Frequency of distribution arrester discharge currents due to direct strokes

Abstract

The "Electrogeometric" Theory, developed for transmission line lightning performance calculations, is applied to distribution systems as a means of predicting arrester discharge currents. The resulting rates of occurrence and frequency distributions compare favorably with presently available information. The effect of stroke location on attester current is explained and shown to be significant. Predischarge and pole reflections are shown to have similar effects, and do not significantly affect crest current. Footing resistance is accounted for. Indirect strokes are treated briefly and shown to produce minimal arrester current.