Ultrahigh Step-Down ZVS Buck Converter With Continuous Output Current

This article proposes a new soft-switched two-phase high step-down dc-dc converter. The proposed structure applies series capacitor and coupled inductor techniques. This combination can reduce the converter's voltage gain considerably. In addition, the proposed converter comprises only two switches and two sets of coupled inductors, all participating in the power conversion process and are responsible for reducing voltage gain. Not only do the coupled inductors decrease the conversion ratio, but also, they cancel out the ripple of each other. Therefore, the continuous low ripple output current is achieved. Moreover, both output diodes contribute to providing the output current. Furthermore, zero voltage switching is attained for both switches. A 120-W prototype converter is implemented, and the experimental results justify the theoretical analysis.