Research On Vibration And Noise Of Permanent Magnet Linear Motor Considering Magnetostriction

As the core device of linear motion equipment,permanent magnet linear synchronous motors are widely used in many fields,such as magnetic levitation trains in the transportation industry,and the ejection systems of electromagnetic aircraft in the national military industry.Linear motors can be seen everywhere in people’s production and life,and the vibration and noise generated at the same time have attracted people’s attention.The electromagnetic vibration of the linear motor is determined by the electromagnetic force and the magnetostrictive effect at the same time.When the magnetostrictive effect is considered,the prediction of vibration and noise is more accurate.This paper mainly studies the vibration and noise of the primary structure of the linear motor based on the electromagnetic force considering the magnetostrictive effect.Firstly,a 10-pole 12-slot permanent magnet linear synchronous motor was designed.The material of the primary core is non-oriented silicon steel sheet.In addition,the natural frequencies and modes of the primary structure are calculated,and the frequency acceleration response of the primary structure when only electromagnetic force is considered and the frequency acceleration response of the primary structure after considering the magnetostrictive effect based on electromagnetic force are analyzed.Secondly,the COMSOL Multiphysics software is used to analyze the vibration and noise of the permanent magnet linear synchronous motor.The realization method adopts the electromagnetic-structure-acoustic field synchronous coupling method.The effective magnetic field of the material includes the contribution of the magnetic field applied by the electromagnetic module and the mechanical stress of the structure field to the effective magnetic field(called the Villari effect).In the structural field,the stress of the primary structure of the linear motor is analyzed,including three situations: the stress when the electromagnetic force is considered,the stress when the magnetostrictive effect is considered,and the stress when the electromagnetic force and the magnetostrictive force are considered at the same time.Then,the vibration acceleration and vibration velocity characteristics of the linear motor’s primary structure are analyzed,including two cases: the case where only electromagnetic force is considered,and the case where electromagnetic force and magnetostrictive force are considered at the same time.Finally,the noise generated by the permanent magnet linear synchronous motor during the movement is analyzed,and two situations are compared and analyzed: only the electromagnetic force is considered,and the electromagnetic force and the magnetostrictive force are considered at the same time.The sound field distribution in the two cases is analyzed,and the reference point is selected in the area where the sound waves are concentrated to analyze the decibel characteristics in the two cases.