Analysis of Magnetic Field Characteristics of PMSM Under Typical Abnormal Conditions

In this paper, the permanent magnet synchronous motor is taken as an example to analyze the difference of detect accuracy based on magnetic field resulting from different positions inside or outside the motor. The model is established based on COMSOL finite element simulation to explore the optimal placement position of the micro magnetic field sensors in the motor. Several typical abnormal conditions such as the fault of stator winding inter-turn short circuit and three-phase current unbalance are set up to simulate the magnetic field variation when the motor failure is occurred. The wavelet transform is used to analyze the magnetic field intensity and phase variation at different positions of the motor cross section under the above conditions. Based on the signal variation law and time, the placement position and sensitivity level are obtained, the application of micro sensor in motor fault detection is provided.