Quantification of Damage due to Surface Tracking

Fractals have been very successfully used to address the problem of modeling and to provide a description of naturally occurring phenomena and shapes, wherein conventional and existing mathematical models were found to be inadequate. The geometrical patterns of dielectric breakdown like electrical trees, surface discharges, and lightning are known to be of fractal in nature. These fractal patterns can be analyzed numerically using fractal dimensions and lacunarity. Surface tracking occurring in HV insulation systems is a very complex phenomenon and more so are the shapes of tracking patterns. It has been fairly well established that the shapes and the underlying parameters causing tracking have a 1:1 correspondence and therefore methods to describe and quantify these patterns must be explored. This contribution reports preliminary results of such a study wherein 2D tracking patterns of gamma irradiated ethylene propylene diene monomer (EPDM) were analyzed and found to posses' fairly reasonable pattern discriminating abilities.