ASSESSMENT OF BASIC CONTAMINATION WITHSTAND VOLTAGE CHARACTERISTICS OF POLYMER INSULATORS

An artificial contamination method for hydrophobic polymer insulators was newly developed, which can provide a uniform contaminant layer sim ilar to the natural one neither by damaging the polymer surface nor by adding any chemical agent to the conventional contamination slurry. U sing this method, basic contamination withstand voltage characteristic s of polymer insulators were investigated comparing with those of porc elain insulators. The results show that although hydrophobic polymer i nsulators generally have excellent contamination withstand voltage cha racteristics critical reduction of withstand voltage occurs sometimes under rapid and heavy wetting and contamination conditions.