Experimental Assessments of a Triple Redundant Nine-Phase Fault-Tolerant PMA SynRM Drive

Fault-tolerant machine drives are key enabling technologies in safety critical applications. The machine drives are expected to exhibit high performance in healthy conditions and accommodate as many faults as possible, namely open circuit or short circuit in the machine and inverter or even an interturn short circuit. This paper aims to assess a triple redundant nine-phase (3 × 3-phase) permanent magnet assisted synchronous reluctance machine (PMASynRM) drive by comprehensive experimental tests under both healthy and fault conditions on a 35 kW machine drive prototype. The healthy performance, fault behavior, fault detection, and mitigation strategy are presented and assessed by extensive tests which demonstrate that the machine drive exhibits high performance and excellent fault tolerance with simple and cost-effective implementation. Therefore, the proposed machine drive has proven to be a practical candidate for safety critical applications.