Modular design of soft-switching circuit for two-level and three-level inverters

This paper presents a modular design concept for soft switching inverter systems. A novel resonant circuit is proposed and designed as an optional module to a conventional inverter. By attaching the resonant module, the conventional hard-switched inverter can be converted to a soft-switched inverter. New features include modularity, reduced component count and low device voltage ratings. The basic resonant module works for two-level inverters. The modularity approach can also work for three-level inverters using two mirrored resonant modules