A Fault-Tolerant Scheme Against the Open-Switch Failure in Open-End Winding PMSM System With Isolated DC bus

This letter proposes a fault-tolerant scheme against the open-switch failure for the open-end winding permanent-magnet synchronous machine (OW-PMSM) system with isolated DC bus. With the proposed scheme, the reference voltages in three-phase stationary coordinate system are shifted synchronously to adapt the output voltage characteristic of the system in fault state. Further, to reduce the switching losses, the modulation process is designed based on the polarity of reference voltages. The performance of the proposed modulation scheme is experimentally validated.