A new soft recovery PWM quasi-resonant converter with a folding snubber network

A new soft recovery (SR) quasi-resonant converter (QRC) having a multiple-order folding snubber network(MFSN) is introduced. It is obtained by combining a normal QRC with a folding snubber network of which the surrounding components are composed of passive devices only (diodes and capacitors). The reverse recovery loss of the main rectifier diode is eliminated by this method utilizing multiple resonance with a multiple-order folding snubber network. By realizing soft switching conditions, the proposed converter has pulsewidth modulation capability with high efficiency and is suitable for high-voltage and high-power dc to dc converter applications.