Influência dos Planos de Terra durante o Ensaio de Corona Visual em Arranjo Isolante para Linha Aérea de Transmissão de 500 kV

Abstract

Technical compliance of insulating arrangements of overhead transmission lines is traditionally validated by carrying out electrical tests in high-voltage laboratories. With limited technical and financial resources, these tests are mostly carried out in closed laboratory environments through a simplified single- phase reproduction of the transmission system. By normative recommendation, these single-phase test reproductions must foresee the influence of the adjacent phases of the original system through the positioning of panels acting as ground planes. Seeking to evaluate the correspondence between the critical electric field strength and the inception and extinction of visual corona voltage, as well as the distance factor for the ground planes, the article makes a case study of the positioning of these reflection planes and the arrangement mounting height. Using Finite Element Analysis, the simulation results show that the distance of the reflection planes can alter the electric field levels on the surface of conductors in the order of 18%.