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 catenary-pantograph interface. Due to the loss of contact, not only the energy supply is interrupted, but also 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. An alternative would be to increase the contact force between the two systems. But such force increase would lead to a rapid wear of the contact strip of the pantograph and of the contact wire with negative consequences on the durability of the systems. These situations require that the dynamics of the pantograph-catenary are properly modeled and that software used for analysis, design, or to support maintenance decisions is not only accurate and efficient, but also allows for modeling all details relevant to the train overhead energy collector operation. This work presents a fully three-dimensional methodology for the computational analysis of the interaction between catenary and pantographs. The finite element method (FEM) is used to support the modeling of the catenary, while a multibody (MB) dynamics methodology is applied to support the pantograph modeling. The contact between the two subsystems is described using a penalty contact formulation. A high-speed co-simulation procedure is proposed to ensure the communication between the two methodologies. In order to validate the formulation and models developed, the numerical results are compared against experimental data. The proposed methodology is then applied to study the interaction of multiple pantographs of a high-speed train with the catenary. The results show that the passage of the front pantograph excites the catenary, leading to the deterioration of the contact conditions on the rear one.