An improved winding optimization method for permanent magnet synchronous motor

Abstract

The application discloses an improved winding optimization method for a permanent magnet synchronous motor, comprising the following steps: setting the total number of turns of the winding of the permanent magnet synchronous motor based on the performance of the permanent magnet synchronous motor; forming a winding distribution structure in the winding layer in the motor slot after pre-encoding according to a bottom-up order based on the winding of the permanent magnet synchronous motor and a layout rule; designing an improved winding segmentation symmetrical return winding strategy, and winding the winding in each winding layer of the permanent magnet synchronous motor based on the winding distribution structure, so as to realize the winding optimization of the winding of the permanent magnet synchronous motor. The application solves the problems that the existing winding of the permanent magnet synchronous motor is deteriorated in broadband impedance characteristics under high-frequency working conditions due to the parasitic capacitance effect between windings, the traditional winding method does not fully consider the influence of the potential distribution between windings on the lumped parasitic capacitance, the electromagnetic interference of the motor is increased and the efficiency is reduced when the motor is operated at high frequency, and the winding optimization design theory based on the energy method lacks systematic guidance.

Description

Technical Field

[0001] This invention relates to the field of permanent magnet synchronous motor technology, and in particular to an improved method for optimizing the winding of permanent magnet synchronous motors. Background Technology

[0002] With the rapid development of new energy vehicles, industrial automation, rail transportation, aerospace, and intelligent manufacturing, permanent magnet synchronous motors (PMSMs) have become core actuators in electric drive systems due to their significant advantages such as high power density, high efficiency, and superior control performance. In these applications, the motors are typically driven by high-frequency pulse-width modulation (PWM) inverters, with the switching frequency of the drivers continuously increasing to achieve finer torque control and faster dynamic response. However, the steep voltage edges and rapid current changes generated by high-frequency switching have led to serious electromagnetic compatibility (EMC) problems in the motor system. Among these, common-mode conducted interference has become one of the key technical bottlenecks restricting the performance improvement and reliability assurance of motor drive systems.

[0003] Common-mode conducted noise propagates outwards through power lines, grounding loops, and parasitic coupling paths. This can cause not only internal signal distortion, controller malfunctions, and communication interference, but also disrupt the normal operation of peripheral equipment. In severe cases, it can even prevent the product from passing international electromagnetic compatibility (EMC) standard certifications, directly impacting market access and commercial applications. Therefore, suppressing common-mode conducted interference in permanent magnet synchronous motor systems and improving their EMC performance has become a core issue that urgently needs to be addressed in motor drive system design.

[0004] A thorough analysis of the common-mode interference propagation mechanism of permanent magnet synchronous motor systems reveals that, at high frequencies, the common-mode impedance characteristics of the motor are primarily dominated by parasitic capacitance. This parasitic capacitance mainly originates from the electric field coupling between the stator windings and the stator core and housing, and its magnitude directly determines the conduction path and propagation intensity of high-frequency common-mode noise current. When the inverter outputs a high-frequency common-mode voltage, this parasitic capacitance provides a low-impedance path for the common-mode current, allowing common-mode noise to propagate efficiently, thereby deteriorating the system's electromagnetic compatibility (EMC) performance. In other words, the parasitic capacitance of the stator windings is the key physical source of common-mode conducted interference; the larger its value, the stronger the conduction capability of common-mode noise, the lower the system's common-mode impedance, and the worse the EMC performance. To suppress common-mode conducted noise, existing technologies mainly employ the following methods: First, installing common-mode filters on the power supply or motor side, using common-mode inductors and Y capacitors to form a passive filter network, blocking the propagation path of common-mode noise; second, using active filtering technology to suppress noise by real-time detection and compensation of common-mode current; and third, optimizing PWM modulation strategies, such as using random modulation or spread spectrum modulation, to reduce the amplitude of the common-mode voltage or change its spectral distribution. However, these methods are all "end-of-pipe" solutions, meaning they suppress common-mode interference after it has already occurred. This not only increases the system's size, weight, and cost but is also constrained by factors such as the filter's own parasitic parameters, active circuit bandwidth limitations, and modulation algorithm complexity, making it difficult to achieve ideal suppression effects across the entire frequency band.

[0005] More importantly, current technologies do not address the common-mode conducted noise problem at its source; that is, they lack active methods to suppress parasitic capacitance in motor stator windings. Although some research in the field of magnetic components (such as transformers and inductors) has focused on the impact of winding structure on parasitic capacitance and proposed methods to reduce parasitic capacitance by optimizing winding arrangement, adjusting interlayer spacing, and introducing shielding layers, these technological achievements have not yet been systematically applied to the design of permanent magnet synchronous motor windings. Motor windings and magnetic component windings differ significantly in structural form, spatial constraints, and electromagnetic environment; directly copying the design methods of magnetic components is unlikely to achieve ideal results.

[0006] Furthermore, existing research on parasitic capacitance in motor windings largely focuses on modeling analysis and parameter calculation, lacking targeted engineering suppression solutions. Particularly at the winding process level, a systematic theoretical framework and practical methods have not yet been developed. Current motor windings typically follow the traditional principle of symmetrical distribution, primarily considering motor performance indicators such as electromagnetic torque uniformity and magnetomotive force harmonic suppression, without incorporating high-frequency common-mode impedance characteristics into the design optimization objectives. This results in traditional winding structures exhibiting significant parasitic capacitance at high frequencies, providing favorable conditions for common-mode noise propagation and hindering further improvements in the electromagnetic compatibility performance of motor systems.

[0007] Given the shortcomings of existing technologies, there is an urgent need for an innovative method that starts from the design of the motor itself, systematically reduces the parasitic capacitance of the stator windings by optimizing the winding method, thereby improving the wideband common-mode impedance of the motor and suppressing common-mode conducted noise. This method should be characterized by strong engineering feasibility, minimal cost increase, and good compatibility with existing manufacturing processes, effectively improving the high-frequency electromagnetic compatibility characteristics of the motor without significantly affecting its electromagnetic performance. Summary of the Invention

[0008] This invention provides an improved method for optimizing the winding of permanent magnet synchronous motors to overcome the aforementioned technical problems.

[0009] To achieve the above objectives, the technical solution of the present invention is as follows: An improved method for optimizing the winding of a permanent magnet synchronous motor specifically includes the following steps: S1: Set the total number of turns of the permanent magnet synchronous motor windings based on the performance of the permanent magnet synchronous motor; And the total number of turns is either odd or even; According to the layout rules, the permanent magnet synchronous motor windings are set in the winding layer in the pre-coded motor slot in a bottom-up order to form a winding distribution structure. S2: Design an improved segmented symmetrical rewinding strategy for windings, and perform winding on the windings in each winding layer of the permanent magnet synchronous motor based on the winding distribution structure, thereby optimizing the winding of the permanent magnet synchronous motor windings.

[0010] Furthermore, the deployment rules described in S1 are specifically as follows: Following a bottom-up order, the permanent magnet synchronous motor windings are arranged in each winding layer within the pre-coded motor slot. If the total number of turns in the permanent magnet synchronous motor windings is odd, then based on expert experience, the number of turns in the first winding layer is set to odd, and the number of turns in the remaining winding layers is set to even. If the total number of turns in the permanent magnet synchronous motor windings is even, then based on expert experience, the number of turns in the first winding layer is set to even, and the number of turns in the remaining winding layers is also set to even.

[0011] Furthermore, the improved segmented symmetrical rewinding strategy described in S2 specifically includes: S21: Obtain the number of winding turns in each winding layer of the winding distribution structure, and obtain the winding turn sequence table; S22: Based on the winding turn sequence table, wind each layer of winding sequentially, and perform the following steps for each layer of winding: S221: Determine the number of turns N of the winding in this layer; If the number of turns N is odd, then execute S222; if the number of turns N is even, then execute S224. S222: Determine the spatial arrangement order of the windings in this layer, and first wind the (N+1) / 2th turn winding located in the middle of the arrangement order in this layer and execute S223; S223: Using the middle winding as the center of symmetry, the remaining windings are wound alternately towards both ends of the layer; wherein, the two turns wound at each pair of symmetrical positions have opposite winding paths. S224: Determine the spatial arrangement order of the windings in this layer and their corresponding centerline positions. Using the centerline position as the center of symmetry, simultaneously wind all windings alternately towards both ends of this layer. Among them, the two turns of winding wound at each pair of symmetrical positions have opposite winding paths. After completing the winding of the m-th layer, the winding of the (m+1)-th layer is performed. Among them, the starting point of the winding of the (m+1)-th layer and the ending point of the winding of the m-th layer are spatially symmetrical with respect to the plane containing the central axis of the motor slot.

[0012] Furthermore, it also includes constructing a lumped parasitic capacitance calculation model for permanent magnet synchronous motor windings based on the energy method, and obtaining the parasitic capacitance of the winding system based on the lumped parasitic capacitance calculation model; And the expression for the lumped parasitic capacitance calculation model is:

[0013] In the formula: Represents lumped capacitance; This represents the potential difference between the first and last turns of each winding layer; This represents the total electric field energy after the windings in each winding layer of a permanent magnet synchronous motor are wound based on the winding distribution structure. This represents the capacitance between different turns; This represents the potential difference between different turns.

[0014] This invention provides an improved method for optimizing the winding of permanent magnet synchronous motors, with the following advantages: (1) Effectively reduces parasitic capacitance and enhances broadband impedance characteristics: By adopting an improved segmented symmetrical rewinding method, namely the improved segmented symmetrical rewinding strategy, the lumped parasitic capacitance can be significantly reduced, the winding self-resonant frequency can be greatly increased, the effective operating frequency range of the motor can be widened, the motor can maintain good impedance characteristics during high-frequency operation, avoid performance degradation and efficiency reduction caused by parasitic parameters, and meet the stringent requirements of modern power electronic systems for high-frequency motor performance.

[0015] (2) Optimize the winding potential distribution to achieve electric field equilibrium: By employing structural optimization techniques such as symmetrical winding from the middle to both ends, rationally setting the location of turnback points, and controlling the distribution of interlayer potential difference, the interlayer potential difference is effectively controlled within a small range, avoiding the problem of extremely large potential differences that occur in traditional winding methods. The optimized potential distribution significantly reduces the electric field intensity in high potential difference regions, lowers local electric field concentration and insulation stress, and improves the electrical reliability and service life of the winding. This is particularly suitable for applications with stringent insulation performance requirements, such as high-speed motors and servo motors.

[0016] (3) Significantly improves electromagnetic compatibility performance and anti-interference capability: By reducing parasitic capacitance, the high-frequency common-mode current path is reduced, effectively suppressing electromagnetic interference generated by the motor windings. At the same time, it enhances the resistance to external electromagnetic interference. In the variable frequency drive system, it can significantly reduce the common-mode voltage and shaft current caused by PWM high-frequency switching, reduce the electro-corrosion of bearings, and extend the overall service life of the motor. Moreover, the improved winding structure significantly improves the common-mode impedance over a wide frequency band, meeting the stringent EMC standard requirements and providing a reliable guarantee for the stable operation of the motor in complex electromagnetic environments.

[0017] (4) Possesses good engineering feasibility and wide applicability: The winding optimization method proposed in this invention can maintain the simplicity of the process. It can achieve performance optimization by simply adjusting the winding sequence, without changing the existing winding equipment and production process, without increasing the additional material and manufacturing costs. It is easy to implement on existing production lines and is applicable to various permanent magnet synchronous motors, including different rotor structures such as built-in and surface-mounted types. It can be widely used in new energy vehicle drive motors, industrial servo systems, high-speed electric spindles, aerospace actuators and other fields. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0019] Figure 1 This is a flowchart of the improved permanent magnet synchronous motor winding optimization method of the present invention; Figure 2 This is a schematic diagram of the internal structure of the motor slot in this embodiment; Figure 3 This is a schematic diagram of the winding of a traditional permanent magnet synchronous motor in this embodiment; Figure 4 This is a schematic diagram of the sequential winding of the windings in this embodiment; Figure 5 This is a schematic diagram of the potential distribution of the sequentially wound windings in this embodiment; Figure 6 This is a schematic diagram of the simple rewinding winding in this embodiment; Figure 7 This is a schematic diagram of the potential distribution of the winding in the simple folded-back winding in this embodiment; Figure 8 This is a schematic diagram of the improved segmented symmetrical rewinding in this embodiment; Figure 9 This is a schematic diagram of the potential distribution of the improved segmented symmetrical folded-back winding proposed in this embodiment. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] This embodiment provides an improved method for optimizing the winding of a permanent magnet synchronous motor, such as... Figure 1 As shown, the specific steps include: S1: Based on the performance of the permanent magnet synchronous motor, set the total number of turns of the permanent magnet synchronous motor winding, and the total number of turns is either odd or even; according to the layout rules, set the permanent magnet synchronous motor winding in the winding layer in the pre-coded motor slot in a bottom-up order to form a winding distribution structure. In this embodiment, the layout rule is as follows: the permanent magnet synchronous motor windings are arranged in each winding layer within the pre-coded motor slot in a bottom-up order; wherein, if the total number of turns of the permanent magnet synchronous motor windings is odd, the number of turns in the first winding layer is set to odd based on expert experience, and the number of turns in the remaining winding layers is set to even; if the total number of turns of the permanent magnet synchronous motor windings is even, the number of turns in the first winding layer is set to even based on expert experience, and the number of turns in the remaining winding layers is also set to even. Specifically, the method proposed in this embodiment provides a theoretical basis and structural guidance for the design of high-frequency windings in permanent magnet synchronous motors. It has good practicality and scalability, and is suitable for applications such as high-speed motors and servo motors that require high bandwidth impedance characteristics. Figure 2 The image shows the internal structure of the slots and windings of a permanent magnet synchronous motor. Traditional permanent magnet synchronous motor windings are constructed using a random winding method, such as... Figure 3As shown, the windings are randomly distributed within the slots without a specific winding sequence. While this winding method is simple and fast, the random proximity of high and low potential turns leads to extreme local potential differences and chaotic inter-layer and inter-turn capacitance distribution, resulting in a significant increase in lumped parasitic capacitance. According to the energy method principle, the total electric field energy of the winding system can be expressed as:

[0022] In the formula: Represents lumped capacitance; This refers to the capacitance between different turns, including inter-turn capacitance. Interlayer capacitance ; C_lump represents the potential difference between different turns; U represents the potential difference between the first and last turns. The value of C_lump mainly depends on the winding sequence: in random winding (i.e., irregular winding), the potential difference between any two turns depends on their position difference in the circuit, which may range from 1 to N-1; while in regular winding, the potential difference between adjacent turns is usually a unit value, and the potential difference between corresponding positions between layers depends on the specific winding sequence. The corresponding lumped equivalent capacitance can be calculated using the following formula:

[0023] From the formula It can be seen that to minimize the lumped capacitance C_lump, it is necessary to maintain... Without changing the total energy storage W, the goal is to minimize the total energy storage W for each unit of energy storage. Minimize as much as possible. In random winding, the random adjacency of high and low potential turns leads to extremely high energy storage; while in regular winding, the key to optimization lies in arranging the winding sequence reasonably to reduce capacitive coupling in the high potential difference region.

[0024] Furthermore, common regular winding methods in this embodiment include sequential winding and simple back-and-forth winding, such as... Figures 4 to 7 As shown: Sequential winding involves the first layer being wound continuously from the starting end to the ending end, and the second layer returning from the ending end to the starting end; simple fold-back winding involves folding back each layer at the end. These methods are improvements over random winding, but still suffer from the problem of large interlayer potential differences in some areas. Specifically, in sequential winding, the potential difference between upper and lower layers is extremely large near the fold-back point, while in simple fold-back winding, the interlayer potential difference is consistent and large for each layer. The capacitive energy storage in these high potential difference regions accounts for the majority of the total energy storage. To solve this problem, this embodiment proposes an improved segmented symmetrical fold-back winding method, specifically: S2: Design an improved segmented symmetrical folding winding strategy, which winds in each winding layer of the permanent magnet synchronous motor based on the winding distribution structure, thereby optimizing the winding of the permanent magnet synchronous motor winding. The improved segmented symmetrical rewinding strategy specifically includes the following steps: S21: Obtain the number of winding turns in each winding layer of the winding distribution structure, and obtain the winding turn sequence table; S22: Based on the winding turn sequence table, wind each layer of winding sequentially, and perform the following steps for each layer of winding: S221: Determine the number of turns N of the winding in this layer; If the number of turns N is odd, then execute S222; if the number of turns N is even, then execute S224. S222: Determine the spatial arrangement order of the windings in this layer, and first wind the (N+1) / 2th turn winding located in the middle of the arrangement order in this layer and execute S223; S223: Using the middle winding as the center of symmetry, the remaining windings are wound alternately towards both ends of the layer; wherein, the two turns wound at each pair of symmetrical positions have opposite winding paths. S224: Determine the spatial arrangement order of the windings in this layer and their corresponding centerline positions. Using the centerline position as the center of symmetry, simultaneously wind all windings alternately towards both ends of this layer. Among them, the two turns of winding wound at each pair of symmetrical positions have opposite winding paths. After completing the winding of the m-th layer, the winding of the (m+1)-th layer is performed. Among them, the starting point of the winding of the (m+1)-th layer and the ending point of the winding of the m-th layer are spatially symmetrical with respect to the plane containing the central axis of the motor slot.

[0025] The specific implementation process of the improved segmented symmetrical folding-back winding strategy in this embodiment is as follows: S21: Obtain the number of winding turns in each winding layer in the winding distribution structure, and obtain the winding turn sequence table; S22: Confirm the number of winding turns in the first winding layer of the winding turn sequence table; If the number of turns in the winding is odd, then continue executing S23; If the number of turns in the winding is odd, then continue executing S24; S23: Determine the intermediate winding turns in the first winding layer, and define the winding turns symmetrically arranged on both sides of the intermediate winding turns as the first winding to be wound and the second winding to be wound. The intermediate winding turns are first wound using a pre-set winding wire; and after the intermediate winding turns are wound, the first winding and the second winding are symmetrically wound using the winding wire in a direction extending from the middle to both ends. Furthermore, the winding paths of each winding in the first winding to be wound and the second winding to be wound are opposite in direction; S24: Define the number of turns of the winding in the first winding layer as a first winding to be wound and a second winding to be wound that are symmetrically arranged; And following the direction of extending from the middle to both ends, the first winding and the second winding are symmetrically wound using pre-set winding wires. Furthermore, the winding paths of each turn in the first winding and the second winding are opposite. S25: After winding the windings in the first winding layer, symmetrically set the outer sides of the windings at both ends of the first winding layer as turn-back points; And the windings in the second winding layer are wound symmetrically in a direction extending from both ends to the middle; Furthermore, the initial winding turns for winding the second winding layer are: Define the winding code sequence in the second winding layer and ,in respectively with Symmetrical; Indicates the first winding layer in the second winding layer One winding turn; Will As the starting winding turn; S26: Define the number of turns of the winding in the third winding layer as the fifth and sixth windings to be wound, which are symmetrically arranged; And in accordance with the direction extending from the middle to both ends, the fifth winding and the sixth winding to be wound are symmetrically wound by winding; and the winding directions of each winding turn in the fifth winding and the sixth winding to be wound are opposite. S27: After winding the windings in the third winding layer, the turning points will be symmetrically set on the outside of the windings at both ends of the third winding layer. And the windings in the fourth winding layer are wound symmetrically in a direction extending from both ends to the middle; Furthermore, the initial winding turns for winding the fourth winding layer are: Define the winding code sequence in the fourth winding layer and ,in respectively with Symmetrical; Indicates the fourth winding layer One winding turn; Will As the starting winding turn; ...... This process continues until all winding turns in all winding layers of the winding distribution structure are wound.

[0026] like Figure 8As shown, the core idea of ​​the method described in this embodiment is to start each layer of winding from the middle position and simultaneously wind it symmetrically towards both ends: after the first layer is completed, it is folded back at both ends to form the second layer, with the folding back point maintaining a distance of 2-3 turns from the end to reduce electric field coupling in the high potential region; the second layer continues to be wound symmetrically, with the folding back point also maintaining a distance of 2-3 turns from the end to maintain the potential continuity with the first layer. This winding method can effectively control the potential difference between corresponding positions between layers, making its distribution more uniform. The principle of potential distribution during the winding process is as follows: Figure 9 As shown in the diagram (i.e., the optimized winding path), the first layer starts from the middle and winds towards both ends, leaving an appropriate gap for folding back near the ends; if the number of turns in the first layer is odd, one turn is wound in the middle first, and then symmetrically wound towards both ends; the second layer is folded back simultaneously at both ends and continues to wind towards the middle while maintaining symmetry, and subsequent layers follow the same pattern, always maintaining the symmetry of the winding and the continuity of the potential distribution). Through comparative analysis, it can be clearly observed that compared to the traditional sequential winding method and the conventional simple folding winding method, the improved segmented symmetrical folding winding method proposed in this embodiment exhibits significant advantages in potential distribution characteristics. Specifically, after adopting this method, the potential difference between different regions of the winding is effectively controlled and significantly reduced. In sequential winding, because the coil is wound continuously from the starting end to the end, there is a large cumulative potential difference between adjacent layers, resulting in a highly uneven distribution of electric field intensity between layers, with high-potential regions concentrated at the winding ends. While simple folding winding alleviates the potential gradient to some extent through reciprocating motion, abrupt potential changes still occur at the folding points, and the phenomenon of electric field concentration in local areas still exists. In contrast, the improved segmented symmetrical folding winding method proposed in this embodiment can achieve an approximately symmetrical gradient change in the potential distribution of the entire winding by simultaneously unfolding from the middle to both ends and using a symmetrical folding structure at the ends. This layout not only makes the potential difference between adjacent turns and layers tend to be balanced, but also effectively avoids the direct adjacency of high and low potential regions, thereby significantly reducing the electric field coupling strength. In addition, by reserving an appropriate spacing at the folding points, high-potential regions are further isolated, making the overall potential distribution smoother and more continuous, ultimately achieving a uniform distribution of parasitic capacitance and an overall reduction in equivalent parasitic capacitance.

[0027] This embodiment also includes a lumped parasitic capacitance calculation model to obtain the parasitic capacitance of the winding system. Simulation calculations and theoretical analysis show that, using the method described in this embodiment, the lumped parasitic capacitance can be reduced by 50-70% compared to the traditional random winding method, and by 30-50% compared to sequential winding. This is because symmetrical folding winding effectively reduces the energy contribution of capacitance storage in high potential difference regions; at the same time, due to the reduction of lumped capacitance, the self-resonant frequency of the motor winding is increased, and the broadband impedance characteristics are significantly improved. In the method described in this embodiment, the first layer is wound synchronously from the center position to both sides, and each layer is folded back to form a second layer before the end. At least two turns of buffer are reserved between the folding point and the end point to weaken the field coupling effect in the high-voltage region. If the number of turns in the first layer is odd, the middle winding turns need to be wound once before turning. After that, each layer is symmetrically folded back at both ends to ensure the symmetrical structure and potential continuity of the winding, thereby effectively controlling the interlayer potential gradient, making the parasitic capacitance uniformly distributed, and thus reducing the overall equivalent parasitic capacitance value and improving the electromagnetic compatibility of the motor in high-frequency environments.

[0028] The beneficial effects of the method described in this embodiment are as follows: (1) Effectively reduces parasitic capacitance and enhances broadband impedance characteristics: The method described in this embodiment establishes an accurate calculation model of lumped capacitance based on the energy method, systematically analyzes the energy storage distribution law of inter-turn capacitance and inter-layer capacitance in the winding of permanent magnet synchronous motor, and adopts an improved segmented symmetrical folding winding method, which can significantly reduce lumped parasitic capacitance, greatly increase the winding self-resonant frequency, and widen the effective operating frequency range of the motor. This allows the motor to maintain good impedance characteristics during high-frequency operation, avoids performance degradation and efficiency reduction caused by parasitic parameters, and meets the stringent requirements of modern power electronic systems for the high-frequency performance of motors.

[0029] (2) Optimize the winding potential distribution to achieve electric field equilibrium: The method described in this embodiment effectively controls the interlayer potential difference within a small range by employing structural optimization techniques such as symmetrical winding from the middle to both ends, reasonable setting of turnback point positions, and control of the interlayer potential difference distribution. This avoids the problem of extremely large potential differences that occur in traditional winding methods. The optimized potential distribution significantly reduces the electric field intensity in high potential difference regions, reduces local electric field concentration and insulation stress, and improves the electrical reliability and service life of the winding. It is particularly suitable for applications with strict insulation performance requirements, such as high-speed motors and servo motors.

[0030] (3) Significantly improves electromagnetic compatibility performance and anti-interference capability: The method described in this embodiment reduces the high-frequency common-mode current path by decreasing parasitic capacitance, effectively suppressing electromagnetic interference generated by the motor windings, and enhancing resistance to external electromagnetic interference. In a variable frequency drive system, it can significantly reduce the common-mode voltage and shaft current caused by PWM high-frequency switching, reduce electro-corrosion of bearings, and extend the overall service life of the motor. The improved winding structure significantly improves the common-mode impedance over a wide frequency range, meeting stringent EMC standards and providing reliable assurance for the stable operation of the motor in complex electromagnetic environments.

[0031] (4) Possesses good engineering feasibility and wide applicability: The method described in this embodiment maintains process simplicity, achieving performance optimization simply by adjusting the winding sequence. It requires no changes to existing winding equipment and production processes, incurs no additional material or manufacturing costs, and is easily implemented on existing production lines. This method provides a clear design process and optimization criteria, facilitating understanding and application by engineers. The technical solution is applicable to various permanent magnet synchronous motors, including built-in and surface-mounted rotor structures, and can be widely used in new energy vehicle drive motors, industrial servo systems, high-speed electric spindles, aerospace actuators, and other fields.

[0032] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An improved method for optimizing the winding of a permanent magnet synchronous motor, characterized in that, Specifically, the following steps are included: S1: Set the total number of turns of the permanent magnet synchronous motor windings based on the performance of the permanent magnet synchronous motor; And the total number of turns is either odd or even; According to the layout rules, the permanent magnet synchronous motor windings are set in the winding layer in the pre-coded motor slot in a bottom-up order to form a winding distribution structure. S2: Design an improved segmented symmetrical rewinding strategy for windings, and based on the winding distribution structure, wind the windings in each winding layer of the permanent magnet synchronous motor to achieve winding optimization of the permanent magnet synchronous motor windings.

2. The improved method for optimizing the winding of a permanent magnet synchronous motor according to claim 1, characterized in that, The deployment rules described in S1 are specifically as follows: Following a bottom-up order, the permanent magnet synchronous motor windings are arranged in each winding layer within the pre-coded motor slot. If the total number of turns in the permanent magnet synchronous motor windings is odd, then based on expert experience, the number of turns in the first winding layer is set to odd, and the number of turns in the remaining winding layers is set to even. If the total number of turns in the permanent magnet synchronous motor windings is even, then based on expert experience, the number of turns in the first winding layer is set to even, and the number of turns in the remaining winding layers is also set to even.

3. The improved method for optimizing the winding of a permanent magnet synchronous motor according to claim 2, characterized in that, The improved segmented symmetrical rewinding strategy described in S2 specifically includes: S21: Obtain the number of winding turns in each winding layer of the winding distribution structure, and obtain the winding turn sequence table; S22: Based on the winding turn sequence table, wind each layer of winding sequentially, and perform the following steps for each layer of winding: S221: Determine the number of turns N of the winding in this layer; If the number of turns N is odd, then execute S222; if the number of turns N is even, then execute S224. S222: Determine the spatial arrangement order of the windings in this layer, and first wind the (N+1) / 2th turn winding located in the middle of the arrangement order in this layer and execute S223; S223: Using the middle winding as the center of symmetry, the remaining windings are wound alternately towards both ends of the layer; wherein, the two turns wound at each pair of symmetrical positions have opposite winding paths. S224: Determine the spatial arrangement order of the windings in this layer and their corresponding centerline positions. Using the centerline position as the center of symmetry, simultaneously wind all windings alternately towards both ends of this layer. Among them, the two turns of winding wound at each pair of symmetrical positions have opposite winding paths. After completing the winding of the m-th layer, the winding of the (m+1)-th layer is performed. Among them, the starting point of the winding of the (m+1)-th layer and the ending point of the winding of the m-th layer are spatially symmetrical with respect to the plane containing the central axis of the motor slot.

4. The improved method for optimizing the winding of a permanent magnet synchronous motor according to claim 3, characterized in that, It also includes constructing a lumped parasitic capacitance calculation model for permanent magnet synchronous motor windings based on the energy method, and obtaining the parasitic capacitance of the winding system based on the lumped parasitic capacitance calculation model; And the expression for the lumped parasitic capacitance calculation model is: In the formula: Represents lumped capacitance; This represents the potential difference between the first and last turns of each winding layer; This represents the total electric field energy after the windings in each winding layer of a permanent magnet synchronous motor are wound based on the winding distribution structure. This represents the capacitance between different turns; This represents the potential difference between different turns.

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