Vibration And Noise Analysis Of Permanent Magnet Synchronous Motor Of Blade Electric Vehicles

With the deteriorating global ecological environment and energy shortage,the demand for electric vehicles is on the rise.Automobile companies all over the world are further improving the related technologies of electric vehicles.At present,China is vigorously promoting the development of Blade Electric Vehicles(BEV).The biggest difference between Blade Electric Vehicles and an internal combustion engine vehicle is that the driving structure is changed from an internal combustion e ngine to an electric motor.As a result,many changes have taken place in the characteristics of electric vehicles noise,The most significant is that the high frequency noise of the drive motor is more prominent than the low frequency noise.In this paper,a common permanent-magnet synchronous motor of Blade Electric Vehicles is taken as the research object,study the characteristics of the vibration noise of the drive motor,and the prediction of the high frequency noise of the drive motor of the Blade Electric Vehicles is made.First of all,the analytical solution and the ANSYS maxwell module are used respectively to analyze and simulate the air gap magnetic field of the permanent magnet synchronous motor under both sinusoidal current and frequency converter power supply,and based on the inverter power supply introduced a large number of switching frequency and harmonics near the multiplier resulting in high frequency noise motor.Using MATLAB to extract and calculate the peak frequency of the air gap magnetic field under different switching frequencies,the relationship between the radial electromagnetic force frequency and the switching frequency of the air-gap caused by high frequency noise of the motor was obtained,provide a theoretical basis for the prediction of high frequency peak noise.Secondly,the dynamic characteristics of the whole motor and its components are studied,and then the vibration noise of the motor is analyzed.Through SolidWorks establish 3D model of the motor and its stator system,based on ANSYS workbench software to simplify the motor and stator r structural modal analysis,the simulation results in the motor under the actual installation conditions and the stator system of low-order natural frequency and vibration mode diagram.Finally,the permanent magnet synchronous motor was tested for the vibration characteristics and the vibration acceleration and noise sound pressure level of the motor were measured.Use LMS.Test software for data processing,and according to the analysis of power-off method,it is found that the mechanical noise of the motor is mainly in the low frequency range,and the high-frequency vibration noise is caused by the power supply of the frequency converter.Then by summarizing the rules presented by the exper imental data,The accuracy of the relationship between the radial electromagnetic force and the switching frequency derived from the simulation is verified,which provides reference value for the design of the motor and its noise prediction.