Discussion on DC and AC power quality assessment in railway traction supply systems

The assessment of the power quality could be a valuable tool to foster the efficiency of the whole railway system by 'awarding' the good power quality delivered and absorbed. Power quality is a well-addressed topic in conventional AC 50/60 Hz power systems and many procedures, algorithms and measurement systems were presented in international standards and widely discussed in the scientific literature. A less explored research field is the assessment of the power quality in the railway traction supply systems, through standardized monitoring techniques, in particular with reference to the DC and 16.7 Hz systems. This paper explores this theme verifying if main aspects of the standard measurement procedures and the definitions of some of main power quality indexes, well defined and widely used for conventional power systems, can be used also in railway traction supply systems with minor modifications.