A New Single-Switch Isolated High-Gain Hybrid Boosting Converter

A new single-switch isolated hybrid boosting converter featuring low-component stress, simple control, high efficiency, high power density, and flexible gain extension is proposed in this paper. At the primary side, a new design of energy regenerative snubber is proposed to provide soft-switching condition, suppress voltage spike, and recycle leakage energy. At secondary side, a bipolar voltage multiplier (BVM) structure which enhances the gain boosting capacity, reduces the output ripple, and facilitates fly-back-forward operation of transformer is proposed. Based on this structure, the transformer can deliver energy to the output at both magnetizing and magnetic resetting stages. In addition, the bulky high-voltage-rated output filter capacitor can be eliminated due to the cascaded and autobalanced capacitors in the BVM structure. A 200-W 35- to 400-V prototype is built to demonstrate the feasibility of the proposed topology. The peak efficiency of 93.8% is reached and 91.2% is achieved at rated power.