A pulse-width modulation zero-voltage-zero-current switched half-bridge quasi-resonant converter

The authors describe a novel half-bridge quasi-resonant converter, which is regulated by pulse-width modulation, in contrast to the frequency modulated half-bridge quasi-resonant converters reported in the literature. The concept of zero-voltage-zero-current switching is proposed. It provides commutation under zero current in a switch of the inverter leg and under zero voltage in the other one. The operating principle, design-oriented analysis, design procedure, simulations, and experimental results are presented. As a consequence of constant frequency operation, the proposed converter is easier to design and control than the well-known resonant converters or the half-bridge quasi-resonant one, regulated by frequency modulation