Fault-Tolerant SRM Drives—A Review

Fault tolerance in electric motor drives has been extensively studied due to their widespread usage in safety-critical applications, including more/all-electric aircraft and electric vehicles. Switched reluctance motors (SRMs) are renowned for their high robustness and excellent fault tolerance. However, they are not immune to faults, and a potential fault in any part of the motor drive could have serious implications for the system, even may lead to unexpected shutdown if the fault is not promptly remedied. The power converter is a key component and the most vulnerable to failure, as reported for 35% of the drive faults. Fault tolerance has typically been achieved through a combination of hardware and software reconfigurations. However, due to the simple structure of the standard asymmetrical half-bridge converter, hardware reconfiguration is more commonly used to remediate converter faults. Consequently, fault tolerance adds cost and complexity to a standard SRM drive system. This article presents an instructive survey of the recent research on fault-tolerant SRM drives. Moreover, the postfault performance, implementation costs, and fault-tolerant capabilities of advanced fault-tolerant converters are systematically quantified, evaluated and compared. Finally, the article is concluded with an investigation on the future research trends in fault tolerance in SRM drives.