Research on Fault Characteristics of Direct-drive Permanent Synchronous Motor with Stator Winding Inter-turn Short Circuit Fault

As inter-turn short circuit fault (ISF) in a direct-drive permanent magnet synchronous motor (DDPMSM) degrades its reliability and may cause serious catastrophes, fault detection, fault diagnosis and fault-tolerant control for the DDPMSM are necessary. The fault characteristics of DDPMSM with ISF are the basis of fault detection, fault diagnosis and fault-tolerant control. Hence, in this paper, the fault characteristics of DDPMSM with ISF are researched. The characteristic quantities include branch current difference, average electromagnetic torque, two harmonic electromagnetic torque and torque ripple. First, the structure and key parameters of the DDPMSM are reported. Then, the influences of ISF position and number on fault characteristic are researched. Finally, a prototype of DDPMSM is manufactured, and the experimental results validate the conclusions. This work will provide a significant reference for the fault detection, fault diagnosis and fault-tolerant control of DDPMSM.