Simulation of EHV Transmission Line Flashovers Initiated by, Bird Excretion

During the past two years, unexplained flashovers have caused 32 outages on the Bonneville Power Administration 500 kV ac transmission lines. Tests reported in this paper indicate that some of these unexplained flashovers may have been caused by large birds and leave little or no evidence of the cause. It is also shown that this mechanism may cause flashovers on ehv dc transmission lines.