Determination of Electromagnetic Noise from a Power Supply Substation of Railway Traction Systems

Abstract

This paper aims at determining with methods to determine the electromagnetic noise that occurs when supplying electric trains from substations. The supply voltage from the substation and the current absorbed through the supply line by an electric train are analyzed. Aspects of electromagnetic interference and the occurrence of electromagnetic noise in railway traction systems are discussed. The specialized standards that address the issue of noise and the implications of the electromagnetic interference in the railway electrical network are briefly presented. The evaluation of the electromagnetic noise by mediation at quasistationary signals is presented. The algorithm for determining the average signals when there are deviations from stationarity is presented. The way to determine the electromagnetic noise for a transformer station that supplies the power line from which the trains are powered is discussed. Measured data of the situation of determining the electromagnetic noise from the supply voltage of the line and from the current absorbed by a train moving in the vicinity of the transformer station is provided as an example. The influences of the electromagnetic noises of the line voltage and the train current over the common and differential currents in the substation, affecting the electrical equipment located on the electric train, are highlighted.