Uncertainty estimation for DSP-based power quality measurements

This paper deals with the uncertainty in digital measurement systems designed for power quality applications. The main goal of this work is to evaluate such uncertainty by means of a Monte Carlo method recently proposed in the literature. The accuracy of the measurement result obtained with a DSP-based instrument for power quality metering depends on the behavior of the devices located in both the conditioning block and A/D conversion stage: it is thus necessary to consider the uncertainties introduced by each component of the system and the propagation of their effects through the measurement chain. Here, the uncertainty is estimated starting from the technical specifications provided by the manufacturers of these devices. Experimental results are reported to show the importance of some concerns about the practical implementation of the proposed methodology in a real instrument.