A Collaborative Design of Fault Tolerance and Flux Intensifying Effect to Effectively Improve High Reliability of the PM Drive System

Improving fault-tolerant performance and sensorless operating performance is an effective way to enhance the reliability of permanent magnet (PM) motor system. Typically, good fault-tolerant capacity is achieved by fractional slot concentrating windings (FSCWs) while good sensorless operating performance is obtained by obvious flux-intensifying effect. However, since the FSCWs design and slot–pole combination of fault-tolerant motor weaken the flux-intensifying effect, the improvement of the fault-tolerant performance and the sensorless operating capability are mutually restricted. Also, the design guidance of PM motors considering fault-tolerant and sensorless operating collaborative design is still absent. Therefore, this article first studies a collaborative design method of fault tolerance and flux-intensifying effect to improve high reliability. Based on the analysis of the tradeoff and constraints between fault tolerance and sensorless operation, three flux-intensifying fault-tolerant motors are developed and compared. With the analysis of the influence of key parameters on the performance of fault tolerance and sensorless capacity for these three motors, the design criteria are obtained. Finally, the rationality and validity of the proposed design method are verified through simulation analysis and experiment tests.