The exchange of braking energy between the trains: Determinist analysis and proposal of a probabilistic one

It is proposed a method to analyse the operation of a metro railway transit line by increasing the energetic exchange between the trains during braking and traction phases. Based on the track profile and on the mechanical and electric characteristics of the trains, a simulation model has been developed to estimate the fraction of electrodynamics braking energy which cannot be recuperated and then is dissipated on board resistors, when no train need to get power from the electric line. The train operation can be optimised by estimating, for a fixed train headway, what is the number of simultaneous operating trains which determines the minimum percentage of the electrodynamics braking energy that cannot be regained, and calculating the relevant energetic savings. The simulations are related to the metro railway line of Catania(Italy), which is under construction by the Circumetnea Railway Company. It is proposed a probabilistic analysis that compared to a determinist one allow to estimate the electric power exchange between trains more simply but with less accuracy.