Interleaved Zero-Voltage Switching High Step-Up DC-DC Converter Using a Single Auxiliary Switch

A novel interleaved zero-voltage switching high step-up DC-DC converter using a single auxiliary switch is proposed in the paper. The circuit configuration is based on an interleaved boost converter integrating a coupled-inductor-based voltage multiplier cell and a zero-voltage switching (ZVS) auxiliary circuit, so that the converter can obtain high voltage gain without extreme duty ratio and achieve zero-voltage switching for both main switches. The voltage stresses of power devices are lower to reduce the conduction losses. The auxiliary switch can achieve zero-current switching (ZCS) to reduce the switching losses. The interleaved operation reduces the input current ripple. The reverse recovery problem of the diodes is alleviated by the leakage inductances of the coupled inductors. The operating principle and steady-state analysis of the proposed converter are expressed in detail. Finally, a 1000W prototype is developed to validate the proposed converter feasibility and performance.