Reduced Capacitor Size and On-State Losses in Advanced MMC Submodule Topologies

Progress of high power Modular Multilevel Converters (MMC) is of prime importance for many future applications [1]–[5]. Further reduction of power losses and smaller foot-print of the converters requires advanced submodule topologies, well adapted to SiC-power semiconductors and the operating conditions in MMC. The high potential of these measures is investigated and explained using analytical methods – providing general insight. Numerical results, based on commercially available Si- and SiC-modules are presented, demonstrating the essential improvements compared to the state-of-the-art.