High step-down dc-dc converter with low voltage stress and wide soft-switching range

In this study, the integration of buck converter with Cuk converter to achieve a non-isolated high step-down dc-dc converter is investigated. Also, a soft-switching cell is modified and used in the integrated converter to provide zero current switching and zero voltage switching condition for the converter switches at turn-on and turn-off, respectively. The auxiliary cell also eliminates the reverse recovery problem of the converter diodes. As a result, a high efficiency high step-down converter with reduced voltage stress for semiconductor components is derived. The analysis, operational principle and design considerations of the proposed converter are discussed in this study. The accuracy of the converter operation is verified by a 200 W, 155 V-to-24 V laboratory prototype.