Capacitor size reduction of MMC-based STATCOM for medium voltage power distribution network

This paper presents the capacitor size reduction of a MMC-based transformer-less STATCOM for medium voltage ac distribution system. The instantaneous power swinging flows into the single-phase configuration results in a high capacitance needed; however, by accepting the swinging voltage in the capacitor, the capacitance can be drastically reduced. This paper analyzes the dimensional size reduction of this method and thermal characteristics by using a meta-parameterization technique based on existing film capacitor technologies, and estimates that the dimensional size of the capacitor can be about 34% of the conventional design.