Electromagnetic Interferences between diverse Traction Electric System

The International Union of Railways (UIC) presents IRS-70794:2025, Edition 1, a technical document addressing electromagnetic interferences (EMI) between diverse traction electrification systems. This IRS provides a comprehensive analysis of EMI effects, focusing on the interactions between alternating current (AC) and direct current (DC) railway networks. The document is structured to facilitate the identification, modelling, and mitigation of electromagnetic disturbances, ensuring compatibility and operational safety across railway infrastructures.

Issue: This IRS sets out to examine and address the electromagnetic compatibility challenges posed by the coexistence of different railway electrification systems. The increasing complexity of railway networks, particularly where AC and DC traction systems operate in close proximity, necessitates a thorough understanding of electromagnetic interferences and their potential impact on safety, infrastructure integrity, and operational efficiency.

It primarily addresses the technical challenges associated with EMI in railway electrification, particularly those arising from AC and DC systems operating in parallel or crossing configurations. The document serves as a critical reference for infrastructure managers, railway operators, and technical specialists involved in the planning, design, maintenance, and operation of electrified railway lines. By providing validated methodologies for identifying and mitigating EMI, it aims to enhance interoperability and reliability within railway networks.

It contains a detailed study of electromagnetic disturbances, incorporating empirical data from extensive field testing and advanced computational modelling. The methodologies applied include preliminary consultations with UIC members, real-world measurements conducted on high-speed and conventional railway lines, and the development of predictive simulation models using COMSOL Multiphysics and MATLAB. The MATLAB-based application, developed as part of the study, provides an accessible and user-friendly tool for evaluating induced voltages and magnetic field disturbances in railway environments. By allowing users to define variables such as catenary geometry, substation locations, grounding configurations, and rolling stock characteristics, the MATLAB model enables in-depth scenario analysis, facilitating EMI impact assessments under various operational conditions. Key findings include the identification of significant 50 Hz perturbations in DC traction substations, the impact of EMI on track circuits, and the critical role of parallel and crossing line configurations in amplifying induction effects. The document also présents possibilities for infrastructure design improvements, mitigation strategies such as optimised grounding techniques, and the importance of regulatory alignment to ensure consistent EMI management across different railway networks.