Analysis and experimental verification of a single-switch high-voltage gain ZCS DC-DC converter

This study proposes and analyses the integration of soft-switching technique with a single switch, non-isolated, coupled inductor DC-DC converter to achieve high efficiency and high step-up conversion ratio. The topology optimally integrates the coupled inductor and soft-switching technique using a parallel LC resonant tank circuit to maintain zero-current switching (ZCS) for on/off switching. The leakage inductance of the coupled inductor alleviates the reverse-recovery issue of diodes, and diodes can operate under ZCS condition. Moreover, the converter operates in a lower frequency range due to high step-up voltage gain. The principle of operation and steady-state analyses of the proposed converter are presented. A prototype validates the theoretical analysis and demonstrates a higher peak efficiency of 96.43% than the corresponding hard-switched converter.