Detection and Discrimination of Interturn Fault and High-Resistance Connection Fault in PMSM Based on Deviation Angle of Zero Sequence Voltage

Interturn short fault (ISF) and high-resistance connection (HRC) fault are both common incipient faults occurred in permanent magnet synchronous machines (PMSMs). Due to a different severity of these two faults, in addition to the conventional fault diagnosis, it is necessary to distinguish the fault type, so as to take targeted preventive measures. To ensure the reliability of the PMSM system, a novel method for detecting and discriminating ISF and HRC fault in PMSM based on the deviation angle of zero-sequence voltage component (ZSVC) is proposed in this article. In this method, the amplitude and initial phase angle of ZSVC are both analyzed by an improved phasor tracking algorithm. The amplitude of ZSVC is used to detect the abnormal operation of the PMSM, and the discrimination indicator (DI) is constructed using the phase angle of ZSVC and three-phase current to distinguish these two faults. The simulation and experiments are carried out to verify the effectiveness of theoretical analysis, and the results show that the proposed method has good performance under different operating conditions and fault severities.