Harmonic characteristic analysis of Capacitor Commutated Converter in HVDC system

Capacitor Commutated Converter (CCC) is a new kind of converter characterized by having capacitors inserted in between the converter transformer and the converter valves. Its behavior as harmonic source is the research point of this paper. Characteristic harmonics at the dc and ac side of CCC-HVDC system are studied, analyzed and compared with the Line Commutated Converter HVDC (LCC-HVDC) system. Thus it can analyze the influence of series capacitor at the dc and ac side characteristic harmonics of the converter. The research is based on the Qing-Zang HVDC transmission project (a planning project), and consists of two parts: theoretical calculations and simulation analysis. The simulation tool is PSCAD/EMTDC.