Abstract:The interleaving technique is an effective method to improve the output capability of the power module. Small differences in parameters of the resonant cavity can cause serious uneven current in the interleaved LLC resonant converter. In this paper, by introducing an active switch in the rectifier of LLC resonant converters, a hybrid rectifier was built, and the auxiliary control on the rectifier was used to actively compensate the voltage gain of the module with smaller output current, thereby achieving the current sharing control of the interleaved LLC resonant converter. The working principle and characteristics of the LLC resonant converter with hybrid rectifier were analyzed in detail, and different implementations of the current sharing circuit were given according to specific applications. Finally, the experimental results verify the feasibility and effectiveness of the proposed current sharing control method.
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