Research On The Analysis And Suppression Measures Of The Electromagnetic Noise Of A Certain Type Of High-speed Permanent Magnet Synchronous Motor

The permanent magnet synchronous motor has good mechanical properties,simple structure and high efficiency.It has been widely used in space aviation,new energy automobile,household appliances and power system transmission control.As a noise source,the high noise level of permanent magnet synchronous motor will directly improve the noise level of the surrounding environment.And this will seriously affect people's life and work.Considering the motor electromagnetic noise is generated by the motor internal magnetic field effect,directly affect the strength of the motor noise,so the electromagnetic noise problem of permanent magnet synchronous motor has become a need to solve the problem.With the help of the national precision micro-motor engineering technology research center,this project is the research object of the LQTB-1 high speed permanent magnet synchronous motor.The influence factors of its electromagnetic noise are analyzed and the corresponding measures to suppress the electromagnetic noise are put forward.The specific research contents are as follows:(1)The magnetic flux density and electromagnetic excitation force of lqtb-1 permanent magnet synchronous motor are analyzed theoretically.The harmonic frequency of the electromagnetic excitation force of lqtb-1 motor is calculated.(2)The influence of magnetic circuit structure on electromagnetic excitation force is analyzed.And find the following conclusions.Reducing the width of the stator slot can reduce the radial force to suppress the generation of electromagnetic noise.The influence of the extreme pole coefficient on the radial electromagnetic excitation force is "V",and the influence on the cogging torque of the motor is also fluctuated.For LQTB-1 permanent magnet synchronous motor,the pole coefficient selection 0.85,which can suppress the electromagnetic noise to the maximum extent.The slant groove design can reduce the torque of the motor,which can reduce the torque ripple and suppress the electromagnetic noise.(3)Based on the proposed electromagnetic noise suppression measures,the electromagnetic noise of the motor before and after the optimization of the motor magnetic circuit structure is solved by means of simulation.The test data are measured by the motor noise test,and the effectiveness of the control measures is verified by comparison.(4)Analyze the vibration characteristics of motor stator system and rotor structure and solve the natural frequency of each part of the motor.