An Interleaved Diode-Capacitor High Step-Up Quasi-Resonant DC-DC Converter Featuring Soft-Switching Characteristic

In this paper, a high step-up quasi-resonant dc-dc converter, based on an interleaved diode-capacitor structure, is introduced and analyzed. High voltage gain is obtained by the use of a diode-capacitor network. Soft switching condition, which includes zero-current switching (ZCS) or zero-voltage switching (ZVS), is resulted for all semiconductor power devices by quasi-resonance technique created by input inductances of the converter along with snubber capacitors across the switches. Reverse recovery problem of diodes is alleviated because of ZCS condition. Then, the switching losses have been reduced considerably and the converter efficiency is improved. With soft switching characteristic, switching frequency can be increased and subsequently the capacity of the passive components is decreased. Also, the voltage stress of power switches is reduced by the series-connected topology in the high-voltage side. Finally, the presented simulation results verify the features of the proposed topology.