Evaluation of the Damage Caused by Bird Pecking Activity along Composite High Voltage Insulators

Bird pecking is one of the causes for deterioration of composite insulators. It concerns the removal of parts of the polymeric housing due to the attack by large birds. Such damages on the insulator housing rise questions concerning the efficiency and reliability of the bird-pecked insulators. This study evaluates the damages due to bird pecking activity detected on the housing of two 150 kV liquid silicone rubber tension insulators. Both insulators were operated for 15 years without experiencing faults in an overhead transmission line of Crete crossing an area highly populated by the griffon vulture. The impact of the deformed sheds on the electric field distribution along the housing surface is assessed through electrostatic simulations. The surface electric field is locally enhanced; this is of great concern when damages due to bird-pecking activity are detected along the high electric field areas of the insulator.