Analysis of the Harmonic Distortion and the Effects of Attenuation and Diversity in Residential Areas

This work analyzes the waves of currents in residential loads, evaluating the effects of attenuation and diversity in the cancellation of harmonics, pondering their influence in the prediction of distortion indexes in a distribution system. Starting from signals of currents registered in laboratory and subsequently treated with Fast Fourier's Transformation, the loads were modeled like sources of fixed currents to be combined and simulated with the "Electromagnetic Transient Program" (EMTP), determining the resulting index of harmonic distortion. With models of nonlinear loads inserted in a distribution system, the diversity and attenuation phenomena were evaluated in the EMTP, in the following stages: connection of identical loads (with equal and different powers) and variations in the impedance parameters of the distribution network. The results found verify the fact that the rejection of such phenomena can cause an overestimation of harmonics in a distribution system.