Fault Tolerant Operation of an LCI and VSI fed Hybrid Induction Machine Drive for Medium Voltage High Power Applications

The fault tolerant operation of the drive is a critical requirement in medium voltage high power applications. In these drives, at an event of converter failure, a continuous operation with reduced power rating is preferred over a complete shutdown of the system. Hence, multi-phase machines are widely used for such applications since they offer inherent fault tolerance operation. This paper proposes a new fault tolerance and on-the-fly re-connection algorithm for an LCI and VSI fed multi-phase induction machine drive. The proposed method offers continuous operation of the drive with half the rated power when an LCI is faulty. The proposed algorithm is experimentally validated on a 75 kW multi-phase induction machine drive and the results are presented.