Innovation of Switching Technologies in Power Systems

Switching technologies applied to future power systems are facing with new requirements under changing network conditions. The roles of switching equipment used in AC and DC power systems may be also changing due to emerging factors such as massive installation of intermittent distributed renewable sources as well as energy storages. Rapid fault clearing HVDC circuit breakers are required to realize the future meshed HVDC grids. Despite of excellent arc interruption capability, since SF6 is a strong greenhouse gas with a high global warming potential (GWP) of about 23500, electric power industries continuously have enforced to reduce its release and leakage from t switching equipment. Considerable efforts have been focused to find an alternative solution with less environmental impact but there is still no practical and economic applications of SF6 free switching equipment applicable to EHV and UHV transmission systems, while increasing applications of vacuum interrupters up to 145 kV levels. In the paper, Technical trends and forecasts of AC and DC switching technologies applicable to future power systems will be presented.