Abstract: Water is mixed with soluble conductive material in haze so that the air has certain conductivity, resulting in extra mixed pollution components on the surface of the existing polluted insulator. In this paper, with the XP10-160 ceramic suspension insulator being used as the sample, the switching impulse test of the clean and polluted insulator is carried out by simulating high conductivity fog under the natural environment by salt fog method. This paper analysis the flashover characteristics of switching impulse under different salt density and water fog conductivity. The effect of high conductivity fog on the field intensity distribution of insulator is simulated and analyzed. This paper collects the waveform of switching impulse flashover in different fog conductivity, and the wave head and wave tail time are shorter than the standard waveform, which also confirms the non-standard switching impulse wave that mentioned in the relevant literature.

Key words: porcelain insulator, high conductivity fog, switching impulse, salt density, wave form