Modeling the magnetic field emissions from a third rail system

Magnetic field emissions extending from low frequency to several MHz are the main electromagnetic phenomenon that characterize the emissions of electrified traction lines. In this paper a general model is proposed based on Biot-Savart law as a low frequency approximation and Hertzian dipole equations for the extension to the high frequency range. The current in the line conductors are computed with a Multiconductor Transmission Line simulator. The results are compared with the data collected in a measurement campaign operated on a metro line equipped with third rail system.