A Dual Half-Bridge LLC Resonant Converter with Reduced Output Current Ripple for Wide Output Voltage Range Application

Abstract

This paper proposes a new dual half-bridge LLC resonant converter which can regulate wide output voltage range. The proposed converter uses two operation modes: voltage doubler mode and voltage quadrupler mode. Thus, the proposed converter can regulate wide output voltage range with narrow switching frequency variation by changing operation mode adaptively. Because the operation mode is changed by primary switch gate signal, additional components are not required. Also, the output current ripple across the output capacitor is reduced, because of the high minimum operating switching frequency and hybrid rectifier structure. Therefore, the size of output capacitor is decreased, and the proposed converter can achieve high power density.