High-voltage oil circuit breakers for rapid reclosing duty

Experience has shown that high-speed reclosing of circuit breakers on high-voltage transmission lines is of considerable value in maintaining system stability and continuity of service. This paper describes a new line of outdoor oil circuit breakers and the special design features which make them suitable for 20- and 35-cycle reclosing duty at voltages as high as 230 kv. Data are included showing high-power-laboratery short-circuit tests on these duty cycles at 138 kv and 230 kv at currents corresponding to three-phase duty of more than 2,500,000 kva.