Boosting the Efficiency of Low Voltage Modular Multilevel Converters beyond 99%

  • Author:

    Johannes Kolb, Felix Kammerer, Philip Grabherr, Mario Gommeringer, Michael Braun

  • Source:

    PCIM Europe 2013, Nuremberg, Germany

  • Date: 14.-16.5.2013
  • The Modular Multilevel Converter (MMC) is an upcoming topology for high efficiency power
    conversion not only in the high voltage range but also for low voltage applications. This contribution
    presents several improvements in the hardware design, control and modulation of a low
    voltage MMC to increase the efficiency over 99%. Simply standard Silicon-MOSFETs and no
    SiC- or GaN-transistors are used as semiconductor switches in the prototype converter. The
    detailed analysis of the efficiency also shows an excellent performance in the low power range,
    which yields to a very flat efficiency curve. Therefore, the MMC is especially suited for grid
    connected inverters, e. g. in applications like DC microgrids, photovoltaics etc.