Modelled, Simulation and Design of Collecting Grid of Stray Currents in Slab Track in DC Electrified Railway Systems

摘要

The stray currents are the fraction of traction return current returning by earth in at grade configurations, or by metallic structures (reinforcement bars) in case of viaducts and tunnels. These currents expose steel reinforcement bars to corrosion. The obvious alternative to minimize the risk of corrosion is to minimize the stray current, using insulation sleeper insulating pads and insulated bolts in fastener blocks. However, due to mechanic wearing by train operation, aging, or accumulation of waste, the level of insulation between rail and structures decreases with time, which increases the stray currents. A common palliative method for this is to install a Stray Current Collector (SCC), a conductive grid or mat, embedded in the concrete structure below the rails. The SCC can be connected to earth and to return circuit in different ways. The objectives of the paper are to get a model of leakage resistances including the SCC system, to determine the effectiveness of SCC and the best connection scheme.