Estimation of leakage current of arc discharge on insulating material surface using area of luminance caused by arc discharge on ultraviolet images

An estimation method for leakage current on an insulating material surface using the area of luminescence arising from discharge on an ultraviolet image has been developed. When the discharge occurs, the area of luminance is the region of luminance arising from the discharge. Our assumption is that the area of luminance caused by the discharge correlates to leakage current on the surface. To confirm our assumption, the relationship between the area of luminance and leakage current was investigated. Four insulating materials (e.g., silicon rubbers and porcelain) were used. In all the cases, the area of luminance correlated to leakage current. The results indicate that the area of luminescence caused by discharge could be used to estimate leakage current.