A Fault-Tolerant Power Converter With Multi-Switch Fault Diagnosis and Repair Capability for 4-Phase 8/6 SRM Drives

In this article, a modular fault-tolerant power converter for 8/6 four-phase switched reluctance motor (SRM) drives is presented. The proposed converter can work for both open-circuit (OC) and short-circuit (SC) fault conditions in the power semiconductor switches. A semiconductor switch module and a relay circuit are used for achieving the fault tolerance feature. The proposed converter is modular and provides independent fault-tolerant control for all phases. It also uses a minimum number of switches when compared with other fault-tolerant converter topologies. The proposed converter is tested for a fault in single as well as multiple phases using MATLAB/Simulink software and is validated experimentally on a 0.6 hp 8/6 SRM using an FPGA-based hardware setup developed in the laboratory. Detailed results are presented and compared with existing fault-tolerant converter topologies. A fault repair time of 2 ms has been achieved for both open and SC faults.