Multiphase Current Imbalance Localisation Method Applied to Natural Fault- Tolerant Strategies

Abstract

Multiphase machines are interesting options for high-reliability applications due to their inherent fault tolerance against open-circuit faults (OCFs). Moreover, if the regulation of the x-y currents is realized in open-loop mode using virtual voltage vectors (VVs), the mandatory post-fault control reconfiguration is avoided. The new reconfiguration-less approach was recently defined as a natural/passive fault-tolerant strategy, offering good prospects for industry applications. This work extends the idea to the fault detection (FD) procedure and suggests new settings for the current imbalance localization (CIL) method. The proposal is based on the vector space decomposition (VSD) approach that allows the joint detection of OCFs and stator resistances dissymmetry (RDs). Experimental results in a five-phase induction motor (IM) drive using VVs confirm the viability of the technique.