Proceedings home preface contents authors keywords copyright reference ©2012 Civil-Comp Ltd				Paper 139 A Study on Multiple Pantograph Operations for High-Speed Catenary Contact J. Pombo, P. Antunes and J. Ambrósio IDMEC/IST, Technical University of Lisbon, Portugal Keywords: railway dynamics, multibody systems, pantograph-catenary interaction, contact forces, virtual homologation. full paper (pdf) - reference The limitation on the top velocity of high-speed trains concerns the ability to supply the proper amount of energy required to run the engines, through the pantograph-catenary interface. As a result of the loss of contact not only the energy supply is interrupted but also the arching between the collector bow of the pantograph and the contact wire of the catenary occurs, leading to the deterioration of the functional conditions of the two systems. Such problems require that the dynamics of the pantograph-catenary are properly modelled and that software used for analysis, design or to support maintenance decisions is not only accurate and efficient but also allows for modelling all details relevant to the train operation. In the great majority of cases, high speed trains are operated with two pantographs in constant contact with the catenary. The purpose is to provide the necessary energy required by the electrical engines in order to keep the trainset running at top operational speeds. Nevertheless, the multiple pantograph operations raise problems that do not occur when using a single pantograph. These issues need to be studied with further detail and include the influence of the leading pantograph over the quality of contact on the rear one. This work uses a fully three-dimensional methodology for the computational analysis of the interaction between catenary and pantographs. The finite element method is used to represent the catenary while a multibody methodology is applied for pantograph modelling. The contact between the two subsystems is described using a penalty contact formulation. The performance of two different pantographs, when running on the same catenary, is studied. Multiple pantograph operation scenarios, with different distances between them, are also analysed. The results presented in this paper show that the passage of the front pantograph affects the performance of the rear one. In fact, as the leading pantograph passes, it originates an excitation of the overhead contact line. Then, when the rear pantograph passes on that location, it will face a perturbed catenary. It was observed that, depending on the distance between pantographs, this influence can be positive or negative when compared with a single pantograph operation. On the other hand, it is observed that the presence of the rear pantograph has a negligible influence on the leading one. It is demonstrated in this paper that the numerical simulation tools provide the means that allow the enhancement of the regulation criteria and consider other operational aspects besides the single pantograph operation. The results also indicate that the questions of compatibility between the pantograph and the catenary in several operational conditions can be addressed using numerical tools, reducing the costs and time required for vehicle homologation.