Dynamism of Parasite Capacitance of AC Electric Traction Line Inside the Railway Tunnels

Abstract

Air pollution by the fossil fuel-driven vehicles in the urban and suburban sections in the developed countries forced the adoption of electric traction in railways. Subsequently, traffic dense rail routes in many developing countries were also switched over to high voltage electric traction to reduce their dependency on petroleum products. Developing countries are the main beneficiaries of the high voltage electric railway traction system. As a result of the operational constraints evolved in maintaining partially electrified rail routes, developing countries are trending to electrify more rail routes at geographically challenged areas also. Tunnels constructed for metro railways in urban sections also raise the similar geographical challenges. Power supply interruption happened due to persisting earth fault on electric traction system even for a short duration will paralyze the rail network to a large extent. Hence precisely pin pointing the fault distance is essential to ensure the railway system reliability. Undesirable variations occurred in line parameters due to the bare conductors for the electric traction inside railway and metro train tunnels for very long stretches due to proximity of earth potential, and the subsequent nuisance crept in line fault distance locating algorithm studied through the experimentations conducted in actual working condition for re-modelling high voltage ac electric railway traction to precisely pin pointing the fault distance of it are presented in this paper.