Design Optimization and Planar Magnetics Integration of Three-Phase Interleaved LLC Resonant Converter

This paper proposes an optimization method based on three-phase LLC converter. The effective value of the primary and secondary currents is solved through numerical calculation methods, and then combined with the gain curve of the converter, the resonant parameters with the minimum current effective value that meet the gain range can be calculated. In addition, a magnetic integrated structure was proposed, based on which the inductor turns, loss, and footprint are optimized. Finally, simulation and experiment were conducted, and a 2kW prototype was implemented with an efficiency of 97.3% and a power density of 200 W/in³.