An isolated full bridge boost converter with active soft switching

Isolated full bridge boost converter is attractive in single-stage Power Factor correction(PFC) with isolation requirement,but the major disadvantage is that the transformer leakage inductance causes high transient voltage across the bridge switches,which increases the switching rating and decreases the reliability.In this paper,an active soft switching circuit is proposed for the isolated full bridge boost converter.The proposed soft switching circuit clamps the voltage across the full bridge,transfers the energy in the leakage inductance to the load,and provides zero voltage turn-off for all the main switches.Furthermore,the auxiliary switch features zero current turnon and zero voltage turn-off.Therefore,the efficiency is improved.The simulation result is present at last.