Influence of modelling assumptions in rigid catenary systems on pantograph-catenary interaction

The pantograph-catenary interaction governs the electrical current collection quality in railway systems and is strongly influenced by the geometrical configuration of the overhead line. While the importance of pre-sag and staggering has been extensively studied for flexible catenary systems, their relevance in rigid catenary configurations remains unclear. This work numerically investigates the influence of pre-sag and staggering on the dynamic interaction between pantograph and rigid catenary. To do so, a numerical framework has been developed using two pantograph representations: a conventional lumped-mass model compliant with EN 50318 and an extended model including lateral and rotational degrees of freedom of the pantograph head. In the latter, the contact strip is modelled as a flexible beam, enabling the representation of laterally distributed contact forces and stagger-induced effects. Parametric analyses are performed to quantify the impact of geometric variations on contact force response. Results show that pre-sag produces moderate changes in contact force statistics for rigid catenary systems at low speed operation. In contrast, staggering introduces significant variations when lateral dynamics are considered, affecting both the amplitude and distribution of contact forces along the strip. The results demonstrate that simplified vertical pantograph models are insufficient to capture staggering-induced effects when simulating pantograph-catenary contact force for in rigid catenary systems.