Fanyi Cai / NARI Group Corporation (State Grid Electric Power Research Institute)
Jian Xue / NARI Group Corporation (State Grid Electric Power Research Institute)
Baijie Zhou / NARI Group Corporation (State Grid Electric Power Research Institute)
CF3I has been recognized as an attractive insulating medium for substituting SF6 gas in high-voltage switchgear insulations, because it has low global warming potential (GWP) and an insulation capability that is 1.2 times greater than that of SF6. In this paper, the AC breakdown tests on CF3I/N2 gas mixture have been completed in a sphere-plate geometry. We reveal the effect laws of mixture content, gas pressures, and gap distances. The results indicate that the insulation strength of the CF3I/N2 gas mixture will be efficiently improved by prolonged insulation distance and higher gas pressure. And the insulation ability of the CF3I/N2 gas mixture were demonstrated in a 12kV C-GIS designed for SF6 gas when the gas is replaced with Alternative Gas.