Active common-mode voltage reduction in a fault-tolerant three-phase inverter

A fault-tolerant topology in a three-phase four-leg inverter which is capable of reducing the common-mode voltage (CMV) during the post-fault condition is presented. The CMV during both post-fault and pre-fault is investigated. This paper proposes a topology to reduce the common-mode voltage during pre- and post-fault operation of the inverter by using the healthy switches. The accompanying simulation results verify the common-mode current reduction during the fault period.