Volt-Time Characteristics of Short Rod-Rod Gaps PDF

Keywords

volt-time, air gaps, gap spacing, impulse polarity

Abstract

In this paper volt-time or V-t characteristics for rod-rod air gaps are determined experimentally using positive and negative standard lightning impulses for gap spacings in the range of 5 to 25 cm. The rods were of cylindrical shape with hemispherical ends and had tip radii in the range of 1 to 5 mm. From the measurements, the effect of rod tip radius, gap spacing and impulse polarity on V-t characteristics is examined and empirical equations for predicting the V-t characteristics of short sir gaps are proposed. The values of breakdown voltage predicted by the proposed equations are compared with measurements reported in the literature and a good agreement is observed between the two sets.