Estimativa de conteúdo harmônico na fase de projeto de instalações elétricas prediais

Abstract

Appliances and electronics are essential pieces of equipment in people’s daily lives and are mostly made up of power electronics elements. These components are treated as non-linear loads, which due to their electronic structure, generate harmonic currents in the electrical system. Some of the negative effects that the presence of harmonics generated in the electrical installation are: excessive heating, voltage drops resulting from harmonic distortions, activation of protection devices and change in the installation’s power factor. With the aid of an Energy Analyzer and aiming to estimate the harmonic components of some of the most common devices, some isolated equipment and arrangements between them were studied. With the collected data, two methods were elaborated to calculate the harmonic distortion of the current of each device from the calculated individual harmonic spectrum. The method with the most consistent theoretical result to the measured was defined and, using technical standards, the dimensioning of electrical cables in a residence was defined. Thus, through the process of collection, study, review and corrective calculations, it is possible to estimate and take action against this type of harmonic effects.