Overvoltages Induced in the Supplying Line by an Electric Railway Vehicle

The paper focuses on a railway traction system. A railway vehicle, driven by a.c. three-phase asynchrnnous motors supplied thrnugh inverters from a single phase transformer, is connected to it. A brief description of the single phase a.c. (50 Hz, 25 kV) driving system is prnvided. The traction substation consists in down step voltage transformers supplied from the power system. The single phase traction system, when connected to the three-phase supplying system, intrnduces non-symmetries and cunent harmonics. A 50 km line segment from a simple supplying line was considered for simulation of overvoltages at cunent harmonics. A conect design of the rnilway vehicle driving system must meet the requirements imposed by the standard EN 50388 relative to its connection to the supplying line. Prnctical validation concerning overvoltages is discussed.