpin coil, and the hairpin coil used between the second and third slot layers of the parallel branch is a long-segment hairpin coil, and parallel The hairpin coil used between the third and fourth slot layers of the branch circuit is a short-wound hairpin coil, the hairpin coil used between the fourth and fifth slot layers of the parallel branch circuit is a long-wound hairpin coil, the hairpin coil used between the fifth and sixth slot layers of the parallel branch circuit is a short-wound hairpin coil, and the full-wound hairpin coil is provided in the same slot layer, and is provided only in the first or sixth slot layer. As a result, the stator winding 20 of this embodiment requires only seven types of hairpin coils 21, and the stator winding 20 of this embodiment consists of three phase windings with a phase difference of 120 degrees in electrical angle.

[0126] As shown in Figure 20, the first parallel branch of the U-phase winding is drawn in from voltage lead position U1 and drawn out from neutral point lead position X1, and the slot numbers through which the series connection of the first parallel branch passes are 1(1)→13(2)→24(1)→36(2)→47(1)→59(2)→70(1)→10(2)→25(3)→37(4)→48(3)→60(4)→71(3)→11(4)→22(3)→34(4)→49(5)→ 61(6)→72(5)→12(6)→23(5)→35(6)→46(5)→58(6)→46(6)→34(5)→23(6)→11(5)→72(6)→60(5)→49(6)→37(5)→22(4)→10(3)→71(4)→59(3)→48(4)→36(3)→25(4)→13(3)→70(2)→58(1)→47(2)→35(1)→24(2)→12(1)→1(2)→61(1).

[0127] As shown in Figure 21, the second parallel branch of the U-phase winding is drawn in from voltage lead position U2 and drawn out from neutral point lead position X2, and the slot numbers through which the series connection of the second parallel branch passes are 71(1)→11(2)→22(1)→34(2)→49(3)→61(4)→72(3)→12(4)→23(3)→35(4)→46(3)→58(4)→1(5)→13(6)→24(5)→36(6)→47( 5)→59(6)→70(5)→10(6)→70(6)→58(5)→47(6)→35(5)→24(6)→12(5)→1(6)→61(5)→46(4)→34(3)→23(4)→11(3)→72(4)→60(3)→49(4)→37(3)→22(2)→10(1)→71(2)→59(1)→36(1)→25(2)→13(1)→25(1)→37(2)→48(1)→60(2).

[0128] As shown in Figure 22, the third parallel branch of the U-phase winding is drawn in from voltage lead position U3 and drawn out from neutral point lead position X3, and the slot numbers through which the series connection of the third parallel branch passes are (1)→12(2)→23(1)→35(2)→46(1)→58(2)→1(3)→13(4)→24(3)→36(4)→47(3)→59(4)→70(3)→10(4)→25(5)→37(6)→48(5)→6 0(6)→71(5)→11(6)→22(5)→34(6)→22(6)→10(5)→71(6)→59(5)→48(6)→36(5)→25(6)→13(5)→70(4)→58(3)→47(4)→35(3)→24(4)→12(3)→1(4)→61(3)→46(2)→34(1)→23(2)→11(1)→72(2)→60(1)→49(2)→37(1)→49(1)→61(2).

[0129] The number distribution of the start and end slots corresponding to the three parallel branch lines in the U-phase winding is as follows: U1 corresponds to 1(1), X1 corresponds to 61(1), U2 corresponds to 71(1), X2 corresponds to 60(2), U3 corresponds to 72(1), and X3 corresponds to 61(2). U1, U2, and U3 are connected in parallel, X1, X2, and X3 are connected in parallel, and finally they are connected by a busbar to form the completed U-phase winding.

[0130] Based on the above application scenario, namely m=3, the number of status lots s=72, the number of pole pairs of the rotor p=3, and the number of slots per pole per phase q=4, if the number of slot layers of the status lot 11 is n=8, the pitch of the long-segment hairpin coil is 15, the pitch of the full-segment hairpin coil is 12, and the pitch of the short-segment hairpin coil is 11. Thus, the stator winding 20 in this embodiment requires only nine types of hairpin coils 21.

[0131] As shown in Figure 23, the first parallel branch of the U-phase winding is drawn in from voltage lead position U1 and drawn out from neutral point lead position X1, and the slot numbers through which the series connection of the first parallel branch passes are 1(1)→13(2)→24(1)→36(2)→47(1)→59(2)→70(1)→10(2)→25(3)→37(4)→48(3)→60(4)→71(3)→11(4)→22(3)→34(4)→49(5)→61(6)→72(5)→12(6)→23(5)→35(6)→46(5)→58(6)→1(7)→ 13(8)→24(7)→36(8)→47(7)→59(8)→70(7)→10(8)→70(8)→58(7)→47(8)→35(7)→24(8)→12(7)→1(8)→61(7)→46(6)→34(5)→23(6)→11(5)→72(6)→60(5)→49(6)→37(5)→22(4)→10(3)→71(4)→59(3)→48(4)→36(3)→25(4)→13(3)→70(2)→58(1)→47(2)→35(1)→24(2)→12(1)→1(2)→61(1).

[0132] As shown in Figure 24, the second parallel branch of the U-phase winding is drawn in from voltage lead line position U2 and drawn out from neutral point lead line position X2, and the slot numbers through which the series connection of the second parallel branch is passed are 71(1)→11(2)→22(1)→34(2)→49(3)→61(4)→72(3)→12(4)→23(3)→35(4)→46(3)→58(4)→1(5)→13(6)→24(5)→36(6)→47(5)→59(6)→70(5)→10(6)→25(7)→37(8)→48(7)→60(8)→71( 7)→11(8)→22(7)→34(8)→22(8)→10(7)→71(8)→59(7)→48(8)→36(7)→25(8)→13(7)→70(6)→58(5)→47(6)→35(5)→24(6)→12(5)→1(6)→61(5)→46(4)→34(3)→23(4)→11(3)→72(4)→60(3)→49(4)→37(3)→22(2)→10(1)→71(2)→59(1)→36(1)→25(2)→13(1)→25(1)→37(2)→48(1)→60(2).

[0133] As shown in Figure 25, the third parallel branch of the U-phase winding is drawn in from voltage lead position U3 and drawn out from neutral point lead position X3, and the slot numbers through which the series connection of the third parallel branch passes are 72(1)→12(2)→23(1)→35(2)→46(1)→58(2)→1(3)→13(4)→24(3)→36(4)→47(3)→59(4)→70(3)→10(4)→25(5)→37(6)→48(5)→60(6)→71(5)→11(6)→22(5)→34(6)→49(7)→61(8)→72(7)→ 12(8)→23(7)→35(8)→46(7)→58(8)→46(8)→34(7)→23(8)→11(7)→72(8)→60(7)→49(8)→37(7)→22(6)→10(5)→71(6)→59(5)→48(6)→36(5)→25(6)→13(5)→70(4)→58(3)→47(4)→35(3)→24(4)→12(3)→1(4)→61(3)→46(2)→34(1)→23(2)→11(1)→72(2)→60(1)→49(2)→37(1)→49(1)→61(2).

[0134] The number distribution of the start and end slots corresponding to the three parallel branch lines in the U-phase winding is as follows: U1 corresponds to 1(1), X1 corresponds to 61(1), U2 corresponds to 71(1), X2 corresponds to 60(2), U3 corresponds to 72(1), and X3 corresponds to 61(2). U1, U2, and U3 are connected in parallel, X1, X2, and X3 are connected in parallel, and finally they are connected by a busbar to form the completed U-phase winding.

[0135] In another application scenario, when a=4, the pitch of the long-segment hairpin coil is s / (2p)+4, the pitch of the full-segment hairpin coil is s / (2p), and the pitch of the short-segment hairpin coil is also s / (2p). That is, the short-segment hairpin coil is also treated as a full-segment hairpin coil, and the first leg 211 and the second leg 212 of the short-segment hairpin coil (full-segment hairpin coil) are located in the k-th slot layer and the k+1-th slot layer, respectively.

[0136] In the above application scenario, the number of status lots is s = 6pq, the number of slot layers n in status lot 11 is even, and a = 4. Therefore, in this embodiment, the short-segment hairpin coil is changed to a full-segment hairpin coil. As shown in Figure 26, in the phase band distribution of the three-phase winding, the polarity distribution of each odd-numbered layer is the same, the polarity distribution of each even-numbered layer is the same, and is shifted by one status lot relative to the polarity distribution of the odd-numbered layer.

[0137] In this invention, the hairpin coils of the parallel branch paths in each phase winding are provided across n slot layers in different status lots 11, and the winding method of the winding may be wave winding or overlapping winding, and after a certain number of status lots 11 have been moved by a parallel branch path in the same phase winding, it overlaps with other parallel branch paths in the same winding. By using only two types of hairpin coils, long-section hairpin coils and full-section hairpin coils, the number of hairpin coil types that need to be used is greatly reduced, the number of molds that need to be manufactured is reduced, costs are reduced, and the efficiency of processing and manufacturing is improved. At the same time, regarding the phase band distribution of the three-phase winding, the positions of the adjacent q slots of the same polarity in the parallel branch paths in the same phase winding are shifted by one slot to the adjacent pole, the equivalent pitch of a certain phase is made smaller than the full-section winding pitch, the effect of short-section winding is realized, the back EMF harmonics of the flat wire motor are reduced, the efficiency of the flat wire motor is improved, and the NVH of the vehicle, i.e., noise, vibration and harshness, is optimized.

[0138] In the above application scenario, the number of slot layers n in the status lot 11 may be an even number such as 2, 4, 6, 8, or 10, each phase winding includes three parallel branch lines, and the combination of pitches of the hairpin coils 21 in each parallel branch line is 12 or 16, that is, the pitch of the long-section winding hairpin coil is 16, the pitch of the full-section winding hairpin coil is 12, and the welding pitch between the hairpin coils in each parallel branch line is 11 in all cases.

[0139] In another application scenario, a 6-pole, 72-slot motor is used as an example, where m=3, the number of status lots s=72, the number of pole pairs of the rotor p=3, the number of slots per pole per phase q=4, the number of slot layers n=4 for status lot 11, the pitch of the long-segment hairpin coil is 16, and the pitch of the full-segment hairpin coil is 12.

[0140] In the above application scenario, using the first winding method, the stator winding 20 requires only five types of hairpin coils.

[0141] As shown in Figure 27, the first parallel branch of the U-phase winding is drawn in from voltage lead position U1 and drawn out from neutral point lead position X1, and the slot numbers through which the series connection of the first parallel branch passes are 1(1)→12(2)→24(1)→35(2)→47(1)→58(2)→70(1)→9(2)→25(3)→3 6(4)→48(3)→59(4)→71(3)→10(4)→22(3)→33(4)→21(4)→10(3)→70(4)→59(3)→47(4)→36(3)→24(4)→13(3)→69(2)→58(1)→46(2)→35(1)→23(2)→12(1)→72(2)→61(1).

[0142] As shown in Figure 28, the second parallel branch of the U-phase winding is drawn in from voltage lead position U2 and drawn out from neutral point lead position X2, and the slot numbers through which the series connection of the second parallel branch passes are 71(1)→10(2)→22(1)→33(2)→49(3)→60(4)→72(3)→11(4)→23(3)→ 34(4)→46(3)→57(4)→45(4)→34(3)→22(4)→11(3)→71(4)→60(3)→48(4)→37(3)→21(2)→10(1)→70(2)→59(1)→47(2)→36(1)→24(2)→13(1)→25(1)→36(2)→48(1)→59(2).

[0143] As shown in Figure 29, the third parallel branch of the U-phase winding is drawn in from voltage lead position U3 and drawn out from neutral point lead position X3, and the slot numbers through which the series connection of the third parallel branch passes are 72(1)→11(2)→23(1)→34(2)→46(1)→57(2)→1(3)→12(4)→24(3)→ 35(4)→47(3)→58(4)→70(3)→9(4)→69(4)→58(3)→46(4)→35(3)→23(4)→12(3)→72(4)→61(3)→45(2)→34(1)→22(2)→11(1)→71(2)→60(1)→48(2)→37(1)→49(1)→60(2).

[0144] The number distribution of the start and end slots corresponding to the three parallel branch lines in the U-phase winding is as follows: U1 corresponds to 1(1), X1 corresponds to 61(1), U2 corresponds to 71(1), X2 corresponds to 59(2), U3 corresponds to 72(1), and X3 corresponds to 60(2). U1, U2, and U3 are connected in parallel, X1, X2, and X3 are connected in parallel, and finally connected by a busbar to form the completed U-phase winding. U1, U2, and U3 are located within q=4 adjacent status lots 11 of the same polarity, and X1, X2, and X3 are similarly located within q=4 adjacent status lots 11 of the same polarity.

[0145] In the above application scenario, a second winding method may be used, and the stator winding 20 requires only four types of hairpin coils.

[0146] Here, the number distribution of the start and end slots corresponding to the three parallel branch lines in the U-phase winding is as follows: U1 corresponds to 1(1), X1 corresponds to 61(1), U2 corresponds to 25(1), X2 corresponds to 13(1), U3 corresponds to 49(1), and X3 corresponds to 37(1). U1, U2, and U3 are connected in parallel, X1, X2, and X3 are connected in parallel, and finally connected by a busbar to form the completed U-phase winding. U1, U2, and U3 are rotationally symmetric with respect to the stator core 10, and each is shifted by 11 minutes of 24 status lots. Similarly, X1, X2, and X3 are also rotationally symmetric with respect to the stator core 10, and each is shifted by 11 minutes of 24 status lots.

[0147] In the second winding configuration, the first parallel branch of the U-phase winding is drawn in from voltage lead position U1 and drawn out from neutral point lead position X1, and the slot numbers through which the series connection of the first parallel branch passes are 1(1)→12(2)→24(1)→35(2)→47(1)→58(2)→70(1)→9(2)→25(3)→ 36(4)→48(3)→59(4)→71(3)→10(4)→22(3)→33(4)→21(4)→10(3)→70(4)→59(3)→47(4)→36(3)→24(4)→13(3)→69(2)→58(1)→46(2)→35(1)→23(2)→12(1)→72(2)→61(1).

[0148] The second parallel branch of the U-phase winding is drawn in from voltage lead line position U2 and drawn out from neutral point lead line position X2, and the slot numbers through which the series connection of the second parallel branch is passed are 25(1)→36(2)→48(1)→59(2)→71(1)→10(2)→22(1)→33(2)→49(3)→60(4)→72(3)→11(4)→23(3)→34(4)→46(3)→57(4)→45(4)→34(3)→22(4)→11(3)→71(4)→60(3)→48(4)→37(3)→21(2)→10(1)→70(2)→59(1)→47(2)→36(1)→24(2)→13(1).

[0149] The third parallel branch of the U-phase winding is drawn in from voltage lead line position U3 and drawn out from neutral point lead line position X3, and the slot numbers through which the series connection of the third parallel branch is passed are 49(1)→60(2)→72(1)→11(2)→23(1)→34(2)→46(1)→57(2)→1(3)→12(4)→24(3)→35(4)→47(3)→58(4)→70(3)→9(4)→69(4)→58(3)→46(4)→35(3)→24(4)→12(3)→72(4)→61(3)→45(2)→34(1)→22(2)→11(1)→71(2)→60(1)→48(2)→37(1).

[0150] Taking a 6-pole, 72-slot motor as an example, if m=3, the number of status lots s=72, the number of pole pairs of the rotor p=3, the number of slots per pole per phase q=4, and the number of slot layers n=6 in the status lot 11, then in this embodiment, the first winding method is used, and seven types of hairpin coils are required in the stator winding 20. The distribution of start and end slot numbers corresponding to the three parallel branch paths in the U-phase winding is as follows: U1 corresponds to 1(1), X1 corresponds to 61(1), U2 corresponds to 71(1), X2 corresponds to 59(2), U3 corresponds to 72(1), and X3 corresponds to 60(2). U1, U2, and U3 are connected in parallel, X1, X2, and X3 are connected in parallel, and finally connected by a busbar to form a completed U-phase winding, where U1, U2, and U3 are located within q=4 adjacent status lots 11 of the same polarity, and X1, X2, and X3 are also located within q=4 adjacent status lots 11 of the same polarity.

[0151] As shown in Figure 30, the first parallel branch of the U-phase winding is drawn in from voltage lead position U1 and drawn out from neutral point lead position X1, and the slot numbers through which the series connection of the first parallel branch passes are 1(1)→12(2)→24(1)→35(2)→47(1)→58(2)→70(1)→9(2)→25(3)→36(4)→48(3)→59(4)→71(3)→10(4)→22(3)→33(4)→49(5)→60(6)→72(5)→11(6 )→23(5)→34(6)→46(5)→57(6)→45(6)→34(5)→22(6)→11(5)→71(6)→60(5)→48(6)→34(5)→22(6)→11(5)→71(6)→60(5)→48(6)→37(5)→21(4)→10(3)→70(4)→59(3)→47(4)→36(3)→24(4)→13(3)→69(2)→58(1)→46(2)→35(1)→23(2)→12(1)→61(1).

[0152] As shown in Figure 31, the second parallel branch of the U-phase winding is drawn in from voltage lead position U2 and drawn out from neutral point lead position X2, and the slot numbers through which the series connection of the second parallel branch passes are 71(1)→10(2)→22(1)→33(2)→49(3)→60(4)→72(3)→11(4)→23(3)→34(4)→46(3)→57(4)→1(5)→12(6)→24(5)→35(6)→47(5)→ 58(6)→70(5)→9(6)→69(6)→58(5)→46(6)→35(5)→23(6)→12(5)→72(6)→61(5)→45(4)→34(3)→22(4)→11(3)→71(4)→60(3)→48(4)→37(3)→21(2)→10(1)→70(2)→59(1)→47(2)→36(1)→24(2)→13(1)→25(1)→36(2)→48(1)→59(2).

[0153] As shown in Figure 32, the third parallel branch of the U-phase winding is drawn in from voltage lead position U3 and drawn out from neutral point lead position X3, and the slot numbers through which the series connection of the third parallel branch passes are 72(1)→11(2)→23(1)→34(2)→46(1)→57(2)→1(3)→12(4)→24(3)→35(4)→47(3)→58(4)→70(3)→9(4)→25(5)→36(6)→48(5)→5 9(6)→71(5)→10(6)→22(5)→33(6)→21(6)→10(5)→70(6)→59(5)→47(6)→36(5)→24(6)→13(5)→69(4)→58(3)→46(4)→35(3)→23(4)→12(3)→72(4)→61(3)→45(2)→34(1)→22(2)→11(1)→71(2)→60(1)→48(2)→37(1)→49(1)→60(2).

[0154] Using the second winding method, the stator winding 20 requires only six types of hairpin coils, and the number distribution of the start and end slots corresponding to the three parallel branch lines in the U-phase winding is as follows: U1 corresponds to 1(1), X1 corresponds to 61(1), U2 corresponds to 25(1), X2 corresponds to 13(1), U3 corresponds to 49(1), and X3 corresponds to 37(1).

[0155] The slot numbers through which the series connection of the first parallel branch passes are the same as above, so the explanation is omitted.

[0156] The slot numbers through which the series connection of the second parallel branch circuit passes are: 25(1)→36(2)→48(1)→59(2)→71(1)→10(2)→22(1)→33(2)→49(3)→60(4)→72(3)→11(4)→23(3)→34(4)→46(3)→57(4)→1(5)→12(6)→24(5)→35(6)→47(5)→58(6)→ 70(5)→9(6)→69(6)→58(5)→46(6)→35(5)→23(6)→12(5)→72(6)→61(5)→45(4)→34(3)→22(4)→11(3)→71(4)→60(3)→48(4)→37(3)→21(2)→10(1)→70(2)→59(1)→47(2)→36(1)→24(2)→13(1).

[0157] The slot numbers through which the series connection of the third parallel branch circuit passes are: 49(1)→60(2)→72(1)→11(2)→23(1)→34(2)→46(1)→57(2)→1(3)→12(4)→24(3)→35(4)→47(3)→58(4)→70(3)→9(4)→25(5)→36(6)→48(5)→59(6)→71(5)→10(6)→2 2(5)→33(6)→21(6)→10(35)→70(6)→59(5)→47(6)→36(5)→24(6)→13(5)→69(4)→58(3)→46(4)→35(3)→23(4)→12(3)→72(4)→61(3)→45(2)→34(1)→22(2)→11(1)→71(2)→60(1)→48(2)→37(1).

[0158] In other application scenarios, when a=2, the pitch of a long-wound hairpin coil is s / (2p)+2, the pitch of a full-wound hairpin coil is s / (2p), and the pitch of a short-wound hairpin coil is s / (2p)-2.

[0159] Specifically, the number of status lots s may be 72, the number of pole pairs p of the rotor is 3, the number of slot layers n of the status lot 11 may be one of 4, 6, 8, and 10, the pitch of the long-segment hairpin coil is 14, the pitch of the full-segment hairpin coil is 12, and the pitch of the short-segment hairpin coil is 10. That is, the combinations of pitches of the hairpin coils 21 in each parallel branch are 10, 12, and 14, and the welding pitch between the hairpin coils in each parallel branch is 13 in all cases.

[0160] As an example, a 6-pole, 72-slot motor has m=3, the number of status lots s=72, the number of pole pairs of the rotor p=3, the number of slots per pole per phase q=4, and the number of slot layers of status lot 11 n=4.

[0161] In the above application scenario, using the first winding method, the stator winding 20 requires only five types of hairpin coils.

[0162] As shown in Figure 33, the first parallel branch of the U-phase winding is drawn in from voltage lead position U1 and drawn out from neutral point lead position X1. The slot numbers through which the series connection of this first parallel branch passes are 72(1)→13(2)→23(1)→36(2)→46(1)→59(2)→69(1)→10(2)→24(3). →37(4)→47(3)→60(4)→70(3)→11(4)→21(3)→34(4)→22(4)→9(3)→71(4)→58(3)→48(4)→35(3)→25(4)→12(3)→70(2)→57(1)→47(2)→34(1)→24(2)→11(1)→1(2)→60(1).

[0163] As shown in Figure 34, the second parallel branch of the U-phase winding is drawn in from voltage lead position U2 and drawn out from neutral point lead position X2. The slot numbers through which the series connection of this second parallel branch passes are 70(1)→11(2)→21(1)→34(2)→48(3)→61(4)→71(3)→12(4)→22(3). →35(4)→45(3)→58(4)→46(4)→33(3)→23(4)→10(3)→72(4)→59(3)→49(4)→36(3)→22(2)→9(1)→71(2)→58(1)→48(2)→35(1)→25(2)→12(1)→24(1)→37(2)→47(1)→60(2).

[0164] As shown in Figure 35, the third parallel branch of the U-phase winding is drawn in from voltage lead position U3 and drawn out from neutral point lead position X3. The slot numbers through which the series connection of this third parallel branch passes are 71(1)→12(2)→22(1)→35(2)→45(1)→58(2)→72(3)→13(4)→23(3). →36(4)→46(3)→59(4)→69(3)→10(4)→70(4)→57(3)→47(4)→34(3)→24(4)→11(3)→1(4)→60(3)→46(2)→33(1)→23(2)→10(1)→72(2)→59(1)→49(2)→36(1)→48(1)→61(2).

[0165] The number distribution of the start and end slots corresponding to these three parallel branch paths is as follows: U1 corresponds to 72(1), X1 corresponds to 60(1), U2 corresponds to 70(1), X2 corresponds to 60(2), U3 corresponds to 71(1), and X3 corresponds to 61(2).

[0166] In the above application scenario, using the second winding method, the stator winding 20 requires only four types of hairpin coils. Compared to the first winding method, the start and end slots of the parallel branch lines are different, and the specific winding method can be found in the first winding method described above, so the explanation is omitted here. Here, the number distribution of the start and end slots corresponding to the three parallel branch lines is as follows: U1 corresponds to 72(1), X1 corresponds to 60(1), U2 corresponds to 24(1), X2 corresponds to 12(1), U3 corresponds to 48(1), and X3 corresponds to 36(1).

[0167] Taking a 6-pole, 72-slot motor as an example, m=3, the number of status lots s=72, the number of pole pairs of the rotor p=3, the number of slots per pole per phase q=4, and the number of slot layers of status lot 11 n=6. In this embodiment, the first winding method is used, and seven types of hairpin coils are required in the stator winding 20.

[0168] As shown in Figure 36, the first parallel branch of the U-phase winding is drawn in from voltage lead position U1 and drawn out from neutral point lead position X1. The slot numbers through which the series connection of this first parallel branch passes are 72(1)→13(2)→23(1)→36(2)→46(1)→59(2)→69(1)→10(2)→24(3)→37(4)→47(3)→60(4)→70(3)→11(4)→21(3)→34(4)→48(5). →61(6)→71(5)→12(6)→22(5)→35(6)→45(5)→58(6)→46(6)→33(5)→23(6)→10(5)→72(6)→59(5)→49(6)→36(5)→22(4)→9(3)→71(4)→58(3)→48(4)→35(3)→25(4)→12(3)→70(2)→57(1)→47(2)→34(1)→24(2)→11(1)→1(2)→60(1).

[0169] As shown in Figure 37, the second parallel branch of the U-phase winding is drawn in from voltage lead position U2 and drawn out from neutral point lead position X2. The slot numbers through which the series connection of this second parallel branch passes are 70(1)→11(2)→21(1)→34(2)→48(3)→61(4)→71(3)→12(4)→22(3)→35(4)→45(3)→58(4)→72(5)→13(6)→23(5)→36(6)→46(5) →59(6)→69(5)→10(6)→70(6)→57(5)→47(6)→34(5)→24(6)→11(5)→1(6)→60(5)→46(4)→33(3)→23(4)→10(3)→72(4)→59(3)→49(4)→36(3)→22(2)→9(1)→71(2)→58(1)→48(2)→35(1)→25(2)→12(1)→24(1)→37(2)→47(1)→60(2).

[0170] As shown in Figure 38, the third parallel branch of the U-phase winding is drawn in from voltage lead position U3 and drawn out from neutral point lead position X3. The slot numbers through which the series connection of this third parallel branch passes are 71(1)→12(2)→22(1)→35(2)→45(1)→58(2)→72(3)→3(4)→23(3)→36(4)→46(3)→59(4)→69(3)→10(4)→24(5)→37(6)→47(5) →60(6)→70(5)→11(6)→21(5)→34(6)→22(6)→9(5)→71(6)→58(5)→48(6)→35(5)→25(6)→12(5)→70(4)→57(3)→47(4)→34(3)→24(4)→11(3)→1(4)→60(3)→46(2)→33(1)→23(2)→10(1)→72(2)→59(1)→49(2)→36(1)→48(1)→61(2).

[0171] The number distribution of the start and end slots corresponding to the three parallel branch lines in the U-phase winding is as follows: U1 corresponds to 72(1), X1 corresponds to 60(1), U2 corresponds to 70(1), X2 corresponds to 60(2), U3 corresponds to 71(1), and X3 corresponds to 61(2).

[0172] After winding using the winding method according to the embodiment of the present application, the back EMF harmonic content at the peak torque operating point of a 6-pole, 72-slot flat wire motor was compared. The back EMF harmonic content of a conventional fully wound motor was 4.75%, while the back EMF harmonic content using the embodiment of the present application was 3.98%, a decrease of 16.2%. This shows that the winding method according to the present application reduces back EMF harmonics and improves motor efficiency.

[0173] According to another aspect of the present invention, a powertrain is further provided, the powertrain including a reduction gear and the flat wire motor, wherein the flat wire motor is transmitted to the reduction gear. Specifically, the drive shaft of the flat wire motor and the input shaft of the reduction gear are transmitted by a transmission member such as a shaft coupling, and the driving force is output from the flat wire motor to the reduction gear.

[0174] In yet another embodiment of the present invention, a vehicle including the above-mentioned powertrain is further provided, the powertrain being installed within the vehicle and providing the vehicle with driving power. Specifically, in this embodiment, the vehicle may be a new energy vehicle driven by electrical energy. Specifically, the new energy vehicle may be a hybrid electric vehicle, a pure electric vehicle, or a fuel cell electric vehicle, and may be a vehicle that uses a highly efficient accumulator such as a supercapacitor, flywheel battery, or flywheel accumulator as an electrical energy source.

[0175] Unlike the prior art, this application discloses a stator, a flat wire motor, a powertrain, and a vehicle. Multiple parallel branch paths of each phase winding are rotationally symmetric in the circumferential direction. Thus, the magnetic field distribution of the multiple parallel branch paths in each phase winding is the same, and the potential is balanced. This avoids circulating currents generated between the parallel branch paths, significantly reduces additional AC copper losses at high frequencies, improves the efficiency of the flat wire motor during high-speed operation, avoids localized overheating of the windings, and extends the service life of the flat wire motor. Furthermore, the hairpin coils of each parallel branch path are provided across N slot layers in different status lots. This eliminates potential phase differences due to the position of the multiple parallel branch paths of each phase winding in the status lots. By limiting the number of slot layers N in the status lot and the total number of slot layers occupied by each corresponding parallel branch path in each status lot, the wire type of the hairpin coil can be reduced, the number of manufacturing molds for the flat wire motor can be reduced, manufacturing costs can be lowered, and the efficiency of processing and manufacturing can be effectively improved.

[0176] In this description, any reference to terms such as “one embodiment,” “several embodiments,” “example,” “specific example,” or “several examples” means that the specific features, structures, materials, or properties described in relation to such embodiment or example are included in at least one embodiment or example of this application. In this specification, a general expression for the above terms does not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, materials, or properties can be combined in any suitable manner in one or more embodiments or examples. Notwithstanding the fact that, persons skilled in the art can combine and link different embodiments or examples and features of different embodiments or examples described herein, provided that they do not conflict with each other.

[0177] The above describes only embodiments of the present application and does not limit the scope of the patent. For the same reasons, transformations of equivalent structures or equivalent flows, or direct or indirect applications to other related technical fields, made using the contents of the specification and drawings of the present application are included within the scope of the patent protection of the present application.

Claims

1. It is the stator of a flat wire motor, The inner wall has a stator core in which multiple status rods are uniformly arranged along its circumferential direction, Including stator windings, The stator winding includes a three-phase winding, each phase winding includes a plurality of parallel branch lines, the plurality of parallel branch lines are rotationally symmetric in the circumferential direction, each of the parallel branch lines is connected by connecting wires and includes a plurality of hairpin coils with different pitches, N layers of the hairpin coils are provided within each status lot, the hairpin coils of each parallel branch line are provided across N slot layers in different status lots, and the three-phase winding is arranged sequentially and periodically along the circumferential direction of the stator core. When N = (2n + 1) × 2, the combination of the total number of slot layers occupied by each of the parallel branch paths in each of the status lots is either 2n, or 2n, 2n-1, 2n-2. When N = 2n × 2, the combinations of the total number of slot layers occupied by each of the status lots in each of the parallel branch paths are 2n, 2n-1, or 2n, 2n-1, 2n-2. When N = 2n + 1, the combinations of the total number of slot layers occupied by each of the parallel branch paths in each of the status lots are n, n-1, or n, n-1, n-2. N is a positive integer and is 4 or greater, and the total number of slot layers in each status lot of each parallel branch is also a positive integer, statator, Each of the parallel branch circuits includes a long-segment hairpin coil with a pitch of s / (2p)+a, a full-segment hairpin coil with a pitch of s / (2p), and a short-segment hairpin coil with a pitch of s / (2p)+a-4. s is the number of status lots, p is the number of parallel branch lines, and a is an integer between 2 and 4.

2. If each of the parallel branch paths occupies a total of 1 slot layers in the status lot, the position of one slot layer is the first or nth layer of the status lot. If the total number of slot layers occupied by each parallel branch path in the status lot is 2, then the two slot layers are provided adjacent to each other in the status lot, or the two slot layers are the first layer and the Nth layer, respectively, in the status lot. If each of the parallel branch paths occupies a total of three slot layers in the status lot, then two of the three slot layers are located adjacent to each other, and the remaining slot layer is located in the first or nth layer of the status lot, and is separated from the other two slot layers by four slot layers. The stator according to claim 1, wherein, if each of the parallel branch paths occupies a total of four slot layers in the status lot, the four slot layers are divided into two groups, each group is provided separated by four slot layers, and each group includes two adjacent slot layers.

3. The stator according to claim 2, wherein each phase winding includes three parallel branch circuits.

4. The stator according to claim 3, wherein the number of status lots is 54 or 72.

5. The stator according to claim 3 or 4, wherein the combination of hairpin coil pitches in each of the parallel branch lines is 8, 9, 11, 12, and 16.

6. The stator according to claim 3 or 4, wherein the pitch of the hairpin coils in the same slot layer of each parallel branch is 9.

7. The stator according to claim 3 or 4, wherein the pitch of the hairpin coils in the first slot layer or the Nth slot layer of each parallel branch is 8 or 8, 11.

8. Each of the parallel branch lines has an entry end located in the Nth layer of the slot layer, and an exit end located in the N-1th layer of the slot layer, or The stator according to claim 3 or 4, wherein the input and output ends of each parallel branch are both located in the first slot layer and the Nth slot layer.

9. The stator according to claim 3 or 4, wherein the welding pitch between the hairpin coils in each of the parallel branch lines is 9 or 11.

10. In each of the parallel branch lines, the first and second legs of the short-segment hairpin coil are located in the k-th slot layer and the k+1 slot layer, respectively; the first and second legs of the long-segment hairpin coil are located in the k+1 slot layer and the k+2 slot layer, respectively; and the first and second legs of the full-segment hairpin coil are distributed in either the first slot layer or the nth slot layer. The statator according to claim 1, wherein k is an odd number between 1 and n, inclusive.

11. The number of slots per pole per phase of the flat wire motor is q, and the voltage lead lines of the p parallel branch paths of each phase winding are located within s status lots and are located in the same slot layer or adjacent slot layers of different status lots. The stator according to claim 10, wherein the neutral point lead wires of the p parallel branch circuits of each phase winding are located within s status lots and are located in the same slot layer or adjacent slot layers of different status lots.

12. The stator according to claim 11, wherein both the voltage lead line and the neutral point lead line are located in the first slot layer or the nth slot layer.

13. The stator according to claim 11, wherein the welding pitch between the hairpin coils in each of the parallel branch lines is s / (2p).

14. The stator according to claim 10, wherein n is an even number, a = 4, the short-segment hairpin coil is the full-segment hairpin coil, and in the phase band distribution of the three-phase windings, the polarity distribution of each odd-numbered layer is the same, the polarity distribution of each even-numbered layer is the same, and is shifted by one status lot with respect to the polarity distribution of the odd-numbered layer.

15. The stator according to claim 10, wherein the number of slot layers of the status lot is one of 4, 6, 8, and 10, the combination of hairpin coil pitches in each of the parallel branch lines is 10, 12, and 14, and the welding pitch between the hairpin coils in each of the parallel branch lines is 13.

16. The stator according to claim 1, wherein each hairpin coil includes a first leg, a second leg, a connecting segment, a first bent segment, and a second bent segment, the first leg and the second leg are arranged in parallel and inserted into slot layers of different stator lots, the connecting segment is connected to one end of the first leg and the second leg, the first bent segment is connected to the other end of the first leg, the second bent segment is connected to the other end of the second leg, and both the first bent segment and the second bent segment have welded ends connected to them.

17. The stator according to claim 16, wherein the bending directions of the first bending segment and the second bending segment are the same and parallel, or arranged symmetrically.

18. A rotor and a stator according to any one of claims 1 to 4, The rotor is a flat wire motor, provided within the space enclosed by the inner wall of the stator core.

19. The set includes a reduction gear and the flat wire motor described in claim 18, The flat wire motor is a powertrain that is driven to the reduction gear.

20. A vehicle comprising the powertrain described in claim 19.

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