Model development for determining the potential difference between rail and ground on electrified AC railways sections

Introduction. The active use of geosynthetic materials in the modernisation of railway track in order to enhance its mechanical stability leads to a significant increase in the electrical ballast layer resistance. This presents challenge for electri- fied AC railways, as it disrupts the normal flow of reverse traction currents and leads to dangerous potential differences between the rail and the ground. The aim of the study is to develop and verify a physical-mathematical model for the as- sessment of potential difference between the rail and the ground on electrified AC railways sections for a quantitative assessment of rail potential and analysis of the effect of the ballast prism structure on its distribution.

Materials and methods. In order to solve the problem, the authors developed a refined physical-mathematical model based on the finite element method, which allows to consider the spatial heterogeneity of the electrical parameters of the pipe. The model integrates the resistance of various structural elements of the track: rails, sleepers, ballast and roadbed. Field experiments were conducted on the Experimental Loop of the Railway Research Institute to validate the model.

Results. Experimental studies confirmed the adequacy of the developed model. The calculation results demonstrated a high degree of consistency with the field measurements data of the potential distribution along the way. As a result of the work carried out, a tool has been created for solving applied problems related to determining the potential difference between the rail and the ground.

Discussion and conclusion. Comparison of the experimental and calculated data of the refined physical-mathematical model shows that the developed model is presented as an effective tool for predicting potentially dangerous sections at the ballastless track superstructure design.

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