Axial motor hybrid analysis method and device based on two-dimensional finite element

Abstract

The invention relates to the technical field of motors, and discloses an axial motor hybrid analysis method and device based on a two-dimensional finite element, and the method comprises the steps: building an equivalent model at the average radius of an axial motor; obtaining initial electromagnetic performance parameters based on the equivalent model at the average radius of the axial motor; the saturation effect and the 3D effect of the motor are calculated through an analytical method, and a correction coefficient is obtained through calculation; and correcting the initial electromagnetic performance parameter by using the correction coefficient. According to the method, an analytical model is introduced, the specific three-dimensional effect, edge effect and iron core saturation difference of the axial motor are effectively considered, correction coefficients of flux linkage, back electromotive force and torque are provided, a two-dimensional finite element calculation result is subjected to system correction, and calculation errors are remarkably reduced; and on the basis of keeping the efficient calculation advantage of the two-dimensional finite element method, the simulation precision is greatly improved.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and specifically to a hybrid analytical method and apparatus for axial motors based on two-dimensional finite element method. Background Technology

[0002] Axial motors are motor topologies where the magnetic field direction is parallel to the axis of rotation. Thanks to their unique disc-shaped design, they offer higher power and torque compared to traditional radial motors under the same flat shape constraints. They also boast significant advantages such as high efficiency, excellent heat dissipation, and a compact structure. With advancements in motor technology and manufacturing processes, the bottlenecks restricting axial flux motors have been effectively resolved. In recent years, driven by the strong demand for extreme power density in fields such as electric vehicles, eVTOL, and aerospace, and combined with the development of new materials and advanced control technologies, axial motor technology is ushering in a golden age of commercial application, becoming a core direction for next-generation high-performance electric drive systems.

[0003] The design and analysis of existing axial motors has long been hampered by the trade-off between computational efficiency and simulation accuracy, making it difficult to quickly and accurately obtain electromagnetic performance, which severely restricts the optimization and iteration of motors. Therefore, developing a highly efficient analysis method that can balance efficiency and accuracy to overcome the above-mentioned technical bottlenecks and lower the design threshold has become a key issue that urgently needs to be addressed in the field of axial motors. Summary of the Invention

[0004] This invention provides a hybrid analytical method and apparatus for axial motors based on two-dimensional finite element method, in order to solve the long-standing problem of the contradiction between computational efficiency and simulation accuracy in the design and analysis of existing axial motors.

[0005] In a first aspect, the present invention provides a hybrid analytical method for axial motors based on two-dimensional finite element method. The method includes: establishing an equivalent model at the average radius of the axial motor; obtaining initial electromagnetic performance parameters based on the equivalent model at the average radius of the axial motor; calculating the saturation effect and 3D effect of the motor through analytical method, and calculating correction coefficients; and correcting the initial electromagnetic performance parameters using the correction coefficients.

[0006] This invention introduces an analytical model to effectively account for the unique three-dimensional effects, edge effects, and core saturation differences of axial motors. It proposes correction coefficients for flux linkage, back EMF, and torque, systematically correcting the two-dimensional finite element calculation results and significantly reducing calculation errors. This method, while maintaining the high efficiency of the two-dimensional finite element method, greatly improves simulation accuracy. Comparison with three-dimensional finite element results shows that this method significantly improves computational efficiency while ensuring accuracy, providing an effective means for the rapid and accurate design and performance optimization of axial motors.

[0007] In one alternative implementation, the initial electromagnetic performance parameters include: magnetic flux linkage, back electromotive force, and electromagnetic torque.

[0008] In one optional implementation, the process of establishing an equivalent model at the average radius of the axial motor includes: taking an annular cross-section at the average radius of the motor; unfolding the annular cross-section to obtain a two-dimensional model of the permanent magnet linear motor; the mover velocity of the two-dimensional model of the permanent magnet linear motor is the linear velocity at the average radius of the three-dimensional model; and converting the electric thrust calculated from the two-dimensional model into electromagnetic torque.

[0009] In one optional implementation, the process of calculating the flux correction coefficient includes: integrating the fundamental amplitude of the air gap flux density at different radii of the axial motor to obtain the fundamental air gap flux of the axial motor; calculating the fundamental air gap flux of the equivalent model at the average radius; and using the ratio of the fundamental air gap flux of the axial motor to the fundamental air gap flux as the flux correction coefficient.

[0010] In one optional implementation, the process of obtaining the fundamental amplitude of the air gap magnetic flux density at different radii of the axial motor includes: calculating the magnetic pole width at different radii based on the width of the permanent magnet at the inner and outer diameters and the length of the inner and outer radii; calculating the span angle of the permanent magnet at different radii and the pole arc coefficient that varies with the radius based on the magnetic pole width at different radii; approximating the no-load air gap magnetic flux density distribution of the motor to a square wave with a preset amplitude, and after Fourier series decomposition of the pole arc coefficient that varies with the radius, combining it with the edge effect correction function to obtain the fundamental amplitude of the air gap magnetic flux density at different radii of the axial motor.

[0011] In one optional implementation, for a surface-mounted permanent magnet axial motor, the process of calculating the electromagnetic torque correction coefficient includes: deriving the electromagnetic torque correction coefficient through an electromagnetic torque calculation formula based on the integral relationship between permanent magnet flux linkage and permanent magnet flux density, combined with the fundamental amplitude of permanent magnet flux density and the amplitude of permanent magnet flux density under core saturation.

[0012] In one optional implementation, the process of obtaining the permanent magnet flux density amplitude under core saturation conditions includes: calculating the fundamental air gap flux density amplitude at the average radius under the current load condition using two-dimensional finite element simulation data; calculating the flux density of the permanent magnet and the stator core at the current radius position through flux density integration; obtaining the core permeability corresponding to the current core flux density by interpolation calculation based on the flux density of the permanent magnet and the stator core at the current radius position, combined with the flux density-magnetic field strength relationship curve of the core material; and determining the core permeability based on the current core flux density at the current radius position. Based on the geometric dimensions and core permeability, the magnetic reluctance of each part in the motor magnetic circuit at the radial position is calculated. The difference between the calculated total magnetomotive force and the preset average magnetomotive force is compared. If the absolute value of the difference between the total magnetomotive force and the preset average magnetomotive force is less than the set error threshold, it is determined that the air gap magnetic flux density iteration at the current radius has converged, the iteration is stopped, and the final fundamental amplitude of the air gap magnetic flux density at the current radius and the corresponding permanent magnet magnetic flux density amplitude are recorded. The magnetic reluctance of each part is calculated, and the permanent magnet magnetic flux density amplitude at the current radius is calculated according to the magnetic circuit method. This permanent magnet magnetic flux density amplitude is the permanent magnet magnetic flux density amplitude under core saturation conditions.

[0013] Secondly, the present invention provides a hybrid analytical device for an axial motor based on two-dimensional finite element method. The device includes: a model building module for building an equivalent model at the average radius of the axial motor; an acquisition module for acquiring initial electromagnetic performance parameters based on the equivalent model at the average radius of the axial motor; a calculation module for calculating the saturation effect and 3D effect of the motor through analytical methods and calculating correction coefficients; and a correction module for correcting the initial electromagnetic performance parameters using the correction coefficients.

[0014] Thirdly, the present invention provides an electronic device, comprising: a memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to perform the above-described first aspect or any corresponding embodiment of the axial motor hybrid analysis method based on two-dimensional finite element method.

[0015] Fourthly, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to execute the two-dimensional finite element-based hybrid analytical method for axial motors described in the first aspect or any corresponding embodiment thereof.

[0016] Fifthly, the present invention provides a computer program product, including computer instructions for causing a computer to execute the two-dimensional finite element-based hybrid analytical method for axial motors described in the first aspect or any corresponding embodiment thereof. Attached Figure Description

[0017] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific 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.

[0018] Figure 1 This is a schematic diagram of an application scenario according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the first step of the hybrid analytical method for axial motors based on two-dimensional finite element method according to an embodiment of the present invention. Figure 3 This is a two-dimensional model of a permanent magnet linear motor according to an embodiment of the present invention; Figure 4 This is a schematic diagram of setting master-slave boundary conditions on both sides of the equivalent model according to an embodiment of the present invention; Figure 5 This is a correction curve for the edge effect according to an embodiment of the present invention; Figure 6 This is an equivalent magnetic circuit model according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the iterative process according to an embodiment of the present invention; Figure 8 This is a schematic diagram of the hardware structure of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0019] 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.

[0020] It is understood that before using the technical solutions disclosed in the various embodiments of the present invention, users should be informed of the types, scope of use, and usage scenarios of the personal information involved in the present invention and their authorization should be obtained in accordance with relevant laws and regulations through appropriate means.

[0021] As an optional application scenario of this invention, such as Figure 1 As shown, application 101 is installed in terminal device 110, and user 130 can interact with application 101 through terminal device 110 and / or access device of terminal device 110.

[0022] For example, application 101 can be any application that provides question-and-answer related services. For instance, application 101 could be a question-and-answer interactive application, such as a text-to-text application, an image-to-text application, etc. Figure 1 In the application scenario shown, if application 101 is active, the terminal device 110 can display the interface 102 of application 101. The interface 102 may include various pages that application 101 can provide, such as interactive pages, settings pages, query pages, etc.

[0023] In some embodiments, terminal device 110 is communicatively connected to server 120 to provide services to application 101. Terminal device 110 may be a mobile terminal, fixed terminal, or portable terminal, etc., including but not limited to mobile phones, desktop computers, laptop computers, multimedia tablets, e-book devices, gaming devices, or any combination thereof, including accessories and peripherals of these devices or any combination thereof. In some embodiments, terminal device 110 may also support any type of interface, and server 120 may be various types of computing systems or servers capable of providing computing power, including but not limited to mainframes, edge computing nodes, computing devices in cloud environments, etc.

[0024] It should be noted that, Figure 1 This is merely an example of an application scenario and does not limit the scope of protection of this invention.

[0025] The embodiments of the present invention will now be described with reference to the accompanying drawings. It should be understood that the pages shown in the drawings are merely examples, and various page designs are possible in practice. The various graphic elements on the page may have different arrangements and different visual representations; one or more elements may be omitted or replaced, and one or more other elements may also be present, without any limitation in the embodiments of the present invention. Furthermore, the embodiments described below primarily pertain to terminal device 110. It should be understood that the actions described relative to terminal device 110 can be performed by application 101 on terminal device 110, or can be performed by application 101 in conjunction with its server (e.g., server 120).

[0026] Defects and shortcomings of existing technology: 1. Existing three-dimensional (3D) finite element analysis places stringent requirements on computer hardware configurations such as CPU and memory, resulting in high hardware costs. Furthermore, to meet computational accuracy requirements, mesh density often needs to be increased, which causes computation time to increase exponentially, making the simulation of a single electrical cycle often take several hours, severely restricting the optimization and iteration of motors.

[0027] 2. Current methods for calculating the electromagnetic performance of axial motors based on two-dimensional (2D) finite element methods typically treat them as equivalent linear motors at the average radius, performing two-dimensional planar simulations. However, this method fails to adequately consider the unique three-dimensional effects, edge effects, and saturation differences of the core at different radial positions of axial motors, resulting in inherent biases in the electromagnetic performance calculations. Furthermore, this bias is exacerbated by increasing load current.

[0028] According to an embodiment of the present invention, a hybrid analytical method for axial motors based on two-dimensional finite element method is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0029] This embodiment provides a hybrid analytical method for axial motors based on two-dimensional finite element method, which can be used in the aforementioned mobile terminals, such as mobile phones and tablets. Figure 2 This is a flowchart of a hybrid analytical method for axial motors based on two-dimensional finite element method according to an embodiment of the present invention, as shown below. Figure 2 As shown, the process includes the following steps: Step S1: Establish an equivalent model at the average radius of the axial motor.

[0030] Optionally, the process of establishing an equivalent model at the average radius of the axial motor includes: taking an annular section at the average radius of the motor; unfolding the annular section to obtain a two-dimensional model of the permanent magnet linear motor; the mover velocity of the two-dimensional model of the permanent magnet linear motor is the linear velocity at the average radius of the three-dimensional model; and converting the electric thrust calculated from the two-dimensional model into electromagnetic torque.

[0031] like Figure 3 As shown, at the average radius of the motor R av Take a ring-shaped cross-section at a certain point, and unfold the cross-section to obtain a two-dimensional model of the permanent magnet linear motor. For example... Figure 4 As shown. Master-slave boundary conditions are set on both sides of the equivalent model to eliminate the edge effect of the linear motor.

[0032] To ensure simulation analysis under the same operating conditions, the simulation parameters of the 2D model need to be calculated using the parameters of the 3D model. The mover velocity of the 2D model is the linear velocity at the average radius of the 3D model. (1) Where v (rpm) is the motor speed. The electric thrust calculated from the 2D model needs to be converted into electromagnetic torque, which is: (2) Step S2: Obtain the initial electromagnetic performance parameters based on the equivalent model at the average radius of the axial motor.

[0033] Optionally, a professional electromagnetic finite element simulation software (such as Maxwell) can be used to load an equivalent two-dimensional model and set two core operating conditions corresponding to the actual operation of the axial motor: no-load condition (no armature current input, only the permanent magnet generates a magnetic field) and load condition (the rated armature current is input to simulate the motor's load operation state), ensuring that the simulation covers the main operating scenarios of the motor.

[0034] Optionally, the initial electromagnetic performance parameters include: magnetic flux linkage, back electromotive force, and electromagnetic torque.

[0035] Specifically, under two operating conditions, the key electromagnetic performance parameters of the axial motor were simulated, calculated, and recorded, including: (1) Magnetic flux: The magnetic flux value generated by the combined magnetic field of the permanent magnet and the magnetic field of the armature in the armature winding reflects the degree of coupling between the motor magnetic field and the winding.

[0036] (2) Back EMF: The induced electromotive force generated when the armature winding cuts the magnetic field of the permanent magnet when the motor rotates is the core indicator for evaluating the motor's energy conversion efficiency.

[0037] (3) Electromagnetic torque: The effective torque output by the motor directly determines the driving capability of the motor. Torque data under load conditions is a key reference for motor performance optimization.

[0038] (4) Air gap magnetic flux density: The magnetic field density distribution in the air gap region (the gap between the permanent magnet and the stator core) provides basic data for subsequent analysis of 3D effect and edge effect.

[0039] Step S3: Calculate the saturation effect and 3D effect of the motor using analytical methods, and obtain the correction coefficient.

[0040] Step S4: Correct the initial electromagnetic performance parameters using correction factors.

[0041] Optionally, the process of obtaining the fundamental amplitude of the air gap magnetic flux density at different radii of the axial motor includes: calculating the magnetic pole width at different radii based on the width of the permanent magnet at the inner and outer diameters and the length of the inner and outer radii; calculating the span angle of the permanent magnet at different radii and the pole arc coefficient that varies with the radius based on the magnetic pole width at different radii; approximating the no-load air gap magnetic flux density distribution of the motor to a square wave with a preset amplitude, and after Fourier series decomposition of the pole arc coefficient that varies with the radius, combining it with the edge effect correction function to obtain the fundamental amplitude of the air gap magnetic flux density at different radii of the axial motor.

[0042] Specifically, the topology of the axial motor determines that its air gap magnetic flux density is asymmetrically distributed radially, with variations at different radii. Ignoring the influence of stator slots on the air gap magnetic flux density, the radial distribution of the air gap magnetic flux density is primarily determined by the shape of the permanent magnet poles. A schematic diagram of a single pole of an AFPM motor is shown below. Figure 3 As shown. Among them w i , w o , R i , R o These represent the width of the permanent magnet at the inner and outer diameters, and the length of the inner and outer radii, respectively. For tile-shaped magnetic poles of arbitrary shape, different radii... r The width of the magnetic pole at that point can be expressed as: (3) The span angle of the permanent magnet at different radii is: (4) The polar arc coefficient, which varies with radius, is: (5) The no-load air gap magnetic flux density distribution of the motor approximates a square wave with amplitude Bm. After Fourier series decomposition, the fundamental amplitude of the air gap magnetic flux density, which varies with the radius, is: (6) λ ( r The function is the edge effect correction function. Through three-dimensional finite element simulation, the air gap magnetic flux density at the radial magnetic pole centerline is obtained. After standardization, the edge effect correction curve is obtained. Figure 5 As shown, the air gap magnetic flux density decreases rapidly at the edges of the inner and outer diameters. The edge effect is particularly pronounced for motors with smaller inner and outer diameters.

[0043] Edge effect correction function It can be represented in segments as follows: (7) The parameter 'a' can be determined by the air gap length. g and the thickness of the permanent magnet h m Represented as: (8) Among them, coefficient ξ 1~ ξ The values ​​for 5 are 2.194, -1.061, -0.105, 0.232, and 0.006, respectively.

[0044] Optionally, the process of calculating the flux correction coefficient includes: integrating the fundamental amplitude of the air gap flux density at different radii of the axial motor to obtain the fundamental air gap flux of the axial motor; calculating the fundamental air gap flux of the equivalent model at the average radius; and using the ratio of the fundamental air gap flux of the axial motor to the fundamental air gap flux as the flux correction coefficient.

[0045] Specifically, given the known amplitude of the air gap magnetic flux density, the fundamental amplitude of the air gap magnetic flux density at different radii of the axial motor can be calculated through the above analysis. Therefore, the fundamental magnetic flux density of the air gap of the axial motor is: (9) The air gap fundamental flux of the equivalent LSPM motor at the average radius is: (10) Then the inherent error correction coefficient of magnetic flux K f for: (11) The relationship between the magnetic flux linkage, back electromotive force, and air gap flux of the motor is as follows: (12) In the formula, N c This represents the effective number of turns. Since both flux linkage and back electromotive force are linearly related to magnetic flux, their correction factors can be used. K f The accurate result can be obtained by multiplying the two-dimensional finite element simulation result by the correction factor.

[0046] Optionally, for surface-mounted permanent magnet axial motors, the process of calculating the electromagnetic torque correction coefficient includes: deriving the electromagnetic torque correction coefficient through the electromagnetic torque calculation formula based on the integral relationship between permanent magnet flux linkage and permanent magnet flux density, combined with the fundamental amplitude of permanent magnet flux density and the amplitude of permanent magnet flux density under core saturation.

[0047] Specifically, for a surface-mounted permanent magnet motor, its electromagnetic torque is: (13) in, ψ m For a permanent magnet flux linkage, it can be solved using the permanent magnet flux density integral. Then the correction coefficient for the electromagnetic torque is... K t for: (14) in, B mg1 The amplitude of the fundamental magnetic flux density of the permanent magnet can be calculated using a simple magnetic circuit.

[0048] Optionally, the process of obtaining the permanent magnet flux density amplitude under core saturation includes: (1) Using two-dimensional finite element simulation data, calculate the fundamental air gap magnetic flux density amplitude at the average radius under the current load condition; (2) Calculate the magnetic flux density of the permanent magnet and the magnetic flux density of the stator core at the current radius position by performing magnetic flux density integration. (3) Based on the magnetic flux density of the permanent magnet and the magnetic flux density of the stator core at the current radius position, and combined with the magnetic flux density-magnetic field strength relationship curve of the core material, the permeability of the core corresponding to the current core magnetic flux density is obtained by interpolation calculation. (4) Based on the motor geometry and core permeability at the current radius, calculate the magnetic reluctance of each part of the motor magnetic circuit at this radial position; (5) Compare the difference between the calculated total magnetomotive force and the preset average magnetomotive force: If the absolute value of the difference between the total magnetomotive force and the preset average magnetomotive force is less than the set error threshold, it is determined that the air gap magnetic flux density iteration at the current radius has converged, the iteration is stopped, and the final air gap magnetic flux density fundamental amplitude value and the corresponding permanent magnet magnetic flux density amplitude value at the current radius are recorded. (6) Calculate the magnetic resistance of each part, and calculate the permanent magnet flux density amplitude under the current radius according to the magnetic circuit method. The permanent magnet flux density amplitude is the permanent magnet flux density amplitude under the condition of iron core saturation.

[0049] Specifically, the AFPM motor is divided into countless slices along the radial direction, and an equivalent magnetic circuit model is established, such as... Figure 6 As shown, the magnetic reluctance of the magnetic circuit varies at different radii, but the permanent magnet magnetomotive force and armature magnetomotive force are the same, resulting in different core saturation levels at different radii, and consequently, different air gap magnetic flux density. Based on the 2D finite element simulation results at the average radius, the air gap magnetic flux density was calculated using an iterative method. B g1 ( r Furthermore, based on the iterative calculation results, the amplitude of the permanent magnet flux density under core saturation conditions was calculated. B mg ( r The specific process is as follows: Figure 7 As shown.

[0050] In some optional implementations, the parsing method of this embodiment includes: (1) Establish an equivalent model of the axial motor at the average radius in the 2D plane, such as Figure 4 As shown. Master-slave boundary conditions are set on both sides of the equivalent model to eliminate the edge effect of the linear motor.

[0051] (2) Simulate and analyze the electromagnetic performance of the axial motor under no-load and load conditions, such as magnetic flux density, magnetic flux linkage, back electromotive force and electromagnetic torque, in Maxwell finite element software.

[0052] (3) Based on the geometric dimensions of the motor, establish as follows: Figure 5 The equivalent magnetic circuit model that varies with radius.

[0053] (4) Perform Fourier decomposition on the magnetic flux density in step (2) to calculate the fundamental magnetic flux density amplitude. Using the fundamental magnetic flux density amplitude at the average radius, through... Figure 7 The program flow graph is used to calculate the fundamental wave amplitude of the air gap magnetic flux density and the maximum value of the permanent magnet magnetic flux density at different radii.

[0054] (5) Substitute the air gap magnetic flux density into equation (11) to calculate the correction coefficients for the magnetic flux linkage and back electromotive force. K f .

[0055] (6) Calculate the fundamental amplitude of the permanent magnet flux density using equations (3)-(5), and substitute it into equation (14) to calculate the torque correction coefficient. K t .

[0056] (7) The calculated correction coefficient K f 、K t Multiply the flux linkage, back electromotive force and torque obtained in step (2) respectively to obtain the corrected equivalent result.

[0057] While the 3D finite element method (FEM) offers high computational accuracy for analyzing the electromagnetic performance of axial motors, it is extremely time-consuming and inefficient, hindering motor design optimization. This invention, based on a 2D equivalent model of the axial motor, utilizes the 2D finite element method for simulation analysis, significantly improving computational efficiency. Table 1 compares the computational speed of the 3D finite element method and this invention over one electrical cycle under no-load and loaded conditions. It can be seen that the computational efficiency of this invention is more than 200 times higher than that of the 3D finite element method.

[0058] Table 1

[0059] Traditional 2D finite element methods for axial motors fail to account for 3D effects, edge effects, and radial saturation differences, resulting in inherent errors in calculations under both no-load and loaded conditions. This invention analyzes the 3D, edge, and saturation effects of axial motors analytically. Based on the traditional 2D finite element method at the average radius of the axial motor, correction coefficients for flux linkage, back EMF, and torque are proposed, reducing inherent errors. Using 3D finite element results as a benchmark, under no-load conditions, the corrected fundamental flux linkage error decreases from 2.91% to 0.39%, and the back EMF error decreases from 2.93% to 0.31%. Under rated operating conditions, the torque error decreases from 2.77% to 0.64%.

[0060] This embodiment also provides a hybrid analytical device for axial motors based on two-dimensional finite element method. This device is used to implement the above embodiments and preferred embodiments, and details already described will not be repeated. As used below, the term "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0061] This embodiment provides a hybrid analytical device for axial motors based on two-dimensional finite element method. The device includes: The model building module is used to build an equivalent model at the average radius of the axial motor. The acquisition module is used to obtain initial electromagnetic performance parameters based on the equivalent model at the average radius of the axial motor. The calculation module is used to calculate the saturation effect and 3D effect of the motor using analytical methods, and to calculate the correction coefficient. The correction module is used to correct the initial electromagnetic performance parameters using correction coefficients.

[0062] The axial motor hybrid analysis device based on two-dimensional finite element method provided in this embodiment of the invention can execute the axial motor hybrid analysis method based on two-dimensional finite element method provided in any embodiment of the invention, and has the corresponding functional modules and beneficial effects of the method. Further functional descriptions of the above modules and units are the same as in the corresponding embodiments described above, and will not be repeated here.

[0063] Figure 8 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention.

[0064] The following is a detailed reference. Figure 8 The diagram illustrates a structural schematic suitable for implementing an electronic device according to embodiments of the present invention. The electronic device may include a processor (e.g., a central processing unit, graphics processor, etc.) 001, which can perform various appropriate actions and processes according to a program stored in read-only memory (ROM) 002 or a program loaded from memory 008 into random access memory (RAM) 003. The RAM 003 also stores various programs and data required for the operation of the electronic device. The processor 001, ROM 002, and RAM 003 are interconnected via bus 004. An input / output (I / O) interface 005 is also connected to bus 004.

[0065] Typically, the following devices can be connected to I / O interface 005: input devices 006 including, for example, touchscreens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices 007 including, for example, liquid crystal displays (LCDs), speakers, vibrators, etc.; memory devices 008 including, for example, magnetic tapes, hard disks, etc.; and communication devices 009. Communication device 009 allows electronic devices to exchange data via wireless or wired communication with other devices. Although Figure 8 Electronic devices with various devices are shown, but it should be understood that it is not required to implement or have all of the devices shown, and more or fewer devices may be implemented or have instead.

[0066] In particular, according to embodiments of the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of the present invention include a computer program product comprising a computer program carried on a non-transitory computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be downloaded and installed from a network via communication device 009, or installed from memory 008, or installed from ROM 002. When the computer program is executed by processor 001, it performs the functions defined in the hybrid analytical method for axial motors based on two-dimensional finite element analysis according to embodiments of the present invention.

[0067] Figure 8 The electronic device shown is merely an example and should not be construed as limiting the functionality and scope of use of the embodiments of the present invention.

[0068] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code. When the software or computer code is accessed and executed by the computer, processor, or hardware, the hybrid analytical method for axial motors based on two-dimensional finite element analysis shown in the above embodiments is implemented.

[0069] A portion of this invention can be applied as a computer program product, such as computer program instructions, which, when executed by a computer, can invoke or provide the methods and / or technical solutions according to the invention through the operation of the computer. Those skilled in the art will understand that the forms in which computer program instructions exist in a computer-readable medium include, but are not limited to, source files, executable files, installation package files, etc. Correspondingly, the ways in which computer program instructions are executed by a computer include, but are not limited to: the computer directly executing the instructions, or the computer compiling the instructions and then executing the corresponding compiled program, or the computer reading and executing the instructions, or the computer reading and installing the instructions and then executing the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible to a computer.

[0070] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A hybrid analytical method for axial motors based on two-dimensional finite element method, characterized in that, The method includes: Establish an equivalent model at the average radius of the axial motor; Based on the equivalent model at the average radius of the axial motor, the initial electromagnetic performance parameters are obtained. The saturation effect and 3D effect of the motor are calculated using analytical methods, and the correction coefficient is obtained. The initial electromagnetic performance parameters are corrected using the correction coefficient.

2. The hybrid analytical method for axial motors based on two-dimensional finite element method according to claim 1, characterized in that, The initial electromagnetic performance parameters include: magnetic flux linkage, back electromotive force, and electromagnetic torque.

3. The hybrid analytical method for axial motors based on two-dimensional finite element method according to claim 1, characterized in that, The process of establishing an equivalent model at the average radius of the axial motor includes: Take an annular cross-section at the average radius of the motor; Unfold the annular cross-section to obtain a two-dimensional model of the permanent magnet linear motor; The mover velocity of the two-dimensional model of the permanent magnet linear motor is the linear velocity at the average radius of the three-dimensional model; The electric thrust calculated from the two-dimensional model is converted into electromagnetic torque.

4. The hybrid analytical method for axial motors based on two-dimensional finite element method according to claim 2, characterized in that, The process of calculating the magnetic flux correction factor includes: The fundamental magnetic flux of the air gap is obtained by integrating the fundamental amplitude of the air gap magnetic flux at different radii of the axial motor. Calculate the air gap fundamental magnetic flux of the equivalent model at the average radius; The ratio of the air gap fundamental flux to the air gap fundamental flux of the axial motor is used as the flux correction coefficient.

5. The hybrid analytical method for axial motors based on two-dimensional finite element method according to claim 4, characterized in that, The process of obtaining the fundamental amplitude of the air gap magnetic flux density at different radii of an axial motor includes: Calculate the pole width at different radii based on the width of the permanent magnet at the inner and outer diameters and the length of the inner and outer radii; Based on the magnetic pole widths at different radii, calculate the span angle of the permanent magnet at different radii and the pole arc coefficient that varies with the radius; The no-load air gap magnetic flux density distribution of the motor is approximated as a square wave with a preset amplitude. The pole arc coefficient, which varies with the radius, is decomposed by Fourier series and combined with the edge effect correction function to obtain the fundamental amplitude of the air gap magnetic flux density at different radii of the axial motor.

6. The hybrid analytical method for axial motors based on two-dimensional finite element method according to claim 5, characterized in that, For surface-mounted permanent magnet axial motors, the process of calculating the electromagnetic torque correction coefficient includes: Based on the integral relationship between permanent magnet flux linkage and permanent magnet flux density, and combined with the fundamental amplitude of permanent magnet flux density and the amplitude of permanent magnet flux density under core saturation, the electromagnetic torque correction coefficient is derived through the electromagnetic torque calculation formula.

7. The hybrid analytical method for axial motors based on two-dimensional finite element method according to claim 6, characterized in that, The process of obtaining the amplitude of the permanent magnet flux density under core saturation includes: Using two-dimensional finite element simulation data, the amplitude of the fundamental air gap magnetic flux density at the average radius under the current load condition was calculated; By performing magnetic flux density integration, the magnetic flux density of the permanent magnet and the magnetic flux density of the stator core at the current radius position are calculated respectively. Based on the magnetic flux density of the permanent magnet and the magnetic flux density of the stator core at the current radius position, and combined with the magnetic flux density-magnetic field strength relationship curve of the core material, the permeability of the core corresponding to the current core magnetic flux density is obtained by interpolation calculation. Based on the motor geometry and core permeability at the current radius, calculate the magnetic reluctance of each part of the motor's magnetic circuit at that radial position. The calculated total magnetomotive force is compared with the preset average magnetomotive force by the difference: If the absolute value of the difference between the total magnetomotive force and the preset average magnetomotive force is less than the set error threshold, it is determined that the air gap magnetic flux density iteration at the current radius has converged, the iteration is stopped, and the final air gap magnetic flux density fundamental amplitude value and the corresponding permanent magnet magnetic flux density amplitude value at the current radius are recorded. Calculate the magnetic reluctance of each part, and calculate the permanent magnet flux density amplitude at the current radius according to the magnetic circuit method. This permanent magnet flux density amplitude is the permanent magnet flux density amplitude under the condition of core saturation.

8. A hybrid analytical device for axial motors based on two-dimensional finite element method, characterized in that, The device includes: The model building module is used to build an equivalent model at the average radius of the axial motor. The acquisition module is used to acquire initial electromagnetic performance parameters based on the equivalent model at the average radius of the axial motor; The calculation module is used to calculate the saturation effect and 3D effect of the motor using analytical methods, and to calculate the correction coefficient. A correction module is used to correct the initial electromagnetic performance parameters using the correction coefficient.

9. An electronic device, characterized in that, include: The system includes a memory and a processor, which are interconnected. The memory stores computer instructions, and the processor executes the computer instructions to perform the hybrid analytical method for axial motors based on two-dimensional finite element method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to execute the hybrid analytical method for axial motors based on two-dimensional finite element method as described in any one of claims 1 to 7.

11. A computer program product, characterized in that, Includes computer instructions for causing a computer to execute the hybrid analytical method for axial motors based on two-dimensional finite element method as described in any one of claims 1 to 7.

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