A new quadratic step-up DC-DC converter with low voltage and current stresses

This study proposes a new coupled-inductor-based high step-up DC-DC converter characterized by low voltage and current stress. The use of a coupled inductor (CI) in combination with voltage multiplier cells enhances the voltage gain of the proposed structure. In this topology, the vertical structure results in very low voltage stress across all semiconductor components. Moreover, current sharing between the coupled inductor and the input inductor reduces power dissipation in the magnetic components of the proposed converter. In this circuit, a quasi-resonant cell is employed to reduce switching power loss during turn-off. Additionally, regenerative passive clamp circuits absorb and recycle the energy stored in the leakage inductance of the coupled inductor (CI), thereby limiting the voltage stress on the switches, which operate under simultaneous switching conditions. Therefore, the proposed circuit provides a high voltage gain ratio, low voltage stress, and low current stress, contributing to high efficiency. Detailed presentations of the operational principle and steady-state analysis of the introduced structure are included. The topology's effectiveness is validated by experimental results obtained from a 200 W laboratory prototype operating between 25 V and 400 V.