Fault Tolerant Three-Phase AC Motor Drive Topologies: A Comparison of Features, Cost, and Limitations

A．Switch-Redundant Topology An early attempt to add fault tolerant capacity to a standard three-phase inverter topology for induction motors was presented．This topology will be referred to as the switch-redundant topology and is shown in Fig.5．This topology incorporates four TRIACs or back-to-back connected SCRs and three fast acting fuses．The fuses are connected in series with the load phases．Since this topology is a combination of topologies and control methods to accommodate an opened phase，and a shorted switch，they will be considered separately．