Novel High Step-Up Soft-Switching DC-DC Converter Based on Switched Capacitor and Coupled Inductor

A novel high step-up dc-dc converter with coupled inductor and switched capacitor is proposed in this article. The proposed converter adopts capacitors charged in parallel and discharged in series with a coupled inductor to achieve high step-up voltage gain. By utilizing the energy stored in the leakage of the coupled inductor, both of the switches can realize zero-voltage switching, which can reduce switching loss and improve efficiency. In addition, the voltage stress of the switches and diodes are also reduced. Therefore, low voltage components can be utilized and the input current is continuous. The operating principle, steady-state, and parameter design are shown in details, and a 100-W experimental prototype with 25-V input voltage and 380-V output voltage is established in the laboratory to verify the feasibility of the proposed converter, and the highest efficiency is 96.21%.