Research On Acoustic Simulation And Sound Quality Optimization Of Vehicle Drive Motor

Permanent magnet synchronous motors are widely used in hybrid and pure electric vehicles due to their lower cogging torque,better field weakening capability and fault tolerance.Motor noise becomes an important noise source for hybrid and pure electric vehicles,which seriously affects the ride comfort of the vehicle.For the electromagnetic noise analysis of the motor,the main focus is on the radial electromagnetic force and the electromagnetic force component is ignored,which causes the analysis accuracy to be inaccurate.This article takes 8-pole,24-slot permanent magnet synchronous motors as research objects,and conducts acoustic performance research including electromagnetic noise simulation calculations,noise tests,and electromagnetic noise optimization,which can be used to guide the design and development of NVH performance of permanent magnet synchronous motors.Perform modal analysis on the permanent magnet synchronous motor,establish a finite element model of the motor stator and perform modal simulation analysis to obtain the modal shape and its corresponding natural frequency.At the same time,perform a free modal test on the permanent magnet synchronous motor by hammering The modal simulation and experimental results of PMSM are compared to verify the accuracy of the modal analysis of the motor and the finite element model of the stator.The method of simulation and experiment was used to study the electromagnetic noise of permanent magnet synchronous motors.First,the electromagnetic simulation of the permanent magnet synchronous motor is performed to obtain the magnetic field and electromagnetic force distribution of the motor at the rated speed.Then the electromagnetic force is loaded on the motor stator structure model.The modal superposition method is used to simulate the calculation of the motor vibration and the indirect boundary element method is used to predict the Electromagnetic noise.Finally,the motor noise test test proves the accuracy of electromagnetic noise simulation analysis.It is found that radial electromagnetic force is the main source of electromagnetic noise for permanent magnet synchronous motors,but tangential electromagnetic force also has a certain effect on electromagnetic noise.Finally,the effects of different structural parameters on electromagnetic noise were studied based on electromagnetic and acoustic simulations of permanent magnet synchronous motors.By changing the width of the stator slot of the motor and the radius of the magnet 's fillet,the influence of the electromagnetic force on the amplitude and harmonic components of the electromagnetic force is studied,and the corresponding changes in electromagnetic noise are further studied from the perspective of sound pressure level and sound quality.Reducing the stator slot width and magnet fillet radius of a permanent magnet synchronous motor can both reduce the sound pressure level of electromagnetic noise and optimize the sound quality of electromagnetic noise based on objective evaluation.