ZVS Hybrid Three-level Converter with Low Voltage Stress and Reduced Filter

A novel soft-switching three-level (TL) topology for dc-dc converters is proposed. It is very suitable for high voltage and high power conversion applications. It is essentially a hybrid combination of a half-bridge TL section and a full-bridge section. The main advantages of the proposed converter are as follows: the voltage stress of all switches is ensured to be only the half of the input voltage; the secondary rectified voltage is a three-level waveform having low high-frequency content which can reduce the output filter significantly; the voltage stress of the rectifier diodes is reduced; the input current of the converter has quite little ripple, and as a result, the input filter can also be minimized. A prototype converter has been tested for the verification of the principles and advantages