A fault tolerant control and power electronic for a permanent magnet synchronous motor drive

In this paper fault tolerant solutions for different components of the permanent magnet synchronous machine drive (PMSM) such as digital controller, inverter and feedback sensors are presented. In case of digital controller fault tolerance, three fixed point Digital Signal Processor (DSP) based controllers are used in parallel, running the same control algorithm. In case of fault tolerant inverter, a redundant leg is added, which replaces the faulted leg. Faulted leg isolation and redundant leg insertion is done by using independent back to back connected thyristors. Sensorless vector control algorithm is implemented in case of position sensor failure. A redundant current sensor is used in case of current sensor failure. The fault tolerance of the above system is verified using field oriented control (FOC) of a PMSM drive.