Requirement
Over the past few years, technological developments in power electronics have allowed locomotives to be powered via a new generation of converters. One consequence of the arrival of this new equipment has been the appearance of harmonic currents which circulate in electric railway lines at harmonic values which had not previously been present.
It is therefore necessary to be able to ascertain whether or not, in certain configurations, it was possible for these currents to create undesirable overvoltage incidents, leading to cuts in the power supply and possibly damaging equipment.
Change in the amplitude of the voltage with frequency at various points on a railway infrastructure
Realization
CAPSIM developed software, fitted with a user-friendly graphic interface, which was able to calculate the voltage amplitude for each harmonic over a section of electric railway line being traversed by trains.
Some precise and complex physical models have been programmed and implemented, such as the skin effect, proximity effect and the distribution of the return current in the ground, in order that the tool can be representative up to high frequencies.
The tool is capable of representing the major types of locomotive and the majority of sections of railway line which exist in France.
Results
This tool makes it possible for SNCF engineering to identify incompatibilities between railway infrastructure and rolling stock.
An interface window from the tool
