Automatic fault diagnosis of fault tolerant power converter for switched reluctance motor based on time-frequency technique

The concept of fault tolerance device and implementation of the automated algorithm based fault detection plays an important role in the reliable operation of rotating machinery. This paper looks at fault tolerant power converter failure detection in three-phase 6/4 switched reluctance machine (SRM) through the use of time-frequency technique for the detection of power switch open-circuit failure. A fault tolerant power converter with redundancy and specific winding connections has been proposed for a three-phase 6/4 switched reluctance machine in order to add fault tolerant capacity to a standard three-phase SRM converter and also for improving the reliability of motor. This is achieved by using a dual converter on a common power supply with six isolated phases. The power converter model is built up in CIRFLU using Flux 2D´s electrical circuit and linked to the finite elements method (FEM) model of the SR machine. Power switch open-faults occurrences in a fault tolerant power converter are considered and the effect on the electromagnetic torque signal is analyzed using various time-frequency representations (TFR). The results prove the efficiency of the proposed approach in automatic detection and localization fault in power converter phase. Simulation results are presented and well discussed.