A New Active Clamp Quasi-Resonant High Step-Up DC/DC Converter Based on Built-In Transformer With Low Voltage Stress

This article presents a new wide voltage gain dc/dc converter with low input current ripple. This topology uses a built-in transformer (BIT) with a low current level and voltage multiplier cell to reach high voltage gains under appropriate duty cycles. In this circuit, an active clamp circuit absorbs the energy of the leakage inductor from the BIT and delivers it to the output, thus, the zero voltage switching conditions at turn-<sc xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">on</small> time are achieved for both switches. Due to the unique structure, very low voltage stresses are applied across the semiconductor components of the proposed circuit. In this circuit, a quasi-resonant performance in the main mode of the converter is considered to alleviate the switching power loss. Moreover, all diodes operate without reverse-recovery issues. Therefore, high voltage gain, low input current ripple, soft-switching performance, and low magnetic current stress are merits of the proposed converter, which helps to obtain enough high efficiency for the proposed circuit. The operational principle and steady-state analysis of the proposed converter have been analyzed in detail. Finally, a 25 V/400 V output, 200 W prototype with an efficiency of 96.3% is implemented in the laboratory to verify the analytical results.