A Fault-Tolerant Switching Scheme for an Isolated DC/AC Matrix Converter

A fault-tolerant scheme is proposed for a multistage isolated three-phase dc/ac matrix inverter (MI-TMI). It comprises a front-end dc/ac converter followed by an ac/pulsating-dc converter and a pulsating-dc/ac converter. The fault-tolerant scheme (FTS) ensures a consistent operation under different fault conditions in any of the three stages of the TMI mentioned previously. A fault-diagnosis scheme is outlined which identifies the source of the converter fault and the impact of when the fault onsets on the inverter is explored. Finally, detailed results on the fault-tolerant switching scheme as well as experimental validation using a fabricated MI-TMI prototype are presented.