Flat wire stator winding

Abstract

The utility model discloses a flat wire stator winding, the flat wire stator winding acts in stator slots of a stator core, the flat wire stator winding comprises a three-phase winding, the three-phase winding comprises a plurality of coils, the plurality of coils are wound in the stator slots, each stator slot is provided with even number layers of PIN wires, and lead-in wires and lead-out wires in the coils are arranged on the outermost two layers of PIN wires, the outer side of the flat wire stator winding is one side far away from the inner diameter space of the stator core, the flat wire stator winding is provided with a plurality of torsion head ends, and the plurality of torsion head ends are arranged at different torsion pitches. The multiple coils are evenly distributed in the circumferential direction of the stator core, balance of space and potential is achieved at the same time, the lead-in wire and the lead-out wire are arranged on the two layers of PIN wires on the outermost side, the arrangement of different torsion pitches is combined, the current path and the phase relation can be adjusted, electromagnetic interference is reduced, and the power factor and efficiency of the motor are improved.

Description

Technical Field

[0001] This application relates to the field of motor technology, and more specifically to a flat wire stator winding. Background Technology

[0002] In the field of electric motors, with the rapid development of modern industry and technology, the requirements for motor performance are becoming increasingly stringent. Traditional round and flat wire stator windings have low space utilization due to the large gaps between the wires, which limits the improvement of motor power density. Flat wire stators, on the other hand, use flat-shaped conductors that can be tightly arranged to effectively fill the stator slot space, significantly improving the winding fill rate. This allows for a substantial increase in the number of winding turns within the same volume, thereby increasing the motor's output power and meeting the urgent needs of modern industry for miniaturized and high-power-density motors.

[0003] With the rapid development of new energy vehicles, industrial automation, and other fields, more stringent requirements have been placed on motor performance. As a core component, the motor needs to have high efficiency, high power density, and good heat dissipation performance. The application of flat wire stators makes it possible to meet these requirements. Their compact structure and good electrical performance help improve motor efficiency and reduce energy loss.

[0004] However, flat wire stators still face some challenges in practical applications. While they offer advantages in space utilization and power density, existing designs fall short in terms of magnetic field optimization. Firstly, traditional winding layouts and torsional pitch settings result in an unreasonable current distribution within the windings, leading to uneven magnetic field distribution, significant electromagnetic interference, and reduced motor power factor and efficiency. Secondly, achieving precise spatial and potential balance is difficult when multi-phase windings work together, further impacting the overall motor performance.

[0005] Therefore, how to optimize the structural design of flat wire stators to achieve a more uniform magnetic field distribution while ensuring the spatial and potential balance of multiphase windings has become a key issue that urgently needs to be addressed in the current development of flat wire stator technology. Utility Model Content

[0006] The purpose of this application is to provide a flat wire stator winding, thereby optimizing the structural design of the flat wire stator to achieve a more uniform magnetic field distribution, while ensuring the spatial and potential balance of the multiphase winding.

[0007] To achieve the above objectives, the technical solution adopted in this application is as follows: a flat wire stator winding is provided, wherein the flat wire stator winding acts in the stator slot of the stator core, the flat wire stator winding includes: a three-phase winding, wherein the three-phase winding includes multiple coils, the multiple coils are wound in the stator slot, each stator slot is provided with an even number of PIN wires, and the lead wires and lead wires of the coils are arranged on the outermost two PIN wires, the outer side being the side away from the inner diameter space of the stator core, and the flat wire stator winding is provided with multiple twist ends, the multiple twist ends being configured with unequal torsional pitch.

[0008] As a preferred embodiment, each phase of the three-phase winding is configured as a branch circuit, and each branch circuit is formed by connecting PIN lines spanning full pitch and PIN lines spanning short pitch.

[0009] As another preferred embodiment, the PIN wires are arranged radially from the outside to the inside of the stator core as follows: short-pitch PIN wires spanning 1-1 layers, full-pitch PIN wires spanning 1-2 layers, full-pitch PIN wires spanning 2-3 layers, full-pitch PIN wires spanning 3-4 layers, and short-pitch PIN wires spanning 4-4 ​​layers. Each PIN wire includes a first soldering end, a first twisted section, a first straight section, a U-shaped end, a second straight section, a second twisted section, and a second soldering end connected in sequence.

[0010] Further preferably, the first and second twisting segments of the short-pitch PIN lines spanning 1-1 layers and the short-pitch PIN lines spanning 4-4 ​​layers all twist in the same direction; the first and second twisting segments of the full-pitch PIN lines spanning 1-2 layers, the short-pitch PIN lines spanning 2-3 layers, and the full-pitch PIN lines spanning 3-4 layers all twist in opposite directions, twisting away from the center to both sides.

[0011] Further preferably, the first twisting segment and the second twisting segment in the short-pitch PIN line spanning 1-1 layers twist in the same direction in a first direction, and the first twisting segment and the second twisting segment in the short-pitch PIN line spanning 4-4 ​​layers twist in the same direction in a second direction, wherein the first direction and the second direction are opposite.

[0012] More preferably, the winding group includes one to four layers of winding groups arranged sequentially from the outer side to the inner side, and the three-phase lead wires of the full-pitch PIN wire spanning 1-2 layers are all located in the first layer of winding group.

[0013] Preferably, the star points of the three-phase windings are all located in the second layer of the winding group.

[0014] Preferably, the short-pitch PIN wires spanning 4-4 ​​layers are arranged as the innermost PIN wires in the same layer, and all of them are formed radially toward the inner side, so that the short-pitch PIN wires spanning 4-4 ​​layers bulge toward the inner diameter space of the stator core.

[0015] Preferably, the pitch formed by the second twist segment and the second solder end in the full-pitch spanning 1-2 layers of PIN wire of type YI is different from the pitch formed by the other twist segments and solder ends.

[0016] Further preferred, an electric motor is also provided, the electric motor comprising: a motor rotor; a motor stator, the motor stator being connected to the motor rotor, and the motor stator comprising the flat wire stator described in any one of the above embodiments.

[0017] Compared with the prior art, the beneficial effects of this application are as follows:

[0018] The stator core preferably has 48 circumferentially equidistant stator slots extending axially, and the flat wire stator preferably has four layers of pin wires, arranged radially from the outermost island to the innermost island as the first, second, third, and fourth layers. Multiple coils are wound in the stator slots with evenly distributed three-phase windings, resulting in a more uniform magnetic field distribution. The even distribution of multiple coils around the stator core also achieves spatial and potential balance. The lead-in and lead-out wires are located on the outermost two layers of pin wires. Combined with the non-equivalent torsional pitch setting, the current path and phase relationship can be adjusted, reducing electromagnetic interference and improving the motor's power factor and efficiency. Furthermore, the non-equivalent torsional pitch setting allows for a more compact winding layout, reducing flat wire length and resistance, lowering copper losses, and improving the motor's energy efficiency. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a flat wire stator;

[0020] Figure 2 A schematic diagram of the welded side of a flat wire stator;

[0021] Figure 3 A schematic diagram of the U-shaped side of a flat wire stator;

[0022] Figure 4 This is a schematic diagram of the stator core structure;

[0023] Figure 5 This is a schematic diagram of a short-pitch PIN line spanning 1-1 layers;

[0024] Figure 6 A schematic diagram of a PIN line spanning 1-2 layers with a full pitch;

[0025] Figure 7 A schematic diagram of a PIN line spanning 2-3 layers with a full pitch;

[0026] Figure 8 A schematic diagram of a PIN line spanning 3-4 layers with a full pitch;

[0027] Figure 9 This is a schematic diagram of a short-pitch PIN line spanning 4-4 ​​layers;

[0028] Figure 10 A schematic diagram of a YI-type full-pitch PIN line spanning 1-2 layers;

[0029] Figure 11 This is a schematic diagram of the structure of the lead-in line;

[0030] Figure 12 This is a schematic diagram of the lead wire structure;

[0031] Figure 13 A schematic diagram of a YI-type full-pitch PIN wire spanning 1-2 layers placed within a flat wire stator winding;

[0032] Figure 14 This is the wiring diagram.

[0033] In the diagram: 1. Flat wire stator; 10. Stator core; 11. Flat wire stator winding; 12. Stator slot; 13. Inner diameter space; 14. Three-phase winding; 20a. Short-pitch PIN wire spanning 1-1 layers; 20b. Full-pitch PIN wire spanning 1-2 layers; 20c. Full-pitch PIN wire spanning 2-3 layers; 20d. Full-pitch PIN wire spanning 3-4 layers; 20e. Short-pitch PIN wire spanning 4-4 ​​layers; 20f. YI-type full-pitch PIN wire spanning 1-2 layers; 20g. Lead-in wire; 20h. Lead-out wire; 21. First welding end; 22. First twist section; 23. First straight section; 24. U-shaped end; 25. Second straight section; 26. Second twist section; 27. Second welding end. Detailed Implementation

[0034] The present application will be further described below with reference to specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0035] In the description of this application, it should be noted that the directional terms such as "center", "lateral", "longitudinal", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", and "counterclockwise" indicate the orientation and positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. They should not be construed as limiting the specific protection scope of this application.

[0036] It should be noted that the terms "first," "second," etc., in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0037] The terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are intended to cover non-exclusive inclusion, for example, a process, method, system, product, or device that includes a series of steps or units is not necessarily limited to those steps or units that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.

[0038] In a preferred embodiment, see Figures 1 to 13 This application provides a flat wire stator winding 11, which operates in the stator slot 12 of the stator core 10. The flat wire stator winding 11 includes a three-phase winding 14, which includes multiple coils wound in the stator slot 12. Each stator slot 12 has an even number of pin wires, and the lead wires 20g and 20h of the coils are arranged on the outermost two pin wires. The outer side is the side away from the inner diameter space 13 of the stator core 10. The flat wire stator winding 11 has multiple twist ends, and the multiple twist ends are set with unequal torsional pitch.

[0039] Specifically, the stator core 10 in this application preferably has 48 circumferentially equidistant stator slots 12 extending axially. The flat wire stator windings 11 cooperate with the stator core 10 to form the flat wire stator 1. The flat wire stator 1 in this application preferably has four layers of pin wires, arranged radially from the outermost layer to the innermost layer: the first layer, the second layer, the third layer, and the fourth layer. Multiple coils are wound in the stator slots 12, and the three-phase windings 14 are evenly distributed, resulting in a more uniform magnetic field distribution. The even circumferential distribution of multiple coils in the stator core 10 also achieves spatial and potential balance. The lead-in wire 20g and lead-out wire 20h are positioned on the outermost two layers of pin wires. Combined with the non-equivalent torsional pitch setting, the current path and phase relationship can be adjusted, reducing electromagnetic interference and improving the motor's power factor and efficiency. Simultaneously, each stator slot 12 has an even number of pin wire layers, increasing the number of winding turns. This increases the motor's output power and power density within the same volume, meeting the requirements for miniaturization and high performance.

[0040] Furthermore, the non-equivalent torsional pitch setting allows for a more compact winding layout, reduces flat wire length and resistance, lowers copper losses, and improves motor energy efficiency.

[0041] The 20g lead-in line and 20h lead-out line are set on the outermost two layers of PIN lines, which facilitates connection to external circuits, reduces manufacturing difficulty and cost, and the clear circuit layout also facilitates fault diagnosis and maintenance.

[0042] As a preferred embodiment, each phase of the three-phase winding 14 is configured as a branch circuit, and each branch circuit is formed by connecting PIN lines spanning full pitch and PIN lines spanning short pitch.

[0043] As another preferred embodiment, the PIN wires are arranged radially from the outside to the inside of the stator core 10 as follows: short-pitch PIN wires spanning 1-1 layers 20a, full-pitch PIN wires spanning 1-2 layers 20b, full-pitch PIN wires spanning 2-3 layers 20c, full-pitch PIN wires spanning 3-4 layers 20d, and short-pitch PIN wires spanning 4-4 ​​layers 20e. Each PIN wire includes a first soldering end 21, a first twisted section 22, a first straight section 23, a U-shaped end 24, a second straight section 25, a second twisted section 26, and a second soldering end 27 connected sequentially. The routing of the flat wire stator winding 11 is as follows: Figure 14 As shown in the wiring diagram.

[0044] The combination of different PIN wires across different layers, namely the pairing of short-pitch and full-pitch PIN wires, helps to make the magnetic field distribution within the motor more uniform. The short-pitch PIN wires spanning layers 1-1 (20a) and 4-4 (4-4), as well as the full-pitch PIN wires spanning layers 1-2, 2-3, and 3-4, generate magnetic fields in the stator core 10 that complement each other, reducing magnetic field distortion and non-uniformity. This, in turn, improves the efficiency and output torque of the motor when applied to it.

[0045] Arranging the PIN wires across different layers sequentially from the outside to the inside fully utilizes the radial space of the stator core 10, resulting in a more compact winding structure. This compact design helps reduce the size and weight of the motor, meeting the modern industrial demand for miniaturization and lightweight motors. Simultaneously, the rational spatial distribution of the PIN wires across different layers avoids interference between windings. Each PIN wire has its specific position and direction, making the winding arrangement within the stator slot 12 more orderly and reducing space waste and the possibility of electrical faults caused by winding crossings and overlaps.

[0046] The PIN wires uniformly adopt a structure consisting of a first soldering end 21, a first twisted section 22, a first straight section 23, a U-shaped end 24, a second straight section 25, a second twisted section 26, and a second soldering end 27 connected in sequence. This facilitates standardized production. Furthermore, when a motor malfunctions, this clear PIN wire structure and arrangement makes it easier for technicians to troubleshoot and repair the problem. The position and connection method of each PIN wire follow a predictable pattern, enabling rapid fault location and reducing repair time and costs.

[0047] The U-shaped end 24 of the PIN wire can be effectively fixed in the slot of the stator core 10, while the first straight segment 23 and the second straight segment 25 are respectively inserted into the corresponding stator slot 12 layers. This structural design gives the PIN wire good mechanical stability in the stator core 10.

[0048] Further preferred, the first twisting segment 22 and the second twisting segment 26 in the short-pitch PIN line 20a spanning 1-1 layers and the short-pitch PIN line 20e spanning 4-4 ​​layers both twist in the same direction; the first twisting segment 22 and the second twisting segment 26 in the full-pitch PIN line 20b spanning 1-2 layers, the short-pitch PIN line 2-3 layers, and the full-pitch PIN line 20d spanning 3-4 layers both twist in opposite directions, twisting away from the center on both sides.

[0049] In this design, the first and second twisting sections of the short-pitch PIN wires spanning layers 1-1 and 4-4 twist in the same direction, while the first and second twisting sections of the full-pitch PIN wires spanning layers 1-2, short-pitch PIN wires spanning layers 2-3, and full-pitch PIN wires spanning layers 3-4 twist in opposite directions. This arrangement allows the magnetic fields generated by different PIN wires to cooperate and cancel each other out, reducing interference between magnetic fields. At the same time, different twisting directions affect the distribution of current within the PIN wires. By reasonably setting the twisting direction of the PIN wires in this application, the current can be distributed more evenly in the winding, avoiding current concentration in certain areas that could lead to localized overheating, thereby improving the reliability and stability of the flat wire stator 1.

[0050] Furthermore, the short-pitch PIN lines across layers 1-1 and 4-4 twist in opposite directions, while the full-pitch and some short-pitch PIN lines twist in opposite directions. This layout allows the windings to be arranged more compactly within the stator core 10. The PIN lines with different twisting directions intersect each other, making full use of the space within the stator slot 12 and reducing the gaps between windings, thereby increasing the number of turns of the windings within a limited space.

[0051] In a further preferred embodiment, the first twisting segment 22 and the second twisting segment 26 in the short-pitch PIN line 20a spanning 1-1 layers twist in the same direction in the first direction, and the first twisting segment 22 and the second twisting segment 26 in the short-pitch PIN line 20e spanning 4-4 ​​layers twist in the same direction in the second direction, with the first direction and the second direction facing opposite directions.

[0052] Among them, the first and second twisting sections of the short-pitch PIN line 20a spanning layer 1-1 and the PIN line spanning layer 4-4 twist in opposite directions, making the direction and distribution of the magnetic field they generate more reasonable. This helps to reduce mutual interference of magnetic fields and make the magnetic field distribution in the entire stator more uniform. The uniform magnetic field distribution can effectively reduce the energy loss of the motor, improve the efficiency and power factor of the motor, and thus improve the overall performance of the motor.

[0053] Specifically, the short-pitch first and second twist sections of the PIN wire 20a spanning layer 1-1 and the PIN wire spanning layer 4-4 twist in opposite directions while twisting in the same direction, avoid spatial interference between these two types of PIN wires. During motor manufacturing, the installation and arrangement of the windings require precise control. If interference occurs between the PIN wires, it not only increases manufacturing difficulty but may also affect the performance and reliability of the motor. This arrangement allows the PIN wires to be arranged in an orderly manner, ensuring the neatness and stability of the windings.

[0054] Furthermore, the short-pitch, opposite-direction twisting arrangement of the PIN lines 20a across layer 1-1 and PIN lines across layer 4-4 allows them to restrain each other when subjected to electromagnetic forces and mechanical vibrations, enhancing the overall structural stability of the winding and helping to reduce winding deformation and loosening.

[0055] Preferably, the first straight segment 23 and the second straight segment 25 are respectively inserted into the corresponding stator slots 12, the U-shaped end 24 is located on the U-shaped side of the stator core 10, and the first welding end 21, the first twisting segment 22, the second twisting segment 26, and the second welding end 27 are located on the welding side of the stator core 10. Simultaneously, the first twisting segment 22 and the second twisting segment 26 twist after the PIN wires are inserted into the stator slots 12 of the stator core 10, and the PIN wires are welded together through the corresponding first welding end 21 or second welding end 27.

[0056] Further preferred, the winding group includes one to four layers of winding groups arranged sequentially from the outside to the inside, and the three-phase lead-out lines 20h of the full-pitch PIN lines 20b spanning 1-2 layers are all located in the first layer of winding group.

[0057] Preferably, the three-phase winding 14 in this application adopts a star (Y) connection, and the ends of the three windings converge to a common point. The connecting line at this point is called the "star line". The star lines of the three-phase winding 14 are all located in the second layer of the winding group. Specifically, the star line usually does not carry external current. Placing it in the second layer can optimize space utilization, and through layered layout, electromagnetic balance and potential symmetry of the windings can be achieved, reducing magnetic field interference. The first layer is used to arrange the lead wires 20h that need to be frequently connected to external circuits, and the second layer is used for the star line. This avoids wire bundle crossing and improves structural compactness. The lead wires 20h in the first layer can reduce electromagnetic interference to the internal windings. The star line in the second layer helps to balance the magnetic field distribution of the three-phase winding 14 and reduce harmonic content.

[0058] Preferably, the short-pitch PIN wires 20e spanning 4-4 ​​layers are arranged as the innermost PIN wires in the same layer, and all of them are formed radially inward, so that the short-pitch PIN wires 20e spanning 4-4 ​​layers convex toward the inner diameter space 13 of the stator core 10.

[0059] The innermost layer, also known as the fourth layer, has its PIN wires protruding inwards to avoid physical interference with the outer windings, freeing up more radial space for the rotor or heat dissipation structure. This is especially suitable for high-power-density motors (such as drive motors for new energy vehicles), which require efficient layout within a limited space.

[0060] The short-pitch 4-4 layer PIN wire 20e inner molding can enhance the fit between the winding and the stator core 10, reduce the winding displacement caused by centrifugal force during high-speed operation, reduce vibration and noise, and the compact layout of the short-pitch coil further strengthens the structural rigidity and adapts to high speed or frequent start-stop conditions.

[0061] Preferred, see Figure 10 and Figure 13 The pitch formed by the second twisted section 26 and the second welding end 27 in the YI-type full-pitch PIN wire 20f spanning 1-2 layers is different from the pitch formed by the other twisted sections and welding ends. The pitch refers to the angle and distance of the twist of the PIN wire twisted end in the flat wire winding. It should be noted that the twisted end formed by the second twisted section 26 and the second welding end 27 is the aforementioned twisted end.

[0062] Specifically, see Figure 13 The twist angle of the YI-type full-pitch PIN line 20f spanning 1-2 layers is different from that of the other full-pitch PIN lines 20b adjacent to it. That is, the twist angle of the second twist section 26 is different from the others, and it has the ability to adjust the tilt angle.

[0063] Meanwhile, the physical distance of the twisted end of the YI-type full-pitch PIN wire 20f spanning 1-2 layers differs from that of other PIN wires. Specifically, the space interval (slot pitch) between the second welding end 27 and the adjacent second straight segment 25 is differentiated. Preferably, the space interval between the second welding end 27 and the adjacent second straight segment 25 of the YI-type full-pitch PIN wire 20f spanning 1-2 layers is one unit, while the space interval between the second welding end 27 and the adjacent second straight segment 25 of the other full-pitch PIN wires 20b spanning 1-2 layers is two units. This setting can optimize electromagnetic performance. The differentiated pitch weakens the superposition effect of higher harmonics by adjusting the phase distribution of the coil. The asymmetrical distance design balances the inductance distribution of the three-phase winding 14, reduces electromagnetic imbalance, and thus reduces iron loss and copper loss. When applied to motors, it improves motor efficiency, especially under high-speed or high-load conditions.

[0064] Furthermore, while the YI-type full-pitch winding itself has a high induced electromotive force, traditional uniform pitch easily leads to localized magnetic field concentration. Therefore, this application uses differentiated pitch to adjust the magnetic field path, making the air gap magnetic field distribution more uniform, reducing leakage flux, and improving torque output stability. The pitch of the twisted end of the 1-2 layer PIN wire 20f in the YI-type full-pitch winding is different from that of other twisted ends, which can achieve spatial staggered arrangement, improve the structural compactness of the flat wire stator 1, avoid the radial or circumferential overlap of multi-layer welded ends, free up more space, and effectively reduce wire crossings, reducing the risk of short circuits. This is especially important in high-density flat wire windings, thereby improving power density and meeting the needs of miniaturized motors, such as drive motors for new energy vehicles.

[0065] Furthermore, the YI-type full-pitch PIN line 20f twist end setting, combined with the inner layer molding design, and the inner protruding structure of the PIN line 4-4 layers, further optimizes the spatial matching of the inner and outer layer windings by different pitches, avoiding mechanical interference.

[0066] Differential pitch disperses the weld ends circumferentially or radially, facilitating the positioning of automated welding tools, reducing blind spots, simplifying the manufacturing process, avoiding concentrated welding heat, and reducing the risk of insulation damage. Since the stator slots 12 in this application are preferably 48 arranged axially, if all weld ends have the same pitch, dense weld points may lead to excessive local temperature rise. Differential pitch disperses thermal stress. Furthermore, different torsion angles and distances can accommodate a step-by-step torsion process, processing the outer PIN wires first, then the inner layer, reducing tool interference.

[0067] Furthermore, this application enhances the winding's resistance to deformation by using differentiated torsion angles. Through the differentiated pitch design of torsion angle and physical distance, YI-type full-pitch PIN wires combined with an even number of four-layer PIN wires maximize space efficiency and achieve process and reliability upgrades. This design is a key technological breakthrough in the evolution of flat wire motors towards high performance, high density, and high reliability.

[0068] Further preferred, an electric motor is also provided, the electric motor including: a motor rotor; a motor stator connected to the motor rotor, and the motor stator is specifically any of the above-mentioned flat wire stator 1, the flat wire stator 1 including any of the above-mentioned flat wire stator windings 11.

[0069] The basic principles, main features, and advantages of this application have been described above. Those skilled in the art should understand that this application is not limited to the above embodiments. The embodiments and descriptions in the specification are merely the principles of this application. Various changes and modifications can be made to this application without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claims. The scope of protection claimed by this application is defined by the appended claims and their equivalents.

Claims

1. A flat wire stator winding, characterized in that, The flat wire stator winding acts in the stator slots of the stator core, and the flat wire stator winding includes: The three-phase winding includes multiple coils wound in the stator slots. Each stator slot has an even number of pin wires, and the lead wires and lead wires of the coils are arranged on the outermost two pin wires. The outer side is the side away from the inner diameter space of the stator core. The flat wire stator winding has multiple twist ends, and the multiple twist ends are set with unequal torsional pitch.

2. The flat wire stator winding as described in claim 1, characterized in that, Each phase of the three-phase winding is configured as a branch circuit, and each branch circuit is formed by connecting PIN lines spanning full pitch and PIN lines spanning short pitch.

3. The flat wire stator winding as described in claim 2, characterized in that, The PIN wires are arranged radially from the outside to the inside of the stator core as follows: short-pitch PIN wires spanning 1-1 layers, full-pitch PIN wires spanning 1-2 layers, full-pitch PIN wires spanning 2-3 layers, full-pitch PIN wires spanning 3-4 layers, and short-pitch PIN wires spanning 4-4 ​​layers. Each PIN wire includes a first soldering end, a first twisted section, a first straight section, a U-shaped end, a second straight section, a second twisted section, and a second soldering end connected in sequence.

4. The flat wire stator winding as described in claim 3, characterized in that, The first and second twisting segments of the short-pitch PIN line spanning 1-1 layers and the short-pitch PIN line spanning 4-4 ​​layers both twist in the same direction. The first and second twisting segments of the full-pitch PIN lines spanning 1-2 layers, the short-pitch PIN lines spanning 2-3 layers, and the full-pitch PIN lines spanning 3-4 layers all twist in opposite directions, turning away from the center to both sides.

5. The flat wire stator winding as described in claim 4, characterized in that, The first and second twisting segments in the short-pitch PIN line spanning 1-1 layers twist in the same direction in a first direction, and the first and second twisting segments in the short-pitch PIN line spanning 4-4 ​​layers twist in the same direction in a second direction, wherein the first and second directions are opposite.

6. The flat wire stator winding as described in claim 3, characterized in that, The winding assembly includes one to four layers of winding assemblies arranged sequentially from the outer side to the inner side, and the three-phase lead wires spanning 1-2 layers of PIN wires with full pitch are all located in the first layer of winding assembly.

7. The flat wire stator winding as described in claim 6, characterized in that, The star points of the three-phase windings are all located in the second layer of the winding group.

8. The flat wire stator winding as described in claim 5, characterized in that, The short-pitch PIN wires spanning 4-4 ​​layers are arranged as the innermost PIN wires in the same layer, and are all formed radially toward the inner side, so that the short-pitch PIN wires spanning 4-4 ​​layers bulge toward the inner diameter space of the stator core.

9. The flat wire stator winding as described in claim 5, characterized in that, The pitch formed by the second twist segment and the second solder end in the full-pitch spanning 1-2 layers of PIN wire of type YI is different from the pitch formed by the other twist segments and solder ends.

10. An electric motor, characterized in that, The motor includes: Motor rotor; An electric motor stator, which is connected to the electric motor rotor, and the electric motor stator includes a flat wire stator winding as described in any one of claims 1-9.

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