Comprehensive Simulation Of AT Traction Power Supply And Integrated Grounding System

In recent years, the strong development of China’s electrified railway, especially had been applied in high-speed and heavy haul railway. However, the traction current and traction power of high-speed and heavy rail were larger than the existing lines, then rail potential and traction return were much increased. After the introduction of integrated grounding system, traction return distribution and quantitative analysis of electromagnetic interference on signal system had not been systematically studied. Against this background, this paper researches traction return current distribution and strong conductivity electromagnetic interference on track circuit and signal cables for Datong-Qinhuangdao heavy haul railway, major work focuses the following four aspects.At first, according to wire configurations and structure settings of Datong-Qinhuangdao Railway Traction Power Supply System, its specific impedance parameters were solved by existing impedance theoretical calculations, providing basic data support for subsequent simulation.Secondly, continuous mathematical model of rail current and potential under single-line AT power supply was deduced, the accuracy of system node model was verified and the applicability of both were analyzed. The factors that affecting rail potential were simulated and the impact of ground parameters on rail current and potential were detailed analyzed.Thirdly, node model of Datong-Qinhuangdao full parallel double-track line was established, current and potential of rail, protective wire, ground and conductive current of signal cables under double-grounded were determined in case of no bridge sections, bridge sections and ground disconnection, current distribution ratio was obtained and the theoretical simulation accuracy was verified combined with field testing.Finally, track circuit detour caused by electrical system cross-linking was analyzed, electromagnetic interference on cable core was calculated, it provided reliable data for the evaluation of signal cable grounding. The conclusion was that interference effect was not significant while signal cable double-grounded compared with single-grounded.