An approach to geometric optimisation of railway catenaries

Abstract

The quality of current collection becomes a limiting factor when the aim is to increase the speed of the present railway systems. In this work an attempt is made to improve current collection quality optimising catenary geometry by means of a Genetic Algorithm. As dropper lengths and dropper spacing are thought to be highly influential parameters they were chosen as the optimisation variables. The results obtained show that a Genetic Algorithm can be used to optimise catenary geometry to improve current collection quality measured in terms of the standard deviation of the contact force. Furthermore, it is highlighted that apart from the usual pre-sag, other geometric parameters should also be taken into account when designing railway catenaries.

Stochastic Monte Carlo simulations of the pantograph–catenary dynamic interaction to allow for uncertainties introduced during catenary installation

“…A certain amount of pre-sag is beneficial for current collection quality, especially in the medium speed range [30]. Optimal pre-sag values for a given train velocity are reported in [3], but only for deterministic simulations that ignored the variability of installation errors. Here we obtained a robust optimal pre-sag value, allowing for the uncertainty present in the installed catenaries.…”

“…The simulation of the pantograph-catenary dynamic interaction has become an important tool for catenary designers in recent years (see [1] and the references therein). Simulations are helpful when different geometries, configurations and materials need to be tested or even optimized [2,3], with no need for a prototype or expensive in-line tests. However, these simulations usually provide deterministic results, such as optimized geometries or sensitivity studies [4], in which magnitudes like the interaction force or the uplift at a certain point of the catenary do not allow for the variability present in the system.…”

A new methodology to study the pantograph–catenary dynamics in curved railway tracks

“…The development of specialized numerical applications for the dynamic analysis of pantograph-catenary interaction plays a significant role in the analysis and design of railway network assets. An extensive amount of publications on the development and application of computational methods and applications in pantograph-interaction can be found in the literature, addressing analysis of multiple pantograph operation [6][7][8], analysis of critical catenary sections [9][10][11], and optimisation of pantograph and catenary designs [12][13][14] among other issues of importance. The perturbation of the quality of contact in the pantograph-catenary interface due to aerodynamics effects, vehicle vibration and catenary irregularities [15][16][17][18][19] are also considered in the literature.…”

Static form-finding of normal and defective catenaries based on the analytical exact solution of the tensile Euler–Bernoulli beam

“…The initial configuration of the catenary is used not only to simulate the dynamic reaction of the pantograph and catenary 15 but it can also be used to make geometric optimization on the catenary parameters. 16 In addition, the exact solution of the static configuration of a defective catenary is useful to monitor the catenary by pantograph, i.e. when it is possible to simulate the effect of any defect on pantograph acceleration, it would be possible to measure the pantograph acceleration and estimate the type of defect in the catenary.…”