Rapid calculation method, device and equipment for electromagnetic noise of permanent magnet synchronous motor and medium

Abstract

The invention relates to a method, a device, equipment and a medium for quickly calculating electromagnetic noise of a permanent magnet synchronous motor, and the method is used for quickly and accurately calculating the electromagnetic noise of the permanent magnet synchronous motor with a rotor skewed pole, and specifically comprises the following steps: carrying out finite element modal simulation on a motor assembly according to a given motor geometric model and actual assembly and installation conditions; outputting motor structure modal parameters and a stator three-dimensional grid file, screening stator tooth surface grid nodes from the motor structure modal parameters and the stator three-dimensional grid file as target grid nodes, and numbering the target grid nodes; constructing a motor 2D transient electromagnetic field simulation analysis finite element model according to given motor electromagnetic parameters; performing electromagnetic force simulation on the motor 2D transient electromagnetic field simulation analysis finite element model according to a given motor operation condition; and in combination with a given rotor skewed pole angle and the obtained electromagnetic force simulation, obtaining electromagnetic forces of all stator tooth surface grid nodes, loading the electromagnetic forces to a finite element model of a motor assembly, and calculating electromagnetic vibration response of the motor and electromagnetic noise of the permanent magnet synchronous motor in sequence.

Description

Technical Field

[0001] This invention relates to the field of simulation and calculation technology of electromagnetic force and electromagnetic noise of electric motors, specifically to a method for rapid calculation of electromagnetic noise of permanent magnet synchronous motors, a corresponding device, electronic equipment, and a computer-readable storage medium. Background Technology

[0002] In recent years, the continuous iteration of new energy vehicle technology has driven its market share to gradually expand, and electric vehicles have gradually become the mainstream direction of the automotive market. As a core component of new energy vehicles, the motor inevitably generates electromagnetic noise during operation. With consumers' increasing demands for vehicle ride comfort, motor noise has become a common concern and an urgent problem for automakers. Rotor skew technology, as a key design approach, is widely used. By axially canceling the phase of electromagnetic forces, it can significantly reduce electromagnetic force waves and noise of a specific order. However, the introduction of rotor skew also causes the distribution of electromagnetic forces to exhibit complex changes along the axial direction, which greatly increases the difficulty of noise prediction. If the noise of drive motors with rotor skew can be calculated quickly, the development cycle can be significantly shortened and development costs reduced.

[0003] Currently, there are three main methods for calculating electromagnetic noise: analytical method, semi-analytical method, and finite element method. Analytical methods are based on mathematical calculations. First, electromagnetic force is calculated analytically according to electromagnetic field theory. Then, the motor is simplified, and electromagnetic noise is calculated based on the simplified casing under electromagnetic force excitation. Semi-analytical methods address the low accuracy of purely analytical methods by combining analytical methods with the finite element method (FEM). The FEM is used to calculate electromagnetic force or motor modal results, thus allowing for consideration of the influence of complex magnetic circuits and structures, improving calculation accuracy. Therefore, the calculation accuracy and efficiency of semi-analytical methods fall between those of analytical methods and the FEM. The finite element method uses commercial software to calculate electromagnetic noise. First, electromagnetic force is obtained through electromagnetic field simulation. Then, motor modal results are obtained through finite element modal simulation. Finally, the simulated electromagnetic force is applied to the motor structure, and electromagnetic vibration is calculated using modal superposition. Electromagnetic noise is then calculated using either the finite element method or the boundary element method.

[0004] Although the finite element method (FEM) offers high computational accuracy, in practical engineering applications, to simplify the calculation process or due to limitations in computational resources, an "integral equivalence" approach is commonly used when handling electromagnetic force loading. Specifically, this involves integrating the discrete electromagnetic forces distributed across the stator teeth surface of the motor, equating them to concentrated forces acting on the stator nodes, and then applying this concentrated force to the structural model for noise calculation. However, this simplification of distributed forces into concentrated forces alters the original spatial distribution characteristics of the electromagnetic forces, leading to significant calculation errors at high frequencies or in frequency bands sensitive to local structural vibrations. For motors employing skewed rotor technology, the axial distribution of electromagnetic forces is even more complex, and the simple integral equivalence approach further amplifies this error, resulting in distorted noise prediction results. Summary of the Invention

[0005] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for rapid calculation of electromagnetic noise of permanent magnet synchronous motors, a corresponding device, electronic equipment, and a computer-readable storage medium.

[0006] The technical solution of the present invention to solve the above-mentioned technical problems is: A method for rapid calculation of electromagnetic noise of a permanent magnet synchronous motor includes the following steps: S1. Based on the given motor geometric model and actual assembly and installation conditions, establish a finite element model of the motor assembly, define the material properties and boundary constraints of each component, perform finite element modal simulation on the motor assembly, and output the motor structural modal parameters and stator three-dimensional mesh file. S2. Read the stator 3D mesh file, filter the stator tooth surface mesh nodes as target mesh nodes, and number all target mesh nodes; S3: Based on the given electromagnetic parameters of the motor, construct a finite element model of the motor for 2D transient electromagnetic field simulation analysis in electromagnetic simulation software; S4. Based on the given motor operating conditions, perform electromagnetic force simulation on the finite element model of the motor's 2D transient electromagnetic field simulation analysis. S5. Combining the given rotor skew angle and the electromagnetic force simulation obtained in step S4, the electromagnetic force of all stator tooth mesh nodes distributed along the motor axis is obtained. S6. Apply the electromagnetic force of all stator tooth mesh nodes obtained in step S5 to the finite element model of the motor assembly established in step S1, calculate the electromagnetic vibration response of the motor using the modal superposition method, and then calculate the electromagnetic noise of the permanent magnet synchronous motor considering the rotor skew poles.

[0007] Preferably, the specific steps of step S1 are as follows: S11. Import the motor geometry model, mesh the stator, and set the arc length of the stator tooth mesh unit to x and the axial width to y. S12, assign corresponding material properties to the stator core, rotor core, permanent magnet, housing and winding respectively; apply bolt preload constraints, bearing support stiffness constraints and suspension fixing constraints according to the actual assembly and installation conditions; S13. Set the modal solution parameters, perform finite element modal simulation on the motor assembly, output the motor structure modal parameter file, and export the stator three-dimensional mesh file in UNV format.

[0008] Preferably, the specific steps of step S2 are as follows: S21. Use data processing software to read the UNV format stator 3D mesh file exported in step S1, parse and extract the spatial position coordinate information of each stator tooth surface mesh node; S22. Select stator tooth surface mesh nodes as target mesh nodes, and establish a numbering rule for the target mesh nodes to achieve numbering of all target mesh nodes. The numbering rule is as follows: Let the inner radius of the stator be R, then the inner circumference of the stator is 2πR, and the total axial length of the stator is L. Establish a two-dimensional numbering system with the starting point of the stator's axial direction as the origin, the axial direction as the Y-axis, and the arc direction as the X-axis, and number them according to the following rules: The first row corresponds to the axial coordinate 0, and its node numbers are (0,0), (0,x), (0,2x), ..., (0,2πR-x); The corresponding axial coordinate y is the 2nd row, and its node numbers are (y,0), (y,x), (y,2x), ..., (y,2πR-x); And so on; The last row corresponds to the axial coordinate L, and its node numbers are (L,0), (L,x), (L,2x), ..., (L,2πR-x) in sequence, realizing a unique correspondence between each 3D stator tooth surface node and the two-dimensional number.

[0009] Preferably, step S3 specifically includes the following steps: S31. Import the given motor geometry model into the electromagnetic simulation software JMAG. Based on the axial consistency and axial periodicity of the motor, only a 2D planar model of half a unit motor needs to be established. S32. Based on the given silicon steel sheet material parameters and permanent magnet material parameters, assign corresponding materials to the stator core, rotor core, and permanent magnet respectively; set the circuit excitation based on the given current parameters; S33. Set the motion boundary conditions of the rotor and the periodic boundary conditions of the model, set the solution steps and time steps of the transient simulation, and mesh the 2D planar model. The arc length of the stator tooth surface mesh is set to X to obtain the finite element model of transient electromagnetic field simulation of permanent magnet synchronous motor.

[0010] Preferably, step S4 specifically includes the following steps: S41. Select any speed point in the given operating conditions as the simulation speed point, and match the electromagnetic load conditions corresponding to that speed. S42. Start the transient electromagnetic field simulation. After the electromagnetic force simulation is completed, export the electromagnetic force simulation file containing the stator tooth surface mesh node numbers, positions and corresponding electromagnetic force information at the simulation speed point, in UNV format. S43. Use Matlab software to read the exported electromagnetic force simulation file and obtain the time-domain electromagnetic force experienced by each target grid node at the simulation rotation speed point.

[0011] Preferably, step S5 specifically includes the following steps: S51. The electromagnetic force data obtained from the electromagnetic force simulation of the finite element model of the 2D transient electromagnetic field simulation analysis of the motor is directly mapped to the stator tooth surface mesh nodes of the first row at the axial starting end of the finite element model of the motor assembly, as the initial electromagnetic force distribution. S52. Based on the given rotor skew angle, calculate the circumferential phase offset distance of the electromagnetic force wave as it travels one stroke along the axial direction. S53. Based on the circumferential phase offset distance, determine its corresponding position in the previous row; if the corresponding position is located between two adjacent known stator tooth surface grid nodes in the previous row, then use the electromagnetic force values ​​of these two adjacent stator tooth surface grid nodes to calculate the electromagnetic force of the current stator tooth surface grid node through a linear interpolation algorithm; during interpolation, determine the respective weight coefficients according to the relative position of the circumferential phase offset distance between the two adjacent stator tooth surface grid nodes. S54. Calculate row by row from the starting end to the end of the axial direction, determine the electromagnetic force values ​​of all stator tooth surface grid nodes in each row in turn, and finally reconstruct the three-dimensional electromagnetic force field distribution of the stator tooth surface considering the rotor skew pole effect.

[0012] Preferably, step S6 specifically includes the following steps: S61. Select a cylindrical coordinate system and set the origin of the coordinate system to coincide with the geometric center of the stator core. S62. Apply the electromagnetic force of all stator tooth mesh nodes to the target mesh nodes of the stator tooth surface of the motor assembly finite element model according to the node number. S63. Call the motor structure modal parameters output in step S1 and use the modal superposition method to solve the vibration response of the motor assembly under electromagnetic force excitation. S64. Based on the vibration response results, use the boundary element method or finite element method to perform acoustic simulation and calculate the electromagnetic noise radiated by the motor.

[0013] A device for rapid calculation of electromagnetic noise of a permanent magnet synchronous motor, comprising: The model building and modal analysis module is used to build a finite element model of the motor assembly based on the given motor geometric model and actual assembly and installation conditions, define the material properties and boundary constraints of each component, perform finite element modal simulation on the motor assembly, and output the motor structural modal parameters and stator 3D mesh file. The node processing module is used to read the stator 3D mesh file output by the model building and modal analysis module, select stator tooth surface mesh nodes as target mesh nodes, and uniformly number all target mesh nodes to form a set of numbered target mesh nodes. The electromagnetic field model building module is used to build a finite element model of the motor's 2D transient electromagnetic field simulation analysis in a preset electromagnetic simulation software based on the given electromagnetic parameters of the motor. The electromagnetic force simulation module is used to perform electromagnetic force simulation on the 2D transient electromagnetic field simulation analysis finite element model of the motor constructed by the electromagnetic field model construction module according to the given motor operating conditions, and output basic electromagnetic force data. The axial electromagnetic force distribution calculation module is used to combine the given rotor skew angle and the basic electromagnetic force data output by the electromagnetic force simulation module, and through skew effect equivalent calculation, obtain the stator tooth surface mesh node electromagnetic force distributed along the motor axis, which corresponds one-to-one with the numbered target mesh node in the node processing module. A vibration and noise calculation module is used to apply the electromagnetic forces of all stator tooth mesh nodes obtained by the axial electromagnetic force distribution calculation module to the finite element model of the motor assembly established by the model establishment and modal analysis module. The module uses the modal superposition method to calculate the electromagnetic vibration response of the motor, and calculates the electromagnetic noise of the permanent magnet synchronous motor considering rotor skewness based on the vibration response results. An electronic device includes a central processing unit and a memory. The central processing unit is used to call and run a computer program stored in the memory to execute the steps of the rapid calculation method for electromagnetic noise of the permanent magnet synchronous motor.

[0014] A computer-readable storage medium stores, in the form of computer-readable instructions, a computer program implemented according to the method for rapid calculation of electromagnetic noise of a permanent magnet synchronous motor, wherein the computer program, when called by a computer, executes the steps included in the corresponding method.

[0015] Compared with the prior art, the present invention has the following advantages: The rapid calculation method for electromagnetic noise of permanent magnet synchronous motors of the present invention can quickly obtain the electromagnetic force of the grid after rotor skew pole deflection and complete the corresponding electromagnetic noise calculation, thereby significantly reducing the calculation time and cost. It can achieve rapid and accurate prediction of electromagnetic noise in the early stage of motor noise optimization research and development, thereby effectively shortening the research and development cycle, greatly improving the calculation efficiency and research and development iteration capability, and providing efficient technical support for motor noise reduction optimization. Attached Figure Description

[0016] Figure 1 This is a structural block diagram of the method for rapid calculation of electromagnetic noise of permanent magnet synchronous motors according to the present invention. Detailed Implementation

[0017] The present invention will be further described in detail below with reference to the embodiments and accompanying drawings, but the embodiments of the present invention are not limited thereto.

[0018] Example 1 See Figure 1 The method for rapid calculation of electromagnetic noise of permanent magnet synchronous motor of the present invention includes the following steps: S1. Based on the given motor geometric model and actual assembly and installation conditions, establish a finite element model of the motor assembly, define the material properties and boundary constraints of each component, perform finite element modal simulation on the motor assembly, and output the motor structural modal parameters and stator 3D mesh file. The specific steps are as follows: S11. Import the motor geometry model, mesh the stator, and set the arc length of the stator tooth mesh unit to x and the axial width to y. S12, assign corresponding material properties to the stator core, rotor core, permanent magnet, housing and winding respectively; apply bolt preload constraints, bearing support stiffness constraints and suspension fixing constraints according to the actual assembly and installation conditions; S13. Set the modal solution parameters, perform finite element modal simulation on the motor assembly, output the motor structure modal parameter file, and export the stator three-dimensional mesh file in UNV format.

[0019] S2. Read the stator 3D mesh file, select stator tooth surface mesh nodes as target mesh nodes, and number all target mesh nodes. The specific steps are as follows: S21. Use data processing software to read the UNV format stator 3D mesh file exported in step S1, parse and extract the spatial position coordinate information of each stator tooth surface mesh node; S22. Select stator tooth surface mesh nodes as target mesh nodes, and establish a numbering rule for the target mesh nodes to achieve numbering of all target mesh nodes. The numbering rule is as follows: S21. Use data processing software to read the UNV format stator 3D mesh file exported in step S1, parse and extract the spatial position coordinate information of each stator tooth surface mesh node; S22. Select stator tooth surface mesh nodes as target mesh nodes, and establish a numbering rule for the target mesh nodes to achieve numbering of all target mesh nodes. The numbering rule is as follows: Let the inner radius of the stator be R, then the inner circumference of the stator is 2πR, and the total axial length of the stator is L. Establish a two-dimensional numbering system with the starting point of the stator's axial direction as the origin, the axial direction as the Y-axis, and the arc direction as the X-axis, and number them according to the following rules: The first row corresponds to the axial coordinate 0, and its node numbers are (0,0), (0,x), (0,2x), ..., (0,2πR-x); The corresponding axial coordinate y is the 2nd row, and its node numbers are (y,0), (y,x), (y,2x), ..., (y,2πR-x); And so on; The last row corresponds to the axial coordinate L, and its node numbers are (L,0), (L,x), (L,2x), ..., (L,2πR-x) in sequence, realizing a unique correspondence between each 3D stator tooth surface node and the two-dimensional number.

[0020] S3: Based on the given electromagnetic parameters of the motor, construct a finite element model of the motor for 2D transient electromagnetic field simulation analysis in electromagnetic simulation software. This includes the following steps: S31. Import the given motor geometry model into the electromagnetic simulation software JMAG. Based on the axial consistency and axial periodicity of the motor, only a 2D planar model of half a unit motor needs to be established. S32. Based on the given silicon steel sheet material parameters and permanent magnet material parameters, assign corresponding materials to the stator core, rotor core, and permanent magnet respectively; set the circuit excitation based on the given current parameters; S33. Set the motion boundary conditions of the rotor and the periodic boundary conditions of the model, set the solution steps and time steps of the transient simulation, and mesh the 2D planar model. The arc length of the stator tooth surface mesh is set to x to obtain the finite element model of transient electromagnetic field simulation of permanent magnet synchronous motor.

[0021] S4. Based on the given motor operating conditions, perform electromagnetic force simulation on the finite element model of the motor's 2D transient electromagnetic field simulation analysis. The specific steps are as follows: S41. Select any speed point in the given operating conditions as the simulation speed point, and match the electromagnetic load conditions corresponding to that speed. S42. Start the transient electromagnetic field simulation. After the electromagnetic force simulation is completed, export the electromagnetic force simulation file containing the stator tooth surface mesh node numbers, positions and corresponding electromagnetic force information at the simulation speed point, in UNV format. S43. Use Matlab software to read the exported electromagnetic force simulation file and obtain the time-domain electromagnetic force experienced by each target mesh node at the simulation rotation speed point.

[0022] S5. Combining the given rotor skew angle and the electromagnetic force simulation obtained in step S4, the electromagnetic force of all stator tooth mesh nodes distributed along the motor axis is obtained. The specific steps are as follows: Electromagnetic force data obtained from electromagnetic force simulation of the finite element model of the 2D transient electromagnetic field simulation analysis of the motor is directly mapped to the stator tooth surface mesh nodes of the first row at the axial starting end of the finite element model of the motor assembly, as the initial electromagnetic force distribution. Based on the given rotor skew angle, the circumferential phase offset distance of the electromagnetic force wave as it travels one row axially is calculated. Based on this circumferential phase offset distance, its corresponding position in the previous row is determined. If this corresponding position is located between two adjacent known stator tooth surface mesh nodes in the previous row, the electromagnetic force of the current stator tooth surface mesh node is calculated using the electromagnetic force values ​​of these two adjacent stator tooth surface mesh nodes through a linear interpolation algorithm. During interpolation, the weighting coefficients are determined according to the relative positions of the circumferential phase offset distances between two adjacent stator tooth surface mesh nodes. The calculation proceeds row by row from the axial starting end to the end, sequentially determining the electromagnetic force values ​​of all stator tooth surface mesh nodes in each row, ultimately reconstructing the three-dimensional electromagnetic force field distribution of the stator tooth surface considering the rotor skew effect.

[0023] In this embodiment, since the stator mesh length of the finite element model of the 2D transient electromagnetic field simulation analysis of the motor established in step S3 is the same as the stator mesh length of the finite element model of the motor assembly established in step S1, the electromagnetic force of each stator mesh node obtained by simulation in step S4 corresponds one-to-one with the first row of mesh nodes in the finite element model of the motor assembly. That is, the electromagnetic force of the mesh nodes numbered (0,0), (0,x), (0,2x), (0,3x), ..., (0,2πR-x) is known. Assuming the skew angle is β, the corresponding position of the grid node (0,0) in the second row is y×tanβ. Assuming mx≤y×tanβ≤(m+1)x, where m=0, 1, 2, ..., the electromagnetic force at the node (y,(m+1)x) in the second row is... The electromagnetic force can be obtained by interpolation from the electromagnetic forces of two grid nodes, (0,0) and (0,x). The specific calculation is as follows: ; In the formula: the electromagnetic forces of the two grid nodes (0,0) and (0,x) are respectively and ; Furthermore, the electromagnetic forces of the other grid nodes in the second row can be obtained by repeating the above process; the electromagnetic forces of each grid node in other rows can be obtained by the same method used to obtain the electromagnetic forces of each grid node in the second row.

[0024] S6. Apply the electromagnetic force of all stator tooth mesh nodes obtained in step S5 to the finite element model of the motor assembly established in step S1, calculate the electromagnetic vibration response of the motor using the modal superposition method, and then calculate the electromagnetic noise of the permanent magnet synchronous motor considering the rotor skew poles. The specific steps are as follows: S61. Select a cylindrical coordinate system and set the origin of the coordinate system to coincide with the geometric center of the stator core. S62. Apply the electromagnetic force of all stator tooth mesh nodes to the target mesh nodes of the stator tooth surface of the motor assembly finite element model according to the node number. S63. Call the motor structure modal parameters output in step S1 and use the modal superposition method to solve the vibration response of the motor assembly under electromagnetic force excitation. S64. Based on the vibration response results, use the boundary element method or finite element method to perform acoustic simulation and calculate the electromagnetic noise radiated by the motor.

[0025] Finally, the proposed method for rapid calculation of electromagnetic noise in permanent magnet synchronous motors considering rotor skew can efficiently and accurately obtain the electromagnetic force distribution at the grid level after rotor skew deflection, thereby quickly completing the quantitative calculation of electromagnetic noise in motors with rotor skew structures. This invention can significantly reduce calculation time and computing costs, breaking through the bottleneck of low efficiency in traditional calculation methods. It can achieve rapid prediction and accurate evaluation of electromagnetic noise in the early stages of motor noise optimization research and development, thereby effectively shortening the overall motor development cycle and significantly improving the calculation efficiency and optimization iteration speed in the research and development process. This provides core technical support for rapid product launch and seizing market opportunities, and also lays a solid foundation for the accurate formulation of subsequent noise optimization schemes, combining technical practicality and economic value.

[0026] Example 2 The permanent magnet synchronous motor electromagnetic noise rapid calculation device of the present invention includes: The model building and modal analysis module is used to build a finite element model of the motor assembly based on the given motor geometric model and actual assembly and installation conditions, define the material properties and boundary constraints of each component, perform finite element modal simulation on the motor assembly, and output the motor structural modal parameters and stator 3D mesh file. The node processing module is used to read the stator 3D mesh file output by the model building and modal analysis module, select stator tooth surface mesh nodes as target mesh nodes, and uniformly number all target mesh nodes to form a set of numbered target mesh nodes. The electromagnetic field model building module is used to build a finite element model of the motor's 2D transient electromagnetic field simulation analysis in a preset electromagnetic simulation software based on the given electromagnetic parameters of the motor. The electromagnetic force simulation module is used to perform electromagnetic force simulation on the 2D transient electromagnetic field simulation analysis finite element model of the motor constructed by the electromagnetic field model construction module according to the given motor operating conditions, and output basic electromagnetic force data. The axial electromagnetic force distribution calculation module is used to combine the given rotor skew angle and the basic electromagnetic force data output by the electromagnetic force simulation module, and through skew effect equivalent calculation, obtain the stator tooth surface mesh node electromagnetic force distributed along the motor axis, which corresponds one-to-one with the numbered target mesh node in the node processing module. The vibration and noise calculation module is used to load the electromagnetic forces of all stator tooth mesh nodes obtained by the axial electromagnetic force distribution calculation module onto the finite element model of the motor assembly established by the model establishment and modal analysis module, calculate the electromagnetic vibration response of the motor using the modal superposition method, and calculate the electromagnetic noise of the permanent magnet synchronous motor considering the rotor skew poles based on the vibration response results.

[0027] Example 3 The electronic device of the present invention includes a central processing unit and a memory, wherein the central processing unit is used to call and run a computer program stored in the memory to execute the steps of the method for rapid calculation of electromagnetic noise of a permanent magnet synchronous motor.

[0028] Example 4 The computer-readable storage medium of the present invention stores, in the form of computer-readable instructions, a computer program implemented according to the method for rapid calculation of electromagnetic noise of a permanent magnet synchronous motor, which, when called by a computer, executes the steps included in the corresponding method.

[0029] The above are preferred embodiments of the present invention, but the embodiments of the present invention are not limited to the above content. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.

Claims

1. A method for rapid calculation of electromagnetic noise of a permanent magnet synchronous motor, characterized in that, Includes the following steps: S1. Based on the given motor geometric model and actual assembly and installation conditions, establish a finite element model of the motor assembly, define the material properties and boundary constraints of each component, perform finite element modal simulation on the motor assembly, and output the motor structural modal parameters and stator three-dimensional mesh file. S2. Read the stator 3D mesh file, filter the stator tooth surface mesh nodes as target mesh nodes, and number all target mesh nodes; S3: Based on the given electromagnetic parameters of the motor, construct a finite element model of the motor for 2D transient electromagnetic field simulation analysis in electromagnetic simulation software; S4. Based on the given motor operating conditions, perform electromagnetic force simulation on the finite element model of the motor's 2D transient electromagnetic field simulation analysis. S5. Combining the given rotor skew angle and the electromagnetic force simulation obtained in step S4, the electromagnetic force of all stator tooth mesh nodes distributed along the motor axis is obtained. S6. Apply the electromagnetic force of all stator tooth mesh nodes obtained in step S5 to the finite element model of the motor assembly established in step S1, calculate the electromagnetic vibration response of the motor using the modal superposition method, and then calculate the electromagnetic noise of the permanent magnet synchronous motor considering the rotor skew poles.

2. The method for rapid calculation of electromagnetic noise of a permanent magnet synchronous motor according to claim 1, characterized in that, The specific steps of step S1 are as follows: S11. Import the motor geometry model, mesh the stator, and set the arc length of the stator tooth mesh unit to x and the axial width to y. S12, assign corresponding material properties to the stator core, rotor core, permanent magnet, housing and winding respectively; apply bolt preload constraints, bearing support stiffness constraints and suspension fixing constraints according to the actual assembly and installation conditions; S13. Set the modal solution parameters, perform finite element modal simulation on the motor assembly, output the motor structure modal parameter file, and export the stator three-dimensional mesh file in UNV format.

3. The method for rapid calculation of electromagnetic noise of a permanent magnet synchronous motor according to claim 2, characterized in that, The specific steps of step S2 are as follows: S21. Use data processing software to read the UNV format stator 3D mesh file exported in step S1, parse and extract the spatial position coordinate information of each stator tooth surface mesh node; S22. Select stator tooth surface mesh nodes as target mesh nodes, and establish a numbering rule for the target mesh nodes to achieve numbering of all target mesh nodes. The numbering rule is as follows: Let the inner radius of the stator be R, then the inner circumference of the stator is 2πR, and the total axial length of the stator is L. Establish a two-dimensional numbering system with the starting point of the stator's axial direction as the origin, the axial direction as the Y-axis, and the arc direction as the X-axis, and number them according to the following rules: The first row corresponds to the axial coordinate 0, and its node numbers are (0,0), (0,x), (0,2x), ..., (0,2πR-x); The corresponding axial coordinate y is the 2nd row, and its node numbers are (y,0), (y,x), (y,2x), ..., (y,2πR-x); And so on; The last row corresponds to the axial coordinate L, and its node numbers are (L,0), (L,x), (L,2x), ..., (L,2πR-x) in sequence, realizing a unique correspondence between each 3D stator tooth surface node and the two-dimensional number.

4. The method for rapid calculation of electromagnetic noise of a permanent magnet synchronous motor according to claim 3, characterized in that, Step S3 specifically includes the following steps: S31. Import the given motor geometry model into the electromagnetic simulation software JMAG. Based on the axial consistency and axial periodicity of the motor, only a 2D planar model of half a unit motor needs to be established. S32. Based on the given silicon steel sheet material parameters and permanent magnet material parameters, assign corresponding materials to the stator core, rotor core, and permanent magnet respectively; set the circuit excitation based on the given current parameters; S33. Set the motion boundary conditions of the rotor and the periodic boundary conditions of the model, set the solution steps and time steps of the transient simulation, and mesh the 2D planar model. The arc length of the stator tooth surface mesh is set to X to obtain the finite element model of transient electromagnetic field simulation of permanent magnet synchronous motor.

5. The method for rapid calculation of electromagnetic noise of a permanent magnet synchronous motor according to claim 4, characterized in that, Step S4 specifically includes the following steps: S41. Select any speed point in the given operating conditions as the simulation speed point, and match the electromagnetic load conditions corresponding to that speed. S42. Start the transient electromagnetic field simulation. After the electromagnetic force simulation is completed, export the electromagnetic force simulation file containing the stator tooth surface mesh node numbers, positions and corresponding electromagnetic force information at the simulation speed point, in UNV format. S43. Use Matlab software to read the exported electromagnetic force simulation file and obtain the time-domain electromagnetic force experienced by each target grid node at the simulation rotation speed point.

6. The method for rapid calculation of electromagnetic noise of a permanent magnet synchronous motor according to claim 5, characterized in that, Step S5 specifically includes the following steps: S51. The electromagnetic force data obtained from the electromagnetic force simulation of the finite element model of the 2D transient electromagnetic field simulation analysis of the motor is directly mapped to the stator tooth surface mesh nodes of the first row at the axial starting end of the finite element model of the motor assembly, as the initial electromagnetic force distribution. S52. Based on the given rotor skew angle, calculate the circumferential phase offset distance of the electromagnetic force wave as it travels one stroke along the axial direction. S53. Based on the circumferential phase offset distance, determine its corresponding position in the previous row; if the corresponding position is located between two adjacent known stator tooth surface grid nodes in the previous row, then use the electromagnetic force values ​​of these two adjacent stator tooth surface grid nodes to calculate the electromagnetic force of the current stator tooth surface grid node through a linear interpolation algorithm; during interpolation, determine the respective weight coefficients according to the relative position of the circumferential phase offset distance between the two adjacent stator tooth surface grid nodes. S54. Calculate row by row from the starting end to the end of the axial direction, determine the electromagnetic force values ​​of all stator tooth surface grid nodes in each row in turn, and finally reconstruct the three-dimensional electromagnetic force field distribution of the stator tooth surface considering the rotor skew pole effect.

7. The method for rapid calculation of electromagnetic noise of a permanent magnet synchronous motor according to claim 6, characterized in that, Step S6 specifically includes the following steps: S61. Select a cylindrical coordinate system and set the origin of the coordinate system to coincide with the geometric center of the stator core. S62. Apply the electromagnetic force of all stator tooth mesh nodes to the target mesh nodes of the stator tooth surface of the motor assembly finite element model according to the node number. S63. Call the motor structure modal parameters output in step S1 and use the modal superposition method to solve the vibration response of the motor assembly under electromagnetic force excitation. S64. Based on the vibration response results, use the boundary element method or finite element method to perform acoustic simulation and calculate the electromagnetic noise radiated by the motor.

8. A device for rapidly calculating the electromagnetic noise of a permanent magnet synchronous motor, characterized in that, include: The model building and modal analysis module is used to build a finite element model of the motor assembly based on the given motor geometric model and actual assembly and installation conditions, define the material properties and boundary constraints of each component, perform finite element modal simulation on the motor assembly, and output the motor structural modal parameters and stator 3D mesh file. The node processing module is used to read the stator 3D mesh file output by the model building and modal analysis module, select stator tooth surface mesh nodes as target mesh nodes, and uniformly number all target mesh nodes to form a set of numbered target mesh nodes. The electromagnetic field model building module is used to build a finite element model of the motor's 2D transient electromagnetic field simulation analysis in a preset electromagnetic simulation software based on the given electromagnetic parameters of the motor. The electromagnetic force simulation module is used to perform electromagnetic force simulation on the 2D transient electromagnetic field simulation analysis finite element model of the motor constructed by the electromagnetic field model construction module according to the given motor operating conditions, and output basic electromagnetic force data. The axial electromagnetic force distribution calculation module is used to combine the given rotor skew angle and the basic electromagnetic force data output by the electromagnetic force simulation module, and through skew effect equivalent calculation, obtain the stator tooth surface mesh node electromagnetic force distributed along the motor axis, which corresponds one-to-one with the numbered target mesh node in the node processing module. The vibration and noise calculation module is used to load the electromagnetic forces of all stator tooth mesh nodes obtained by the axial electromagnetic force distribution calculation module onto the finite element model of the motor assembly established by the model establishment and modal analysis module, calculate the electromagnetic vibration response of the motor using the modal superposition method, and calculate the electromagnetic noise of the permanent magnet synchronous motor considering the rotor skew poles based on the vibration response results.

9. An electronic device comprising a central processing unit and a memory, characterized in that, The central processing unit is used to call and run a computer program stored in the memory to perform the steps of the method for rapid calculation of electromagnetic noise of permanent magnet synchronous motor as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, It stores in the form of computer-readable instructions a computer program implementing the method for rapid calculation of electromagnetic noise of a permanent magnet synchronous motor according to any one of claims 1 to 7. When the computer program is called and run by a computer, it executes the steps included in the corresponding method.

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