Soft-switching buck boost converter using passive snubber composed of pulse current regenerative resonant circuit

This paper presents a novel soft-switching buck boost converter using a passive snubber composed of a pulse current regenerative snubber circuit. The proposed soft-switching circuit consists of passive components which configure CD (capacitor and diode) snubber circuit and regenerative resonant circuit assisted with an auxiliary winding of a main inductor. The paper indicates the effective converter operation region of the soft-switching action and its efficiency improvement results on the basis of experimental evaluations using 3.5 kW prototype.