Development and testing of prototype models for a high-performance 300 MW self-commutated AC/DC converter

A technical project is under way in Japan to develop a high-performance self-commutated power converter for future HVDC transmission and DC interconnection applications. In the first stage of the project, prototype power converter models for a 300 MW self-commutated converter were developed. The models were subjected to factory testing to verify the technology for series connection of a large number of gate turn-off thyristors (GTOs), a gate power supply from the high voltage main circuit and energy regeneration using snubber circuits. Satisfactory results were obtained.