Breakdown Mechanisms in Sulphur-Hexafluoride

The well known breakdown theories, Townsend´s generation mechanism and the streamer mechanism, are reviewed and applied to the results of breakdown in the strongly electronegative gas, sulphur-hexafluoride. Experimental results reported in the literature on the breakdown behavior of sulphur-hexafluoride are examined in the light of these theories. The breakdown theories are used for the estimation of the breakdown voltages in pure SF6. Other factors that may affect the breakdown characteristics of SF6 have been discussed. Further areas of work have been proposed in order to obtain a better understanding of the breakdown mechanism.