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Smart electrical grids today are increasingly integrating new technologies such as electric vehicles, smart metering, and demand side management. They aim to promote the use of renewable energy sources and better energy saving. The ever growing presence of power electronics interfaces, for example photovoltaic panels, batteries, or direct current loads in the power system makes it more vulnerable to power quality issues. The paper aims to create an overview of the existing power quality disturbances in traditional as well as smart grids. The other main objective of the paper is to discuss the techniques to measure and detect supraharmonic emissions in smart grids. The paper also describes the measurement parameters and configurations in smart grid platform in order to analyse the dynamic conditions. This platform is an advanced test facility designed and developed to facilitate the transition from traditional to smart grids. The paper studies the existing power quality disturbances and identified supraharmonic emissions as field of interest. It also presents the design and initial tests conducted on a measurement system for supraharmonics. The parameters and configurations to be performed during the measurements in the smart grid platform are also discussed.

Resistance standards with values in the TΩ range play an important role in electrical instrumentation. The calibration of such standards is, thus, a service offered by many metrology institutes. The techniques used to measure very high resistance values differ quite substantially from the calibration techniques applied in the lower resistance ranges. For this reason, the EURAMET technical committee for electricity and magnetism decided in 2008 to organise for the first time a supplementary comparison of resistance at 1 TΩ and 100 TΩ based on well characterized travelling standards.Eighteen European National Metrology Institutes participated in the comparison. With some exceptions, the results supplied by the participants agree reasonably well with the comparison reference value within the expanded uncertainty.As observed in other resistance comparisons, the characteristics of the standards used as transport artefacts ultimately limit the accuracy of comparisons in this field. The transport behaviour is difficult to model and introduces an undesired bias in the laboratory results. The transport uncertainties are at the level of the uncertainties claimed by some of the participants and, thus, limit the meaningfulness of the comparison results.Another remarkable observation is the big difference in the uncertainty statements made by the participants, even in cases where similar measurement systems were used. The results of the comparison allow the participants to critically review their measurement procedures and uncertainty models.Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/.The final report has been peer-reviewed and approved for publication by EURAMET, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

This paper describes the design of a measurement system for supraharmonic emissions in the frequency range of 2 to 150 kHz, and analyzes the measurements obtained in real grid scenarios. The measurement system is first characterized in the laboratory. The Design of Experiment approach then uses an adequate number of experiments to identify the effects and interactions of factors responsible for supraharmonic emissions. For each of these experiments, the measured supraharmonic emissions are analyzed and quantified using the fast Fourier transform. Next, this data is studied using the Analysis of Variance method, which enables identifying the critical factors that generate supraharmonic emissions in the network. The measurement and analysis results show the individual effects and interactions between these factors.

This paper describes the design of the measurement system for supraharmonic emissions in the frequency range 2-150 kHz in real grid scenarios and factors considered for design. It also portrays the validation of the measurement system on a smart grid platform and the design of experiments performed on this platform. Various network combinations and factors considered for real grid measurements are described in the paper.