High frequency high power DC-DC full bridge converter with zero-current zero-voltage commutation

The full bridge pulse-width-modulated (PWM) converter proposed has functions under nearly zero-current-zero-voltage switching conditions, thus minimizing switching losses. This is achieved by using a DC bus switch and a lossless DC bus snubber circuit, comprising an inductor and two capacitors. The DC bus switch can also be used to isolate the inverter under adverse system operation conditions. A complete circuit analysis and a design procedure are presented. Theoretical results have been verified experimentally on a 1 kW 20 kHz laboratory prototype