Creeping flashover characteristics in (N ₂ /SF ₆ ) gas mixture under pulse voltage

Abstract

The effect of a barrier between a needle electrode and a plane one in an (N2/SF6) gas mixture on creeping flashover was investigated using a microsecond pulse voltage. The SF6 gas content was varied from 0% to 100%, and the gas pressure from 0.1 MPa to 0.3 MPa. The flashover voltage increased with increasing SF6 gas content for a positive needle electrode. For a negative needle electrode, excepting the total pressure of 0.1 MPa, at which similar flashover characteristics were obtained to the positive case, a considerable decrease in flashover voltage was found in the case of a mixture of a few percent SF6 in (N2/SF6) gas mixture at elevated total pressures. The corona behavior on the barrier in (N2/SF6) gas mixture was investigated by means of a high‐speed digital framing camera. © 2000 Scripta Technica, Electr Eng Jpn, 131(1): 1–9, 2000