Computer-aided Design of Porcelain Insulators under Polluted Conditions

The development of a user-friendly, interactive personal computer package for designing insulators to be used in polluted conditions is presented. This is accomplished by integrating a dynamic arc model that computes the pollution flashover voltage within the Microsoft Windows application program. Suspension, station post and pin type insulators of numerous shapes have been incorporated into the package. The model is capable of handling ac and dc voltages, in addition to uniform and nonuniform pollution distributions on the insulator surface. The use of the model as a design tool to predict the insulation requirement for a given system voltage, and as a maintenance tool to determine the critical contamination level (in terms of ESDD) that will cause flashover of the insulator at the operating voltage, has been demonstrated. Wherever possible, comparisons of the model predictions with experimental data have been made, and good agreement has been obtained.