High voltage diagnostic measurements for surge arrester condition monitoring

The electric grid is protected from lightning damage by surge arresters. Surge arresters are sacrificial elements that must be replaced to maintain lighting protection once they are damaged. In a survey of the U.S., it has been found that the highest population of damaged surge arresters is in the region of highest lightning density. Samples of surge arresters that have been identified as damaged have been evaluated in a high voltage laboratory using electromagnetic interference, partial discharge, and ultrasonic emission detection technology. The results of this evaluation are presented along with opportunities for further study.