Determination of maximum span length of utility lines based on consideration of eliminating magnetically induced subsequent fault

Abstract

As an electric fault occurs, a strong magnetic force exerted on three-phase overhead power lines may bring them in close proximity or in contact with one another, causing a subsequent fault. A computer simulation has been developed for the analysis of the magnetically induced subsequent fault and presented in the authors’ earlier work. It has been found that one important factor affecting the probability of the subsequent fault is the power line configurations. In this paper, we present a numerical technique for determining the maximum span length of the power lines based on consideration of eliminating the magnetically induced subsequent fault. Various power line constructions corresponding to different fault current levels are investigated. The results presented in this paper are anticipated to be useful for a utility in long span design.