DC Fault Clearing Characteristics of a Bulk Power VSC HVDC Transmission System using DC Circuit Breakers

Development of wind power generation resources is considered in Japan. However, long‐distance transmission lines are necessary to utilize the wind power because most of the wind power resources are distant from load centers. A voltage source converter based high voltage dc transmission (VSC HVDC) system is an option to realize their effective use. A VSC HVDC system equipped with dc circuit breakers has been considered to clear the dc line faults promptly. However, the fault clearing characteristics by the dc circuit breakers have not been analyzed very well for the system with the long distance overhead transmission line. This paper focuses on a fault clearing in the VSC HVDC system with long‐distance overhead line by the dc circuit breaker using a new fault detection method. A 2.4‐GW bipolar VSC HVDC system with 600‐km overhead transmission line is modeled and its operation performance is verified by computer simulations. The simulation results demonstrate the detailed fault clearing characteristics with the long transmission line. Moreover, specifications required for the dc circuit breakers are considered in terms of operation delay, peak current, and absorbed energy.