Arc Behavior in Rotary-arc Type of Load-break Switch and its Current-interrupting Capability for Different Environmentally Benign Gases and Electrode Materials

Abstract

In the purpose to find an alternative gas to SF6, this paper describes the results of current-interruption experiment for a rotary-arc type of load-break switch filled with CO2, H2, He and SF6 at an absolute pressure of 0.1MPa in case of ring electrode made of stainless steel. In addition, in case of the switch filled with CO2, current-interruption experiments were also performed for the ring electrode made of copper. The interrupting capability was found to be higher in order of SF6, H2, CO2 and He. Moreover, the switch proved to have the higher current-interrupting capability for the copper than for the stainless steel. The phenomenon was found to arise from change in magnetic flux in an inner space of a ring electrode, depending the electrode material. This change in the magnetic flux also proved to result from variation of a resistance of the ring electrode.