An update on the performance of reactive energy meters under non-sinusoidal conditions

Abstract

The different reactive power and energy metering methods used by electric energy meters on medium and high voltage consumers present different results between themselves, notably in the presence of distorted voltage and current signals. Over recent decades, many discussions and various propositions have been put into action, all of which aimed at a worldwide unification of power and reactive energy metering methods. However, the problem still persists and the objective of this study therefore lies in performing of a quantitative update, concerning the impacts of these different methods on the reactive energy metering for billing purposes. In this context, each of the methods frequently used by the electric energy meter manufacturers will be covered in an analytical manner, seeking the mathematical understanding of the divergences that exist between them. In concurrent fashion, calibration tests will be performed in the laboratory aimed at the correct quantification of measurement deviations found under specific distortion conditions in voltage and current waveforms, when comparing meters from different manufacturers and models. A new electric energy meter, that contemplates all known metering methods, was developed with the aim of performing a measurement campaign allowing for the comparison of the performance of each one of these methods under real load conditions, considering many different types of consumer. The obtained results, in addition to providing a quantitative update of the magnitude of existing deviations, also demonstrate a great concern regarding the lack of isonomy currently found around the world in the metering of reactive power and energy.