Uma proposta para a compensação dinâmica de cargas desequilibradas

Abstract

Ideally, three-phase electrical systems must have voltages and currents with the same magnitude and with an angular phase-shift of 120 °. However, the situations found in the field, as a rule, show dissimilarities between these electric quantities, thus characterizing the well-known unbalanced three-phase systems. This operational condition is due to a number of factors, some intrinsic to the supply systems, and others to the characteristics of the fed loads. In view of the recognized negative impacts associated with improper operations of the networks and their components, as well as effects on the efficiency of the electricity supply and consumption process, regulatory agencies have been aware in relation to this indicator of the electrical power quality. For these reasons, boundary values are often found in national and international regulations. In such circumstances, once such standards are exceeded, measures to mitigate or conform to established power quality standards should be used. To meet these requirements, several strategies are known and available in the market, however, when confronting the benefits with the costs of some solutions, the motivation for the search for more attractive strategies appears. In this way, the present research is focused as the main target in this dissertation, which is aimed at proposing an imbalance compensator based on low-cost commercial static components, associated with a switching and control strategy to suit dynamic conditions normally imposed by the loads. Considering that the research in question is presented as an initial proposition, it is based on its theoretical foundations, and the evaluation process of the effectiveness of its performance is done computationally.