11kW, 70kHz LLC Converter Design with Adaptive Input Voltage for 98% Efficiency in an MMC

  title={11kW, 70kHz LLC Converter Design with Adaptive Input Voltage for 98\% Efficiency in an MMC},
  author={Roland Unruh and Frank Schafmeister and Joachim B{\"o}cker},
  journal={2020 IEEE 21st Workshop on Control and Modeling for Power Electronics (COMPEL)},
Although there are numerous design methodologies for the LLC resonant converter, they often do not consider the possibility of input voltage adjustment. In the proposed concept, a modular multi-level converter (MMC) is used to step-down the three-phase medium voltage of 10 kV, and provide up to 1 MW of pure DC power to the load consisting of electrolyzers for hydrogen generation. Therefore, each module is extended by an LLC resonant converter to adapt to the specific electrolyzers DC voltage… 
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  • Hang-Seok Choi
  • Engineering
    APEC 07 - Twenty-Second Annual IEEE Applied Power Electronics Conference and Exposition
  • 2007
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