Influência da resistividade do solo no desempenho de malhas de aterramento em uma rede de distribuição do tipo t2f

Abstract

Recently a new three-phase rural distribution network model was proposed, the T2F (three phase two-wire), which uses two overhead cables for two phases and the ground as the third phase. The third phase makes use of a ground to conduct currents in the ground, however when there is injection of currents into the ground there may be an induction of dangerous surfaces. For this system to operate better and not cause material or moral damage or risks, one of the main steps is the adequate dimensioning of the grounding. One of the grounds that may be used in the construction of this network is the mesh. The design of this type of grounding is presented in standards such as IEEE 80 (2013) and NBR 15751 (2013). These documents indicate that the first stage of the project is to determine the resistivity of the soil where the mesh must be installed. Resistivity only influences several calculations of the grounding project; if its value is not evaluated correctly, the grounding mesh may have its effectiveness compromised. Therefore, this work seeks to evaluate the influence of soil resistivity on the performance of grounding grids, which can be used in a T2F distribution network.