Reducing electromagnetic pollution of the environment at main railway facilities

Abstract

PurposeThis paper aims to explore the effectiveness of special transformers (STs), integrated into the section of the catenary system and additional return wire, in reducing electromagnetic pollution at mainline railway facilities.Design/methodology/approachThe formulated objective is accomplished through the developed computer models of the traction power system of the main AC railway with a voltage of 25 kV in the catenary system. The traction power system was equipped with special transformers and additional return wires to enhance the shielding effect of the track in order to reduce the electromagnetic field (EMF) strengths that negatively affect personnel, the population and the environment. Multivariate modeling is conducted to determine the performance of special transformers. For comparison, the electromagnetic field of a typical traction power system is calculated without using special transformers. Modeling is conducted using the Fazonord software product developed at Irkutsk State Transport University. This software facilitates the calculation of operating parameters of traction power system and the assessment of the EMF of special transformers of various designs.FindingsThe findings reveal that special transformers of a relatively low power of 225 kVA, when integrated into the section of the catenary system and an additional return wire, significantly improve the conditions of electromagnetic environment. This method does not require considerable capital outlays and can be implemented on existing and planned sections of electrified railways. Computer modeling within this approach enables a reduction in the average values of strength at a height of 1.8 m by 16% – for the electric field and by 62% – for the magnetic field. Similar indicators for a height of 0.5 m are 17% and 65%, respectively. The physical mechanism of minimizing the EMF strength lies in increasing the shielding effect of the track.Originality/valueThe approach applied to address the electromagnetic environment issues is original and differs from known ones in the following aspects: systemic nature, involving the possibility of calculating EMF, given the properties and characteristics of a complex traction power system and feeding power system; versatility, ensuring the modeling of traction networks of various designs; adequacy to the external environment, achieved by considering the profile of the underlying surface, underground communications, artificial structures of railway transport, such as galleries, bridges and tunnels; comprehensive nature, provided by combined calculations of the power flow and the determination of EMF strengths.