Fault-tolerant oriented control of modular linear switched-flux permanent magnet machine

This paper proposes a fault-tolerant control strategy for three phase linear switched-flux permanent magnet machine (LSFPMM) with modular structure, which has one-phase open-circuit fault. Under this condition, this three-phase LSFPMM has a novel perspective of the operating principle similar to two-phase machine. Based on finite element analysis (FEA), the performance of proposed fault-tolerant control strategy has been simulated. The predicted results show the fault-tolerant control strategy can effectively keep average thrust force and thrust ripple virtually unchanged after fault occurance. In addition, the influence of module gap on fault-tolerant performance has also been investigated. The larger module gap tends to improve fault-tolerant performance due to lower mutual inductances between phases, but decrease average force simultaneously. The proposed fault-tolerant control strategy can also be extended to other three-phase machines.