Marafão, Fernando Pinhabel [UNESP]Deckmann, Sigmar MaurerMorales Paredes, Helmo Kelis2014-05-272014-05-272008-12-01IEEE Latin America Transactions, v. 6, n. 1, p. 81-88, 2008.1548-0992http://hdl.handle.net/11449/70680This paper discusses the importance of the voltage referential for power quality monitoring and power systempsilas instrumentation. Considering the operating conditions of simple power circuits, it will be demonstrated that an incorrect choice of the voltages referential may result in erroneous quantification of some power quality indices, especially in three-phase four wire circuits. The use of a virtual reference point and the neutral conductor as reference have been considered and the simulation results confirm the influence of the voltage reference selection in the evaluation of total harmonic distortion, unbalance factors and voltage sags. Finally a way of linking both methods will be discussed by means of Blakesleypsilas theorem. © Copyright 2010 IEEE - All Rights Reserved.81-88porFour-wireNeutral conductorOperating conditionPower circuitPower quality indicesPower quality monitoringSimulation resultTotal harmonic distortionsUnbalance factorVirtual reference pointVoltage referenceVoltage sagsElectric wiringQuality controlArtigo10.1109/TLA.2008.4461636Acesso aberto2-s2.0-749491057612-s2.0-74949105761.pdf