Study on Permanent Magnet Synchronous Demagnetization Fault Performance

The relationship of permanent magnetic material characteristic parameters was analyzed, and a simulation method of a permanent magnet synchronous motor (PMSM) rotor demagnetization fault was put forward. Based on this, a simulation model of the PMSM under partial demagnetization and uniform demagnetization fault were established, and different degrees demagnetization fault was simulated. Relationship between output torque and initial phase was gained by applying different initial angle current excitation source in order to establish the reasonable simulation model. Simulation results show that magnetic field strength and output torque get smaller and smaller with increasingly fault severity. The magnetic field asymmetry of PMSM partial demagnetization is more and more serious with increasingly fault severity, and the magnetic field scale of PMSM uniform demagnetization decreased significantly. The harmonic analyses using Fast Fourier Transform (FFT) show that the fault diagnosis method based on the harmonic wave analysis is only suitable for partial demagnetization fault of the PMSM, and not apply to uniform demagnetization fault of the PMSM