An Improved Fault Tolerant Converter Topology for Field Oriented Controlled Induction Motor Drive

A fault tolerant converter topology to mitigate open-circuit and short-circuit faults in the inverter fed induction motor drive using field oriented control (FOC) is proposed in this paper. The proposed converter consists of a current controlled 3-level boost converter to increase the dc-link voltage at the 2-level inverter during pre-fault and post-fault to meet rated load conditions of the induction motor and also to balance the capacitor voltages at the dc-link. Experimental results are presented for open-circuit and short-circuit fault of power devices in a 2-level inverter leg and also post-fault operation. The results of the 3-level boost converter fed induction motor drive combination shows the merits and also compared with fault-tolerant converter (B4) topology and conventional converter (B6) topology.