Grounding Points Model for Safety Enhancement in Autotransformer Configuration Railway System

Electrified Urban Massive Transportation Railway Systems require the supply of electric power that complies to electromagnetic and safety standards, as well as operational regulation.  This paper presents a mathematical modelling of a complete Autotransformer Configuration Railway System. The innovation of this study relies on the consideration of grounding points to calculate realistic rail voltages to perform safety improvements. This research incorporates the Carson’s Line model to accurately depict the self- and mutual- impedances between the conductors of the railway system. A case study is simulated using real-world rail data from a quad-track AT railway system located in United Kingdom. The results have proven that the inclusion of grounding points in the load model significantly reduces the rail voltage resulting from self- and mutual- induction, thus increasing the effectiveness and robustness in achieving more realistic voltage calculations and enhancing safety level for improved industry practices.