Operating principles of shunt STATCOM based on 3-level diode-clamped converters

Summary form only given. This paper offers a novel topology for the implementation of a shunt STATCOM based on a grouping of four 3-level, diode-clamped converters, switching at line frequency and coupled to the AC system through wye/wye and wye/delta phase-shifting transformers. Advantages include direct voltage control through the gating pattern and reduced size of DC capacitor. The dominant harmonic on the AC side is the 11/sup th/ and on the DC side the 12/sup th/. The proposed STATCOM can meet typical harmonic distortion requirements.