Yiming Dong

The electrical arcs generated by high-speed dynamic separation between pantograph and catenary systems pose a significant threat to the operational safety of high-speed railways. Environmental factors, particularly relative humidity and airflow, critically influence arc characteristics. This study establishes a two-dimensional pantograph–catenary arc model based on magnetohydrodynamic theory, validated through a self-developed experimental platform. Research findings demonstrate that as relative humidity increases from 25% to 100%, the core arc temperature decreases from 10,500 K to 9000 K due to enhanced heat dissipation in humid air and electron capture by water molecules; the peak arc voltage rises from 37.25 V to 48.17 V resulting from accelerated deionization processes under high humidity conditions; the average arc energy in polar regions increases from 2.5 × 10⁻⁴ J/m³ to 3.5 × 10⁻⁴ J/m³, exhibiting a saddle-shaped distribution; and the maximum arc pressure declines from 5.3 Pa to 3.7 Pa. Under airflow conditions of 10–30 m/s, synergistic effects between airflow and humidity further modify arc behavior. The most pronounced temperature fluctuations and most frequent arc root migration occur at 100% humidity with 30 m/s airflow, while the shortest travel distance and longest persistence are observed at 25% humidity with 10 m/s airflow, as airflow accelerates heat dissipation and promotes arc root alternation. Experimental measurements of arc radiation intensity and temperature distribution show excellent agreement with simulation results, verifying the model’s reliability. This study quantitatively elucidates the influence patterns of humidity and airflow on arc characteristics, providing a theoretical foundation for enhancing pantograph–catenary system reliability.

During train operations, the contact surface between the pantograph slide and the catenary wire is subjected to mechanical friction and an electrical current, leading to an increase in the wear of the pantograph slide and a reduction in the service life of the pantograph–catenary friction pair. Therefore, the study of pantograph slide wear modeling and prediction is of great significance. This paper proposes a method to quantitatively characterize the wear of the pantograph slide by analyzing the energy dissipated through current-carrying friction in the pantograph–catenary system, from the perspective of the work done by the system. This study finds a significant linear relationship between the wear of the pantograph slide and the energy dissipated by current-carrying friction and establishes a mathematical model for pantograph slide wear based on energy dissipation, validating the effectiveness of the model. Furthermore, the relationship between the dissipated energy, contact current, contact pressure, and sliding speed is explored using experimental data, providing a quantitative explanation of the interaction between electrical and mechanical wear from an energy perspective. The wear morphology of the pantograph slide surface is further examined using metallographic microscopy, and the wear mechanism is analyzed. The applicability of the wear model is discussed, and it can be used for further studies on the current-carrying wear mechanisms in pantograph–catenary systems.