Study on electrical endurance for capacitive current switching of 1100kV circuit breakers used for filter banks

摘要

Receiving ends of ±800 kV and ±1100 kV UHVDC project constructed by State Grid Corporation of China are hierarchically connected to 500 kV and 1000 kV AC power grid. In these projects, 1100kV column circuit breakers, also called live tank circuit breakers, with composite insulators and four break units in series are used in 1000kV AC filter banks. Considering wider range and more frequent adjustment of power in Ultra-high voltage grid, filter banks will be switched more frequently. It is expected to about 500 times per year, and the recovery voltage is up to 2900kV in extreme operating conditions. So the requirement on capacitive current switching performance is very strict.