Current Fed Resonant Dual Active Bridge Converter with Dual Source Property for CC-CV Charging

This paper presents a current-fed resonant dual active bridge converter, suitable for battery charging application. It is capable of operating as a current source and a voltage source by utilizing the load independent characteristics of the resonant converter with single step change in frequency and ensures soft switching for all the switches. Thus, it offers high efficiency through-out the operating range. Additionally, it eliminates the problem of input current ripple and replaces the bulky short-lived electrolytic capacitor that improves the size and life of the converter thereby enhancing its suitability as a converter for battery charger. The operation of the converter under steady state in each mode is discussed. A scaled down laboratory prototype is developed and its performance is validated in constant current and constant voltage mode.