Electrical performance of 330-kV composite insulators under icing conditions

Composite insulators have been widely used in high voltage transmission lines more than 20 years in China due to their hydrophobic properties, relatively low weight and maintenance costs, and high mechanical strength. Shed configuration is a key factor that influences flashover voltage of composite insulators under icing conditions. In order to study the effect of shed configuration on the flashover performance of composite insulators under icing conditions, the electrical performance of five types of 330-kV composite insulators with different shed designs were compared under artificial icing conditions. Experiments were carried out in the multi-function climate chamber in Chongqing University. In order to explain the influence of shed configuration, electric field and potential distributions along each insulator type were calculated numerically using the finite element method (FEM). The numerical simulation results were found to be in agreement with the laboratory experimental ones.