Magnetizing inductance assisted wide range ZVS three-phase AC link current-fed Dc/Dc converter with active-clamp for low DC voltage applications

This paper explains steady-state operation and presents steady-state analysis and design of a three-phase AC link active-clamped zero-voltage switching (ZVS) current-fed dc/dc converter. The proposed converter maintains ZVS of all power semiconductor devices over wide range of load and supply voltage, achieved by the energy stored in the boost inductors for auxiliary clamp devices, and leakage inductance (aided by magnetizing inductance) for main devices. The proposed converter also combines the advantages of three-phase configuration with zero-current switching (ZCS) of rectifier, making it a competitive topology in the area of power supplies/converters especially for low voltage dc sources with high voltage amplification ratio. Simulation and experimental results are illustrated for wide variations in input voltage and load on a tested 300 W prototype.