Transfer standard for the assessment of spurious emissions in DC power

Low-voltage DC grids are becoming more and more popular, thanks to the possibility of integrating greener energy sources. This new power system paradigm, though, is not accounted in the current standardization framework. In particular, the power metering infrastructure is not meant to deal with signals consisting of DC components affected by AC disturbances (as the ones inherent in many renewable energy sources). This paper addresses this problem by means of an extensive measurement campaign, intended to evaluate the effect of AC disturbances on DC power meters. The obtained results point out how the limiting factor in the wide-spread of such DC grids is a lack of a proper metrology infrastructure: spanning from a proper definition of the measurand, up to a rigorous characterization of the meter influence quantities. This analysis poses the basis for a more structured approach towards a reasoned definition of performance targets for DC meters in modern power systems.