Arc endurance modeling of polymeric HV outdoor insulating materials

Arc induced degradation of polymeric materials used for outdoor HV insulation has been studied using a 532 nm visible wavelength laser. The degradation behavior is modeled by a modified Helmholtz equation. Two parameters are introduced in the theoretical model developed; a propagation factor α which is predominantly dependent on the laser power, and an ablation factor β , which is a function of material properties. The performance of housing materials used for outdoor line and apparatus insulators such as, silicone rubber, ethylene propylene diene monomer (EPDM) rubber and cycloaliphatic epoxy has been evaluated and modeled.