Optimized switching sequence for snubberless operation of bilateral MCT switches in AC resonant link converters

Abstract

This paper revisits a discrete form of a bilateral switch that is used in AC resonant link power converters (ACRLCs). The active power device used is the MOS-controlled thyristor (MCT). The switch topology offers high levels of component integration, and increases the modular design of ACRLCs. However, the topology can cause problems due to the nonidealities of the solid-state devices. A simple solution to these problems is presented in the form of a switching sequence that allows all switches to theoretically commutate current at zero-voltage. Also, the proposed sequencing of the devices eliminates the need for snubber components. Simulation and experimental results are presented and discussed.