Arc Interruption Performance of SF6/N2 Gas and Dielectric Recovery in Disconnector

SF6 as a gas medium for power switchgear, has outstanding performance on arc suppression and insulation. However, because of the strong greenhouse effect, it is limited to use recently. SF6/N2 mixture is an effective alternative in high voltage power switchgear, which not only reduce the emission of SF6 but also lower the gas liquefaction temperature. Based on a 220 kV disconnector, this paper built a magneto-hydro-dynamic (MHD) model to simulate the arc burning process. The electric field distribution and the critical breakdown voltage within 100 us after current zero (CZ) were calculated to evaluate the arc interruption performance of the SF6/N2 mixture. The model established in this paper is effective and referable in arc simulation and dielectric recovery assessment. The research results in this thesis are significant to the application of SF6/N2 mixture in disconnectors.