Study On Electromagnetic Noise Of Permanent Magnet Synchronous Motor Based On Magnetostrictive Effect

As an important energy conversion device,electrical machinery is widely used in industry and agriculture and people’s daily life.In the permanent magnet motor,the permanent magnet excitation method is adopted,which simplifies the structure of the motor,improves the reliability,saves copper,eliminates the rotor copper consumption,and improves the efficiency of the motor.Because of its small size,high operation efficiency,and in many cases of permanent magnet motor can realize brushless,so there are a large number of applications in various electrical appliances,medical equipment,aerospace and defense fields.In the actual operation of the motor,there will be a certain degree of noise,and the sources of these noises can be divided into three categories: mechanical noise,air noise and electromagnetic noise.In the past,the research on the electromagnetic noise of motor mainly focused on the influence of electromagnetic force on the vibration of motor stator.With the further study,the magnetostrictive effect has a certain impact on the motor noise.Therefore,in order to study the permanent magnet synchronous motor considering no-load electromagnetic noise and without considering the magnetostrictive effect of the permanent magnet synchronous motor,geometric modeling,and then use the analysis of permanent magnet synchronous motor magnetic field and mechanical field finite element method,electromagnetic simulation analysis of the mechanical coupling the sound field analysis is applied to the motor such as electromagnetic force and magnetostrictive force results,finally through the analysis of the sound field around the size of the motor to study the magnetostrictive effect of permanent magnet synchronous motor no-load electromagnetic noise.As one of the problems inherent in permanent magnet motors,cogging torque can also cause a certain degree of vibration of the permanent magnet motor to affect the propagation of noise in its surrounding space.Generally,there are many ways to weaken the cogging torque in the permanent magnet motor.One of the common ones is to weaken the cogging torque of the motor by means of the motor stator teeth.In this paper,based on the permanent magnet motor cogging torque suppression method in a stator tooth to open the auxiliary slot method,simulation analysis of the motor in different types of pole slot,stator teeth different auxiliary slot number of cogging torque Size and change of the stator teeth,and the influence of the magnetostrictive effect on the no-load electromagnetic noise of the stator teeth is studied.By studying the deformation,stress,vibration and noise of stator teeth under the effect of magnetostriction force and electromagnetic force,we can find out the law and influence of magnetostrictive effect and electromagnetic force on the vibration noise of permanent magnet synchronous motor,And to eliminate the vibration noise generated by it to provide some reference.