Optimization Of Electric Vehicle Drive System Torsional Vibration By Reducing Torque Fluctuations Of The Motor

With the development of electric vehicles,the torsional vibration problem of electric vehicles with a changed power source has been a hot research.For electric vehicles,the power source changes from the torque ripple of the engine to the drive motor.During the operation of the motor,the torque ripple caused by the nonlinear characteristics of the inverter and the structure of the motor is directly transmitted to the drive train components and causing drive train torsional vibration.So I reduce the harmonics of the inverter circuit for supp-ressing motor torque fluctuations to achieve the purpose of optimizing torsional vibration of the electric vehicle drive train.Firstly,The article analyzes the principle of PMSM and the influence of the nonlinearity of the inverter on the torque based on the mathematical model of PMSM.Then I constructed a motor control system model through matlabsimulink platform.After the simulation,it is found that there are a large number of highorder harmonics such as 5th,7th in working currents of the motor and torque have 6th?12th order fluctuations.Secondly,I using Amesim software construct a physical model including reducer,a differential,shafts,and driving wheels which can help me obtain the natural frequnecies and mode shapes.It is found that when electric vehicles are traveling at speeds of 3.2km/h and 12km/h,more severe resonance phenomena are likely to occur.Highorder harmonics of motor torque are suppressed at this vehicle speed.It is necessary to suppress the highorder harmonics of the motor torque at this vehicle speed.For this I reduce the highorder waves in the torque ripple of the motor by suppressing the harmonic current.And Finding it works by matlab / simulink simulation plat-form.Finally,the motor torque transfer to the physical model of the drive train through Matlab / simulink and Amesim joint simulation technology.The simula-tion results under different operating conditions show that during acceleration harmonics have a small effect on the torsional vibration of the drive train and under uniform speed condition the torsional amplitude of each component of the drive train decreases significantly after harmonic suppression which proved that the motor torque harmonic suppression have an optimized effect on the drive train torsional vibration.