Investigation of a Fault-Tolerant Control Method for a Multiport Dual-Stator Doubly Salient Electromagnetic Machine Drive

A novel fault-tolerant inverter topology of the multiport dual-stator doubly salient electromagnetic machine (MDDSEM) drive is proposed in this paper for high reliability applications such as automotive and aerospace industries. The proposed topology adopts four diverter switches to reconnect the floating phase windings under the fault conditions and reconfigures the dual inverter to be a five-leg inverter; the output performance could be maintained after a single-phase open-circuit or short-circuit fault of the dual inverter. Compared with the traditional fault-tolerant method of the dual inverter for the MDDSEM, the lower cost and smaller volume of the proposed fault-tolerant system can be achieved. The operation principle and the optimized commutation method of the five-leg inverter for the MDDSEM are analyzed to eliminate the unexpected phase current drop so that the torque performance in the fault-tolerant mode could be improved. The effectiveness and feasibility of the proposed fault-tolerant topology and control strategies are verified by the simulation and experimental results of a 24/16-pole MDDSEM that includes both steady-state and dynamic processes with the standard angle control method and the advanced angle control method.