Six-phase fault-tolerant permanent magnet motor drives with reduced switch counts: Topology comparisons and hardware demonstration

This paper investigates fault-tolerant PM machine drive converter topologies that seek to minimize the number of switches while retaining as much of their original pre-fault performance capabilities as possible. Four six-phase drive topologies have been selected and compared with conventional half-bridge and full-bridge converters. All four topologies use fewer half-bridge phase-legs than the baseline cascaded full-bridge topology. The selected six-phase converter topologies are evaluated to compare their switch parts count and post-fault performance. Experimental tests are conducted with a prototype 6-phase PM machine using the candidate converters to confirm their fault-tolerant performance characteristics.