The measurement of reactive energy in polluted distribution power systems: an analysis of the performance of commercial static meters

This paper presents a comparative analysis of the performances of both a traditional induction meter and various types of commercial static meters for reactive energy in the presence of harmonic distortion. This is a topical issue, since there are several types of static meters on the market, based on different principles of construction. In accordance with current standards, these meters are designed to operate in sinusoidal conditions and their performance is not tested in the presence of harmonic distortion. However, with the increase of pollution levels in power systems, the meters may be used even in the presence of distorted voltages and/or currents; in such cases, their accuracy may be very different from the nominal conditions, and the various meters may lead to different measurements of energy for the same load conditions. In this paper, the analysis is supported by several experimental tests, performed by means of a power calibrator.