In this paper it is shown a new way to proceed in what concerns to the simulation of high speed railway systems, based on the 1x25 and 2x25 configurations. This approach, relies on highly efficient open source software such as OpenDSS to solve the electrical circuits resulting from the model of the above configurations. Moreover, Python is the open source programming language used as interface with OpenDSS, the processing of the input data and the presentation of results. The effectiveness of the tool is demonstrated with several test cases and a practical system using real traffic data.