Research on Lighting IMPULSE BREAKDOWN CHARACTERISTIC OF c-C_4F_8 AND N_2 GAS MIXTURE IN ROD-PLANE GAPS

摘要

Researches on new alternative gases for SF_6 as dielectric medium have become more and more urge since SF_6 gas was specified as a greenhouse gas at COP3 in 1997. Optimum gaseous dielectric in terms dielectric strength are mixtures of the strongly electronegative gases with abundant, inert, and inexpensive buffer gas. Among all electronegative gases with high dielectric strength, c-C_4F_8 gas has not only much lower GWP than SF_6, 36% of SF_6, but also no toxic and ozone depletion potential entirely.Generally speaking, the insulation dimensions of gas-insulated systems are determined by the lightning impulse withstanding voltages. This paper investigated experimentally the lighting impulse breakdown characteristics of rod-plane gaps in c-C_4F_8+N_2 for different gap spacing, gas pressure and c-C_4F_8 gas content.