Energy loss comparison between 750 VDC and 1500 VDC power supply systems using rail power simulation


S. Açıkbaş and M. T. Söylemez


Int. Conf. on Comp. Aided Design, Manufacture, and Operation in the Railway and Other Advanced Transit Systems (COMPRAIL 2004)


Dresden, Germany


May 2004


multi-train simulation, DC rail traction systems, 1500 VDC


When a new transit line is to be built, apart from many other aspects, it is also necessary to study alternatives of traction power supply system.  One aspect to be studied in calculating the operational cost is the estimated level of electricity cost.

If the line capacity exceeds 22000 pphpd (Passenger Per Hour Per Direction), i.e. medium sized transport capacity, train-set configuration will consist of more than 4 vehicles, and headway time between the trains will get narrower, which results in greater traction energy demand.  Energy loss in a conductor is proportional to square of current drawn from it.  As a result, in theory, doubling the voltage level reduces the energy losses to one quarter.  This might not be correct due to regenerative braking energy.