Optimisation Of Rolling Stock, Timetable And Traction Power Supply For An Urban Railway System

Abstract

Quite often urban transport systems are legacy systems. The main part of the infrastructure was created a long time ago, while other parts have been upgraded to meet new demands. The introduction of new elements in such a transport system is an issue which should be studied with care. In general, compatibility between all major system elements cannot be guaranteed by compliance with standards or guidelines. While the major part of the traction power supply system (TPS) of the Cascais Line is relatively old, the introduction of new rolling stock, with a considerably higher power demand (higher traction effort, powerful airco units) and a more exacting timetable was contemplated by the train operating company CP. REFER, the infrastructure provider wanted to study the effects of these changes towards catenary and substations carefully. Using the Holland Railconsult simulation tool DITEM®, the Cascais Line has been modelled with a high level of detail, considering track, signalling, catenary, substations, rolling stock and timetable. The existing situation was modelled, the simulation results matched well with the known behaviour. As a next step new types of rolling stock and new timetables were studied. A number of future problems with respect to catenary temperature and loading of substations, and behaviour during disturbances within the TPS System could be predicted. This enabled preemptive measures to be taken. Due to the high level of detail a minimum number of measures could be deduced, which leads to an economical solution. The use of a sophisticated simulation tool proved very useful in the modification and modernisation process of this suburban railway system.