Design of Integrated Transformer and Inductor for a High-Power High-Frequency Resonant Converter

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 makes up a large portion of the total converter volume. This paper presents a comprehensive design procedure for a 100kHz, medium-voltage transformer to be used in a 30kW Serial Half Bridge converter with 45kW overload condition. Parallel windings are used to allow for high-current high- frequency applications and current sharing is analyzed. Also, a method for leakage inductance integration is also discussed in this paper.