Permanent magnet synchronous motor multi-objective optimization method fusing equivalent magnetic network method and Taguchi method

Abstract

The invention discloses a permanent magnet synchronous motor multi-objective optimization method fusing an equivalent magnetic network method and a Taguchi method, and relates to the technical field of permanent magnet synchronous motor optimization. The method comprises the following steps: step 1, establishing an equivalent magnetic network model of the permanent magnet synchronous motor; 2, determining an optimization target of optimization design under the fusion of the equivalent magnetic network method and the Taguchi method; 3, determining an optimization factor according to the influence factors of the optimization target; step 4, determining an optimization level according to the selected optimization factor and arranging an orthogonal test; step 5, calculating each scheme by using an equivalent magnetic network method according to an orthogonal test to obtain calculation results of different schemes; 6, analyzing data after calculation results of different schemes are obtained; and 7, determining an optimal control factor combination and an optimal control solution according to data analysis results of different schemes. According to the method, the requirements of multi-target simultaneous optimization and rapid calculation can be met, and the optimization design level and the calculation efficiency of the permanent magnet synchronous motor are effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of permanent magnet synchronous motor optimization, and in particular to a permanent magnet synchronous motor multi-objective optimization method integrating an equivalent magnetic network method and a Taguchi method. Background Art

[0002] As people's demand for the power performance of new energy vehicles grows, improving the power density of drive motors in limited space is a key issue that needs to be solved in the current new energy field. This problem is generally solved from two aspects: one is to improve the torque density of permanent magnet synchronous motors, and the other is to reduce the flat wire winding loss of permanent magnet synchronous motors. However, increasing torque density is often accompanied by an increase in torque pulsation, which is inseparable from the vibration and noise of the motor. Therefore, improving torque density and reducing torque pulsation are one of the design goals of permanent magnet synchronous motors.

[0003] In order to solve the problem of improving the power density of permanent magnet synchronous motors, the current optimization design of permanent magnet synchronous motors mainly uses a single-objective finite element method for repeated calculations or a method combining the finite element method with a multi-objective optimization algorithm for calculations, which cannot meet the requirements of simultaneous optimization of multiple objectives and fast calculations. Therefore, we propose a multi-objective optimization method for permanent magnet synchronous motors that combines the equivalent magnetic network method with the Taguchi method to solve the above problems.

[0004] The above information disclosed in this background technology is only used to increase the understanding of the background technology of the present invention and therefore, it may include information that does not constitute the prior art known to ordinary technicians in this field. Summary of the invention

[0005] The purpose of the present invention is to provide a permanent magnet synchronous motor multi-objective optimization method that integrates an equivalent magnetic network method and a Taguchi method, so as to solve the problem that the existing optimization design cannot satisfy the simultaneous optimization and rapid calculation of multiple objectives.

[0006] To achieve the above object, the present invention provides the following technical solution: a multi-objective optimization method for a permanent magnet synchronous motor integrating an equivalent magnetic network method and a Taguchi method, comprising the following steps:

[0007] Step 1. Establish an equivalent magnetic network model of a permanent magnet synchronous motor;

[0008] Step 2. Determine the optimization target of the optimization design under the fusion of the equivalent magnetic network method and the Taguchi method;

[0009] Step 3. Determine the optimization factor according to the influencing factors of the optimization target;

[0010] Step 4. Determine the optimization level according to the selected optimization factors and arrange orthogonal experiments;

[0011] Step 5. Calculate each scheme using the equivalent magnetic network method according to the orthogonal test to obtain the calculation results of different schemes;

[0012] Step 6. Analyze the data after obtaining the calculation results of different schemes;

[0013] Step 7. Determine the best control factor combination and the best control solution based on the data analysis results of different schemes.

[0014] Preferably, the specific steps of step 1 are:

[0015] Firstly, the division of the equivalent magnetic network model is determined according to the stator, rotor and air gap magnetic flux paths;

[0016] Then determine the magnetomotive force according to the excitation method and stator winding structure;

[0017] Determine the permanent magnet permeability, core permeability and air gap permeability according to each magnetic network unit structure;

[0018] Finally, Kirchhoff's magnetic circuit law is used to obtain the magnetic flux and flux density of different parts of the permanent magnet synchronous motor;

[0019] The torque density and torque ripple of the permanent magnet synchronous motor are calculated based on the magnetic flux and flux density obtained by the equivalent magnetic network method.

[0020] Preferably, the optimization objectives determined in step 2 are torque density and torque ripple.

[0021] Preferably, step 3 determines the optimization factor according to the influencing factors of torque density and torque pulsation, and the optimization factor selects the stator split ratio, stator slot size, magnetic barrier position, magnetic barrier shape, magnetic barrier thickness, number of magnetic barrier layers and air gap size.

[0022] Preferably, in step 5, the magnetic flux and magnetic flux density of each branch are obtained using an equivalent magnetic network model and equations, and then the torque density and torque pulsation are calculated to obtain the torque density and torque pulsation results of different schemes.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] The optimization method of the present invention is simple and easy, can meet the requirements of simultaneous optimization and rapid calculation of multiple objectives, effectively improves the optimization design level and calculation efficiency of permanent magnet synchronous motors, can take into account both torque density and torque pulsation when considering optimization objectives, and can reduce torque pulsation as much as possible while increasing torque density, avoid vibration and noise, and has great application prospects.

[0025] The above summary is for illustrative purposes only and is not intended to be limiting in any way. In addition to the illustrative aspects, embodiments and features described above, further aspects, embodiments and features of the present invention will be readily apparent by reference to the accompanying drawings and the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a flow chart of the multi-objective optimization method of a permanent magnet synchronous motor integrating the equivalent magnetic network method and the Taguchi method of the present invention;

[0027] Figure 2 Calculation flow chart for the equivalent magnetic network method. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] According to one embodiment of the present invention, the torque density and torque ripple of a permanent magnet synchronous motor are taken as an example for optimization. Figure 1 - Figure 2 A multi-objective optimization method for a permanent magnet synchronous motor integrating an equivalent magnetic network method and a Taguchi method comprises the following steps:

[0030] Step 1. Establish an equivalent magnetic network model of a permanent magnet synchronous motor;

[0031] Firstly, the division of the equivalent magnetic network model is determined according to the stator, rotor and air gap magnetic flux paths;

[0032] Then determine the magnetomotive force according to the excitation method and stator winding structure;

[0033] Determine the permanent magnet permeability, core permeability and air gap permeability according to each magnetic network unit structure;

[0034] Finally, Kirchhoff's magnetic circuit law is used to obtain the magnetic flux and flux density of different parts of the permanent magnet synchronous motor;

[0035] Calculate the torque density and torque ripple of the permanent magnet synchronous motor based on the magnetic flux and magnetic flux density obtained by the equivalent magnetic network method;

[0036] Step 2. Determine the optimization target of the optimization design under the fusion of the equivalent magnetic network method and the Taguchi method, and the optimization target is torque density and torque ripple;

[0037] Step 3. Determine the optimization factor according to the influencing factors of torque density and torque pulsation, and select parameters such as stator split ratio, stator slot size, magnetic barrier position, magnetic barrier shape, magnetic barrier thickness, number of magnetic barrier layers and air gap size as the optimization factor;

[0038] Step 4. Determine the optimization level according to the selected optimization factors and arrange orthogonal experiments;

[0039] Step 5. Calculate each scheme using the equivalent magnetic network method according to the orthogonal test, use the equivalent magnetic network model and equation to obtain the magnetic flux and magnetic flux density of each branch, and then calculate the torque density and torque pulsation to obtain the torque density and torque pulsation results of different schemes;

[0040] Step 6. Analyze the data after obtaining the calculation results of different schemes;

[0041] Step 7. Determine the best control factor combination and the best control solution based on the data analysis results of different schemes.

[0042] The present invention can meet the requirements of simultaneous multi-objective optimization and fast calculation. The multi-objective optimization method for permanent magnet synchronous motors provided by the present invention, which integrates the equivalent magnetic network method and the Taguchi method, has a very significant effect on improving the torque density of permanent magnet synchronous motors, reducing torque pulsation, and suppressing vibration and noise. It is convenient and practical and has great application prospects.

[0043] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A multi-objective optimization method for a permanent magnet synchronous motor combining an equivalent magnetic network method and a Taguchi method, characterized in that: The steps include: Step 1. Establish an equivalent magnetic network model of a permanent magnet synchronous motor; Step 2. Determine the optimization target of the optimization design under the fusion of the equivalent magnetic network method and the Taguchi method; Step 3. Determine the optimization factor according to the influencing factors of the optimization target; Step 4. Determine the optimization level according to the selected optimization factors and arrange orthogonal experiments; Step 5. Calculate each scheme using the equivalent magnetic network method according to the orthogonal test to obtain the calculation results of different schemes; Step 6. Analyze the data after obtaining the calculation results of different schemes; Step 7. Determine the best control factor combination and the best control solution based on the data analysis results of different schemes.

2. The multi-objective optimization method for a permanent magnet synchronous motor integrating an equivalent magnetic network method and a Taguchi method according to claim 1 is characterized in that: The specific steps of step 1 are: Firstly, the division of the equivalent magnetic network model is determined according to the stator, rotor and air gap magnetic flux paths; Then determine the magnetomotive force according to the excitation method and stator winding structure; Determine the permanent magnet permeability, core permeability and air gap permeability according to each magnetic network unit structure; Finally, Kirchhoff's magnetic circuit law is used to obtain the magnetic flux and flux density of different parts of the permanent magnet synchronous motor; The torque density and torque ripple of the permanent magnet synchronous motor are calculated based on the magnetic flux and flux density obtained by the equivalent magnetic network method.

3. The multi-objective optimization method for a permanent magnet synchronous motor integrating an equivalent magnetic network method and a Taguchi method according to claim 2 is characterized in that: The optimization targets determined in step 2 are torque density and torque ripple.

4. The multi-objective optimization method for a permanent magnet synchronous motor integrating an equivalent magnetic network method and a Taguchi method according to claim 3 is characterized in that: The step 3 determines the optimization factor according to the influencing factors of torque density and torque pulsation, and the optimization factor selects the stator split ratio, stator slot size, magnetic barrier position, magnetic barrier shape, magnetic barrier thickness, number of magnetic barrier layers and air gap size.

5. The multi-objective optimization method for a permanent magnet synchronous motor integrating an equivalent magnetic network method and a Taguchi method according to claim 4 is characterized in that: In step 5, the magnetic flux and magnetic flux density of each branch are obtained using the equivalent magnetic network model and equations, and then the torque density and torque pulsation are calculated to obtain the torque density and torque pulsation results of different schemes.

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