Optimal design of submersible permanent magnet synchronous motor with double-assisted permanent magnet Halbach array based on SVM

Key words:  air gap magnetic density  fundamental amplitude  oil submersible permanent magnet synchronous motor  support vector machine

Abstract:

The harmonics and fundamental amplitude of air gap flux density will directly affect the performance of the oil-submerged permanent magnet synchronous motor. To analyze and optimize the air gap magnetic density of this motor, a surface oil-submerged permanent magnet synchronous motor with double auxiliary permanent magnet Halbach array structures was designed and optimized. The permanent magnets of the motor was magnetized by the Halbach method. The magnetizing direction of the main magnet is the radial magnetizing, and the magnetizing directions of the double auxiliary magnets are the parallel magnetizing in different directions. The thickness and width for the double auxiliary magnets and the main magnets are not equal. In order to reduce the cost of calculation and improve the computational efficiency, the nonlinear regression model of support vector machine was used to fit the optimization objectives, and multi-objective optimization was carried out. The finite element method was used to compare the oil-submerged permanent magnet synchronous motor before and after optimization. The results show that the Halbach structure of double auxiliary permanent magnets can effectively reduce the harmonics of air gap magnetic flux density, and can also improve its fundamental amplitude.