High step-up DC/DC converters based on coupled inductor and switched capacitors

Abstract

This study proposes a series of high step-up DC/DC converters based on the coupled inductor and switched capacitors. The priority of the switched capacitor connection methods of the converters is presented by their contributions to the voltage gain so that the converters can be selected optimally according to the gain demand. For this converter, the voltage gain can be adjusted by both of the turns ratios of the coupled inductor and the number of switched-capacitor units. It makes it possible to further improve the voltage gain when the turns ratio of the coupled inductor is rather high. Moreover, the introduction of switched capacitors can reduce the voltage stress of power components. In this study, the operating principle and performance characteristics of the converters are analysed. Also, a 300 W prototype is set up for verification. The experimental results demonstrate the effect of the theoretical analysis and superiority of the converter.