Failure Analysis of Irreversible Demagnetization of Permanent Magnet Synchronous Motor

Permanent magnet synchronous motors (PMSMs) are widely used in different fields due to their significant advantages such as simple structure, stable operation, high efficiency and diverse shapes, but also because of their unique permanent magnet structure, the motors are at risk of irreversible demagnetization.Firstly, based on the permanent magnet demagnetization curve, the spatial distribution of permanent magnet demagnetization under different operating temperatures and currents is analyzed. Subsequently, the monitoring line is employed to analyze the differences in demagnetization of the permanent magnet at the local position. Finally, a demagnetization fault model is established by utilizing the finite element method. The influence of permanent magnet demagnetization faults on the radial airgap magnetism and torque of the motor is analyzed to obtain the rules of the influence of different degrees of permanent magnet demagnetization on the motor's performance, thus providing a basis for the rapid and accurate diagnosis of permanent magnet synchronous motor demagnetization faults.