A fault-tolerant switching scheme for a high-power high-frequency-link inverter

A modulation-based fault-tolerant switching scheme (FTSS) is outlined for an isolated high-frequency-link (HFL) inverter. It comprises a front-end Dc/pulsating-Dc converter followed by an Ac/Ac converter. At first, the lost phase in the Dc/Ac Converter is identified based on the type of distorted output line voltages and then modulation references are changed accordingly so as to restore the output line voltages. The proposed FTSS ensures operation under different types of fault conditions in the front-end Dc/pulsating-Dc converter without redundant circuits. Detailed results on the switching scheme as well as experimental validation using a fabricated prototype are presented.