Prediction, identification and elimination of conducted disturbances in DC supplied traction systems still remain a vital and urgent issue. Modern electric vehicles equipped with power electronic converters are the most important source of conducted disturbances due to generation of high order current harmonics, which can cause malfunction of signalling, command and control infrastructure of a railway line. Although the problem is well reported in the literature and experienced by the manufacturers of new rolling stock which are to be put in service, previously unforeseen disturbances may appear in some cases. The authors present an idea of elimination of that kind of disturbances by applying a monitor of disturbances combined with a control system of power electronic converters of a drive system. Such a solution reduces the level of disturbances and enables the vehicle to maintain the required power and traction force.

electric traction; harmonics; EMC; vehicles; converters; signalling; command and control