A resonant inductance embedded transformer is a critical component of the LLC resonant converter as it provides the required isolation between the primary and secondary sides and the total transformer volume significantly influences the power density of the whole converter. But current stress increases with the increased power. Therefore, this paper shows an analytical model of the current sharing for parallel Litz wire transformers allowing for high-current high-frequency operation. A matrix transformer with naturally good current sharing is proposed and verified with a 30-kW resonant converter. Besides, a method of leakage inductance integration is also mentioned in this paper.
