Simulation Research On Three-Phase Written-Pole Permanent Magnet Synchronous Motor

Permanent magnet synchronous motors are widely used in drive systems of all ways of life,including rail transit,aerospace and people's living environment.As long as it involves converting electrical energy into mechanical energy devices,there are a large number of permanent magnet motor drives.However,permanent magnet synchronous motors also have problems such as fixed pole number,high manufacturing cost,risk of loss of magnetism and troublesome troubleshooting.The writtenpole permanent magnet synchronous motor can better solve the fault problem that the pole number of the permanent magnet cannot be changed and the risk of loss of magnetism,and has the advantages of large starting torque,fast speed range,and operation at a very low synchronous speed.There have been some research and applications in foreign countries,but at present,domestic research on written-pole motors is still in a blank stage.Therefore,the in-depth study of the written-pole permanent magnet synchronous motor has important theoretical significance and value for written-pole motors in China.Based on the analysis of the structure and principle of the writtenpole permanent magnet synchronous motor,this paper studies the structure and operation of the three-phase written-pole permanent magnet synchronous motor.The main work is as follows:(1)For the principle of the three-phase written-pole permanent magnet synchronous motor,the pole-changing mode of the stator winding and the way in which the rotor is filled with the magnetic pole are determined.(2)The excitation circuit model of the three-phase written-pole permanent magnet synchronous motor is established,and the magnetization model of the magnet is determined.The magnetization model is based on the variation law of the hysteresis loop of the magnet,and the BP neural network algorithm is used to predict the local hysteresis loop.The model was fitted.The magnitude of the magnetizing current is finally determined.(3)In order to determine the influence of the magnetizing current on the magnetization of the magnet layer of the three-phase written-pole permanent magnet synchronous motor,the two-dimensional dynamic simulation model of the body is established by Ansys Maxwell software,and the magnetizing current characteristics and the motor magnetic field distribution during steady state are established.The simulation analysis shows that the magnetic field characteristics are consistent with the characteristics of permanent magnet synchronous motor at 2 and 4 poles,as well as the optimal saturation magnetization current and reverse demagnetization current characteristics.(4)According to the principle and mathematical model of the three-phase written-pole permanent magnet synchronous motor,the Matlab/Simulink simulation model is built.Finally,the starting characteristics and no-load characteristics,load characteristics and overload conditions of the motor are simulated and synchronized with the permanent magnet.The motor is compared to verify that the three-phase written-pole permanent magnet synchronous motor has a large starting speed,a wide synchronous speed range and a short starting time.