The Test And Vibration Noise Analysis Of The Permanent Magnet Synchronous Motor In Ship Electronic Propulsion

There is so much noise in ship.The origin of the noise is in electric propulsion,including vibration noise,harmonic noise,electromagnet noise in radiation and reception.This noise will have bad effect on the system and the worker may not control the ship effectively.In this paper,we analyze the the vibration and noise,including theory and simulation.Firstly,we analyze the origin of the noise in PMSM,concluding that radial magnetic force being the main reason.In conclution,we establish formulas of radial magnetic flux density,tangential magnetic flux density,radial magnetic force and tangential magnetic force.We make the simulation of radial flux density,tangential flux density waveform,and FFT analysis in Ansoft software;simulation of radial electromagnetic force density,tangential electromagnetic force density,corresponding frequency analysis is also carried out,also calculates the torque characteristics of the motor,and provides a theoretical basis for the simulation and analysis of frequency characteristics of noise.Secondly,the factors influencing the composition of the magnetic field inside the motor are analyzed.The magnetic field inside the motor is simulated and the internal harmonic of the motor is analyzed.The 8-pole 24-slot,8-pole 36-slot,as the object of study,when the different tooth groove with the motor design.Simulation shows that the harmonic of the motor is mainly a multiple of the fourth harmonic.In the process of motor design,the harmonic rules of the motor can be obtained by the above design rules.It is an important reference for motor selection in the project,taking into account the harmonics generated by the tooth groove of the motor and the natural frequency of the motor.According to the mechanical characteristics and the characteristics of the electromagnetic field,the electromechanical coupling equation of the motor vibration analysis is established,and the vibration mode of the motor in the first 6 steps is given.The three-dimensional model of the motor is drawn by using Pro / E three-dimensional software.The simulation of the vibration mode of the motor and the natural frequency of each order are carried out by ANSYS simulation.The simulation of the first 6 orders of the motor is given.An important reference for motor design.In the motor design,to choose the control mode,to avoid the motor harmonic frequency and the motor itself is close to the natural frequency of resonance,affecting the normal work of the motor.Finally,a permanent magnet synchronous motor vibration and noise test software based on LabView is designed to realize the test test of the motor.Using the hammering method to carry out the modal test,get the natural frequency of the motor,compared with the simulation results,prove the reliability of the simulation,the frequency and noise of the motor are measured,and the frequency range of the main peak of the motor noise and vibration is given.The frequency range of the large noise of the motor is analyzed,and the spectral curve measured by the virtual platform is analyzed.