Hierarchical Sensitivity Optimization Design Of An Interior Permanent Magnet Synchronous Motor Considering Vibration And Noise Suppression

Interior Permanent Magnet Synchronous Motor(IPMSM)is widely used in rail transit,new energy vehicles,industrial robots and other intelligent fields.As the motor gradually develops to the direction of high power density,high efficiency,high stability and wide speed range,the magnetic density load of the motor is enhanced,and the electromagnetic vibration and noise of the motor is increasingly prominent.At the same time,the vibration and noise of the motor will bring negative impact on the comfort and stability of the motor application scene.Based on a interior permanent magnet synchronous motor with rated power of 80 kW,the multiobjective optimization design of the motor was carried out and its vibration and noise characteristics were analyzed.The research content was divided into the following four parts:(1)The magnetic potential multiplier permeability method was used to solve the radial air gap magnetic density expression of the motor,so as to deduce the change law of the radial electromagnetic force with time and space.The modal frequency,structural vibration and sound pressure level transfer theory of the motor were calculated analytically,and the theoretical law of the radial electromagnetic force of the motor on electromagnetic vibration and noise was analyzed.(2)Aiming at the problems of complex IPMSM rotor structure and numerous optimization topological parameters,a hierarchical optimization design method of parameter sensitivity was proposed.Firstly,the sensitivity analysis and stratification of the motor parameters were carried out,and the parameter optimization interval was accurately positioned by the response surface method.The first layer parameters are optimized by improved genetic algorithm,and the second layer parameters are optimized by parameter scanning method,and the final optimization results are verified by finite element method.(3)The finite element simulation model of interior permanent magnet synchronous motor was built in the electromagnetic field to compare the optimization effect of electromagnetic performance such as electromagnetic torque and radial electromagnetic force of the motor;The radial electromagnetic force is decomposed into spatial order and time frequency Fourier transform,and the amplitude changes of each order before and after optimization are compared.(4)In order to better analyze the vibration and noise performance of the motor,the multiphysical field simulation optimization scheme of the motor was proposed.The radial electromagnetic force was used as the medium to coupling the electromagnetic field,mechanical field and sound field,and the vibration and noise characteristics of the stator amplitude and sound pressure level transfer were compared and analyzed before and after the motor optimization.At the same time,the modal shape and frequency of the motor stator and stator assembly are simulated.Finally,the equivalent stress and total deformation of the rotor under the rated speed were solved in the mechanical field.