A new non-isolated high step-up converter with reduced voltage stress

This paper presents non-isolated high step-up converters with reduced voltage stress. Based on the conventional flyback converter, a high step-up converter is derived. The voltage stresses of the switch and diodes are limited by using a clamping diode and voltage doubler structure. Also, to further reduce the voltage stresses of them, another high step-up converter is proposed. The proposed converter has one additional capacitor to serve as a doubler capacitor. By using this capacitor, the voltage stresses of the switch and diodes can be clamped to the lower voltage from the boost converter. The operational principle, analysis and design considerations of the proposed converter are presented in this paper. The validity of this study is confirmed by the experimental results from 24V input and 250V/125W output prototype.