**2. Fault diagnosis methods**

SRM drives are known to be fault-tolerant by their nature but not completely fault-free. Opencircuit faults are a common fault type of the motor drive, leading to starting difficulty, overcurrents, high torque ripples, and reduced load capacity [13, 14]. Due to the harsh condition EVs/HEVs operate at, the switching devices can easily break down. In this section, the fault characteristics of SRM under open-circuit are illustrated; and the fault diagnosis strategy is also presented.
