| Permanent magnet synchronous motor(PMSM)is widely used in precision machine tools,precision instruments,deep-sea equipment,aerospace equipment,defense industry,industrial robots and other fields.The research on its magnetic field analysis and structure optimization is the basis and premise of high-performance motor design.This paper focuses on the magnetic field analysis and structure optimization of surface mounted permanent magnet synchronous motor(SMPMSM)According to the motor structure and magnetic circuit characteristics of SMPMSM,the magnetic field solution region of the motor is divided into rotor region,air gap region and stator region by using sub domain model method.The magnetic field of the motor is solved by establishing magnetic field constraint equations and boundary conditions between the regions.On this basis,the electromagnetic performance of the motor is calculated,which is the basis of SMPMSM The foundation of general magnetic field analytical modeling and electromagnetic analysis of complex magnetic circuit structure is established.Segmented skew pole is an effective and practical magnetic pole structure to reduce cogging torque and torque fluctuation.In this paper,a 3-D magnetic field analytical modeling method is proposed for segmented skew pole surface mounted permanent magnet motor.The electromagnetic properties of the motor,such as back EMF and torque,are calculated and compared with the finite element calculation results,which verifies the application of the analytical model in different segmented skew pole The accuracy of the test results under different conditions.At the same time,the analytical model can be used to quickly traverse the electromagnetic calculation results under different segmented oblique pole parameters,and analyze the influence of the number of oblique pole segments,oblique pole angle,circumferential segmented number and segmented gap on the electromagnetic performance of the motor,which greatly improves the efficiency of calculation and analysis,and provides valuable reference for the optimal design of segmented oblique pole SMPMSM.The unbalanced magnetic pull(UMP)will affect the smooth operation of the motor and aggravate the vibration and noise of the motor.In view of the UMP caused by the different number of slots in each pole and phase and the uneven distribution of air gap magnetic field in the circumferential direction of fractional slot motor,an improved structure of magnetic pole is proposed to change the shape and magnetization mode.On this basis,by selecting the appropriate structural parameters as the optimization variables,according to the orthogonal table for many groups of experiments,using mathematical statistics method to analyze the influence of each parameter on the motor UMP and torque fluctuation,so as to determine the final scheme,and realize the improvement of motor performance. |
