High gain non-isolated current-fed half-bridge partial series resonance pulsed based zero current switching voltage quadrupler

This paper proposes a novel non-isolated current-fed voltage quadrupler using series LC resonant circuit for soft-switching in high voltage gain applications. The proposed topology employs a half-bridge current-fed converter at the source and a voltage-quadrupler at the load. The proposed converter enables soft-commutation of the semiconductor devices at turn-off owing to the partial resonance pulse produced during the overlap conduction time, which causes natural zero current commutation before the gating signal is turned-off. It eliminates the traditional turn-off voltage spike and avoids the traditional requirement of the snubber across the devices in current-fed circuits. In addition, partial resonance reduces the peak and circulating currents and so the conduction loss in the devices is minimized. Variable frequency modulation with fixed duty cycle is employed to achieve the zero-current switching (ZCS) operation over wide range of load and input variations with load regulation and high efficiency. Simulation results are reported using PSIM11.1.64 for validating the proposed converter operation, analysis and design. A rated load efficiency of 97.2% is obtained showing 3% improvement compared to hard-switching converter.