A Three Coordinated Power Channels LLC Converter With Ultrawide Voltage Range

Abstract

To achieve ultrawide output voltage range, this paper proposes a novel isolated LLC resonant converter with three coordinated power channels. The proposed converter features three working conditions and encompasses five operation patterns, allowing for the adjustment of quality factor for a wider gain range. With more power channels, the converter can reduce the stress of the resonant tank and switches to further improve the higher power level and achieve the soft switching. To ensure smooth gain transition and a wider gain range, the turns ratio of the transformer is designed by considering three different conditions. Finally, a 1 kW prototype was built to verify the effectiveness of the proposed topology. The results confirm the eight times output voltage range of the converter and a peak efficiency of 96%.