Designing LLC resonant converters for optimum efficiency

This paper presents a novel design methodology for the tank circuit of LLC resonant converters, based on a simplified yet accurate model of the steady-state operation in the “below-resonance” region. This model is used in a design strategy that aims to design a converter capable of operating with soft­switching in the specified input voltage range, with a load varying from zero up to the maximum specified level, with minimum reactive energy and, then, maximum efficiency level.

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