ROLE OF NON-SOLUBLE CONTAMINANTS ON THE FLASHOVER VOLTAGE OF PORCELAIN INSULATORS

The influence of non-soluble or inert contaminants on the flashover vo ltage of HV outdoor porcelain insulators is examined. A dynamic are mo del, presented earlier for predicting the flashover voltage of porcela in insulators covered with water soluble contaminants, has been modifi ed suitably. The extended model has been used to predict the flashover voltage of suspension and station post insulators of various shapes f or both ac and de voltages. Good correlation with experimental data ha s been shown. The model can thus be used as a computer aided tool for design and maintenance of HV porcelain insulators.