Research And Analysis Of Electromagnetic Vibration And Noise Of Permanent Magnet Synchronous Motor

The position of permanent magnet synchronous motor in the industrial field is very important,and vibration and noise are the key factors to evaluate the quality of the motor,and electromagnetic vibration and noise are the main ones.This article analyzes and improves electromagnetic vibration and noise.The main contents are as follows:First,starting from the principle of electromagnetic vibration and noise of permanent magnet synchronous motors,based on the magnetic potential permeance method,a more accurate analytical model of radial electromagnetic force waves is constructed,and the radial air gap magnetic density is deeply studied,The precise expression of radial force is derived in detail.By changing the number of pole pairs and the number of stator slots,the influence of integer slots and fractional slots on the order of radial force waves is analyzed.Secondly,a finite element simulation model of a permanent magnet synchronous motor is constructed,and the different proportions of the magnetic close component and the radial component of the air gap of the motor are studied,and the main force wave order of the two-dimensional simulation diagram of the radial electromagnetic force is obtained.Then the three-dimensional simulation image of the radial air gap magnetic density and the radial electromagnetic force is obtained through joint simulation,and further Fourier decomposition is performed to obtain the corresponding radial force wave amplitude,order and frequency in space.This verifies the correctness of the analytical model.Then,the analytical analysis method and finite element method are used to study the stator system.The modal characteristics of permanent magnet synchronous motor stator core are analyzed from multiple levels and dimensions,and the vibration modes and frequencies under different modes are obtained,and the relationship between material parameters of stator core and modal vibration mode and frequency is found out.In addition,the winding structure is simplified for many times,and then the finite element modeling method of stator winding is optimized on this basis,and the specific changes of modal characteristics caused by the change of winding slot full rate are clarified.Finally,the electromagnetic vibration and noise of the motor are studied and calculated by using the new analytical model of electromagnetic vibration and noise.Based on the electromagnetic analysis and modal analysis,the coupling simulation is carried out,and the displacement,velocity and acceleration images of the motor vibration in different directions are obtained.On the basis of the vibration results,the spherical and cylindrical radiators are selected,and the noise spectrum is obtained.Using the above simulation images,the influence of amplitude,spatial order and frequency of radial electromagnetic force on electromagnetic vibration is studied.It is found that when the radial electromagnetic force of low spatial order and the frequency of radial electromagnetic force are close to and equal to the frequency of stator system,the electromagnetic vibration noise will be greater.In order to reduce the electromagnetic vibration and noise,the above force wave should be weakened and eliminated.