SimuX Applications
Optimum Traction Power Supply Designs
For new and expanding systems, SimuX supports the detailed analyses needed to generate the most cost-effective designs, while ensuring operability under normal and degraded and emergency conditions. Outputs include substation instantaneous and RMS power flows, with RMS values available over various user-selected time windows.

A few other SimuX outputs supporting the traction power design process include:
  • Train voltage levels,
  • Feeder instantaneous and  RMS currents,
  • Running rail voltage rise (“touch potential”) with respect to ground and stray currents

Peak and RMS power loading for each substation in the system, compared with 100% nameplate ratings, allow visual information that all substations are properly sized for a new or reconfigured network.


Lowest train voltages values profile along a heavy metro line.


Highest rail voltage values profile along a heavy metro line.

Traction power systems designed and constructed long ago may require an upgrading, but what would be the most cost-effective capital investment plan? SimuX modelling can determine whether existing substations, OCS/third rail and power cables are adequate or whether some enhancements are required, particularly as service is increased and new vehicles are introduced. A thorough analysis supported by SimuX will reveal the rail system’s strengths and weaknesses, allowing for an integrated and updated new design.


Total traction power demand (in green) and its RMS diagram (in red) for a metro line.

SimuX supports rapid investigation of potential solutions to traction power performance issues – adding a substation, adding parallelling cables, adding feeder wires to catenary system, changing substation “no load” voltages, upgrading the running rails, third rail/catenary or negative return system, or even altering the train schedule (headway or train length or altering maximum speed limits).


Total traction power demand RMS diagram for a day operation of a heavy metro line


Protection settings of a traction power supply system circuit breakers has utmost importance for safe operation of the system. SimuX can model short circuits on the line and allows us to determine close and remote short circuit current values.

Short circuit current diagram along a Light Rail Transit line.