Fault tolerant control of a PMSM drive in the selected emergency conditions

The paper describes an investigation of fault tolerant control strategies for permanent magnet synchronous motor (PMSM) driven by a fault-tolerant inverter. The inverter is a topology-modified inverter with fault-tolerant capability, which can be configured as the standard 3-phase 6-switch inverter and reconfigured as 3-phase 4-switch or 2-phase 4-switch inverter under the fault condition. By analyzing operating principle of a fault-tolerant inverter and the mathematical model of PMSM, fault tolerant control algorithms are investigated. There is a conclusion that three phase stator windings of PMSM can be effectively operated by controlling only two phase currents. Simulation results show the validity of the proposed methods.