Simulation Analysis And Test Of Vibration Characteristics Of Permanent Magnet Synchronous Motor

In recent years,pure electric vehicles have developed rapidly.Unlike fuel vehicles,the main power source for pure electric vehicles is electric motors.In this thesis,the permanent magnet synchronous motor is research object.Optimizing the co-simulation method,studied the vibration characteristics of the motor under the nonlinear influence between the machineelectric-magnetic-controlled,then verified this by experiments.The main research contents and conclusions of this thesis are as follows:(1)Studing the joint simulation method of permanent magnet synchronous motor,using a joint simulation method which considered the interaction of machine-electro-magneticcontrol.The optimized method is realized by three softwares: Maxwell,Simplorer,Simulink and LMS Virtual.Lab.This method considers factors such as stator slot and permanent magnet field in the magnetic field,the modulation mode and dead-time in the control,and the axis misaligNment in the machine.Coupling factors such as neutralization imbalance.Compared with the existing methods,the proposed method is closer to reality.(2)When the motor in the ideal working condition,analyze the current,torque,electromagnetic force and bearing force time-frequency characteristics of the two methods.In time domain the four parameters' s waveform variation trend and the harmonic amplitude in the frequency domain are same.It can prove the correctness of the method which is used in this paper.(3)Contrasting and analying the electromagnetic force spectrum characteristics of the machine-electric-magnetic-controlled method and the existing method when the rotor shaft is misalignment.The electromagnetic force obtained by the optimized joint simulation method has a modulation phenomenon about the frequency conversion,which is impossible for the existing method.The motor's angle,speed and load have an impact on the spectral characteristics of electromagnetic force,summarizing this influence by three conditions: variable angle,variable speed and variable load.Also proved the universality of the simulation method.(4)The dynamic eccentricity of the motor take a impact on the time domain,angular domain and frequency domain of the air-gap magnetic-density and electromagnetic force.The dynamic eccentricity make the electromagnetic force waveform distorted,and produces a frequency modulation on the basis of the original frequency in the frequency domain.Analysising the two kinds of eccentricity,found it does not change the frequency component of the electromagnetic force,but the harmonic amplitude of the electromagnetic force increases with the eccentricity.(5)Setting up test bench of the motor vibration and writing the motor drive program,then collect the casing acceleration signal under different working conditions.The acceleration's frequency distribution is consistent with the electromagnetic force obtained by the simulation,which verifies the correctness of the electro-magnetic-magnetic-controlled method,and showing the method can reflected more vibration characteristics of the motor when motor under fault conditions.