Contamination Flashover, Part I: Theoretical Aspects

This paper discusses some of the physical processes involved in the flashover of insulators with contaminated surfaces. Past theories of discharge propagation across moist films are reviewed and found to be unsatisfactory in certain respects. To better account for what is observed, it is proposed that under certain conditions contamination flashover is an electrical breakdown process, rather than a drying process or an electrical instability as has been generallly assumed.