Optimal Design of Resonant Network for CLLC Resonant Converter

The dc transformer based on CLLC resonant converter is widely researched in the dc microgrid due to its excellent bidirectional power transfer capacity. Many resonant network design methods assume that the resonant current is constant during the deadtime. It may lead to hard switching or large conduction loss. Besides, the effects of deadtime on soft switching have not been closely analyzed. This article proposes an optimized design method to minimize conduction losses while achieving zero voltage switching, and it can easily obtain the optimal region and deadtime selection range. Parametric design and deadtime selection principles are derived based on the time-domain models, and then the design method and corresponding procedure are developed. Finally, a 4-kW 500-kHz CLLC resonant converter prototype is built to verify the feasibility of the proposed optimal design method.

Automated summary

This article proposes an optimized design method for the dc transformer based on CLLC resonant converter, which minimizes conduction losses while achieving zero voltage switching. Parametric design and deadtime selection principles are derived based on the time-domain models, and the corresponding design method and procedure are developed.