Lightning Transients of the Overhead Catenary System Pillar and its Adjacent Grounding Systems in a High-Speed Railway Depot

Abstract

We have surveyed a signaling equipment failure caused by the spread of ground potential rise (GPR) between the overhead catenary system (OCS) pillar with two anchor cables and the trackside equipment due to lightning strikes to the pillar in a high-speed railway depot. Also, we evaluate the lightning currents on these conductors and their GPR considering the effect of soil conductivity <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">σ</i> and distance <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</i> between the trackside equipment grounding rod and the anchor cable grounding system by using the 3-D finite-difference time-domain method. The simulation results show that the lightning current on the OCS pillar is shunted by anchor cables, and the distribution of currents on these conductors is influenced by soil conductivity. With the increase of soil conductivity, the current on the pillar increases, and the current on the anchor cable decreases. The GPR of the grounding systems is affected by the soil conductivity, and the GPR increases with the decrease of soil conductivity. Moreover, the GPR of trackside equipment grounding rod decreases with the increase of distance <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</i> .