Four-leg based Matrix Converter with Fault Resilient Structures and Controls for Electric Vehicle and Propulsion Systems

A study of four-leg based fault-tolerant matrix converter is presented for remedial topological structures and control techniques against both open-faults and short-faults occurring in the AC-AC matrix converter drive based electric vehicles and propulsion systems. Topologies of the matrix converter drives with additional backup leg have been proposed to allow the matrix converter based drives for tolerating both open and short phase failures. Switching function algorithms with closed form expressions, based on switching matrices, have been developed to provide the matrix converter drives with continuous and disturbance-free operation after opened phase faults and shorted phase failures. The developed switching function matrix and modified topological configuration allow to synthesize redefined output waveforms under open-switch, open-phase, and shorted load motor winding faults. In addition, the proposed matrix converter topology can produce three-phase balanced sinusoidal output currents even after short-switch failures. Simulation and experimental results show the feasibility of the proposed topologies and the developed switching function techniques in case of both the open and short faults.