A New Step-Up DC/DC Converter with Soft-Switching Performance and Very Low Voltage Stresses

In this paper, a new single-switch high step-up DC/DC converter with fully soft-switching performance and low input current ripple is presented. The introduced topology utilizes a Three-Winding Built-In Transformer (TWBIT) with a lowpassing current level, along with voltage multiplier cells to reach a very high voltage gain ratio. In this converter, because of the transinverse feature, very high voltage gains can be created under a low number of turns ratio of the TWBIT. The single power switch in this structure operates under Zero Current Switching (ZCS). Also, the voltage stress rate of the power switch in this circuit is limited by a clamp circuit. Due to the unique structure of this circuit, very low voltage stresses are imposed across the switching components. Also, to further improve the converter's efficiency, a resonant cell is considered without additional components. Furthermore, the quasi-resonant performance helps alleviate the reverse-recovery issues of the circuit diodes. The operational principle and steadystate analysis of the proposed converter are discussed thoroughly. Finally, to verify the analytical results, a 200 W sample prototype (25 V / 400 V/ 50 kHz) is implemented in the laboratory.