Flashover of composite insulators induced by bird excretion

This paper simulates a.c. 110 kV and 220 kV composite insulator flashover induced by bird excretion. It finds that contaminated wet composite insulators are more likely to suffer from bird excretion flashovers than dry clean ones. Wet contaminated composite insulator flashover induced by bird excretion is the combination of arcing along the insulator surface and the breakdown along the dry arc distance. Meanwhile, dry clean composite insulator flashover induced by bird excretion is usually only the result of air breakdown along the dry arc distance. The maximum value of the distance between the bird excretion falling passage and contaminated wet insulator shed to induce flashovers is higher than that of a dry clean one. Some of the unexplained flashovers may actually be induced by bird excretion.