A constant frequency resonant DC/DC converter with zero switching losses

Abstract

A new resonant DC/DC converter topology which operates at a constant frequency and exhibits near zero switching losses is presented. The resonant circuit employed in the converter consists of a series branch and a parallel branch. The components of the series branch are tuned at the operating frequency of the converter. The components of the parallel branch are, however, tuned at a frequency much higher than the operating frequency of the converter. Four capacitors are placed across the switches of the full-bridge. The proposed resonant components shapes the current and voltage waveforms in the converter circuit in such a way that near zero turn-on, turn-off, and snubber losses are obtained while maintaining low voltage stresses across the inverter switches and rectifier diodes. A detailed description of the converter circuit, explaining the operating principle is given.<>