Method of diagnosing the deterioration of a zinc oxide type lightning arrester utilizing vector synthesis

摘要

A method of diagnosing the deterioration of a zinc oxide type lighting arrester having one or more series-connected non-linear resistance elements including steps of elimination of the effects of capacitive currents from phase currents; obtaining a synthesized waveform using a window type transformer based on the resistance elements alone; and diagnosing the presence of a deteriorated non-linear resistance element by generating a first pulse voltage when the maximum crest value of the synthesized waveforms exceeds a predetermined value, generating a second pulse voltage representative of terminal voltage of the resistance element, and calculating the difference between the first and second pulse voltages.