Improved Shape-Finding Modeling and Dynamic Performance Analysis of Electrified Railway Pantograph–Catenary Coupling System in Noncrossing Turnout Section

Noncrossing catenary turnout section is a specific catenary arrangement for electrified railways. The height of the contact wire changes dynamically to enable the pantograph to transition between catenaries. The change in the height of the contact wire not only creates a height difference between the two endpoints of the contact wire but also leads to uneven tension distribution along the contact wire and changes in its sag, all of which are factors that can affect the equal-height point. In view of these issues of the contact wire, this article improves the catenary shape-finding model for the noncrossing turnout section based on the parabolic-shaped cable element and the catenary-shaped cable element, conduct shape-finding for the cable elements at different positions. The improved catenary shape-finding model is derived in detail, including the calculation of the unbalanced force of cable elements, the cable element shape-finding improvement, and the dynamic modeling of the catenary. A pantograph–catenary coupling model is established based on the improved catenary model. Using data from the No. 18 turnout on the Yinchuan–Lanzhou passenger dedicated line in China, the improved shape-finding model and the pantograph–catenary coupling model are validated, which shows that the deviation of the improved model is less than 5% and complies with EN50318. The influence of the parameters of the noncrossing catenary turnout on the pantograph–catenary coupling is analyzed using the improved model. The results show that the equal-height point is the primary influencing factor.