A non-isolated high step-up hybrid resonant converter based on hybrid transformer

Abstract

A non-isolated high step-up hybrid resonant converter based on hybrid transformer is proposed to recycle leakage energy without any auxiliary clamp capacitor. A resonant capacitor delivers energy from input to output, which reduces the stored inductive energy of the hybrid transformer. Thus, a small size of magnetic core is adopted with high magnetic utilization. Additionally, the input current ripple is reduced due to the resonant operation. Moreover, zero voltage switching (ZVS) turn-on for upper switch and zero current switching (ZCS) turn-on for lower switch are realized to decrease the switching losses. In addition, the output diode turns OFF in ZCS operation, which alleviates the diode reverse recovery problem. Finally, the experimental results of a 240W prototype verified the converter feasibility.