Two-phase interleaved LLC resonant converter with current-controlled inductor

Multi-phase interleaved converters represent interesting solutions in terms of reduced current rating of each module, reduction of input and output current ripples, and possibility of redundancy. However, when attempt to interleave resonant converters operating at the same switching frequency, the resonant components' tolerance can cause severe current unbalance between them. In this paper, a two-phase interleaved LLC resonant converter is proposed that employs a current-controlled inductor to adjust the resonance frequency of one module, thus compensating for component mismatch. Experimental results of a prototype rated at 24V-12A output are presented, confirming the theoretical forecasts.

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