Análise Comparativa de Modelos do Fenômeno da Ionização do Solo nos Aterramentos das Redes Aéreas de Distribuição

• Autor(a) principal: Almaguer, Hugo Armando Dominguez
• Data de Publicação: 2021
• Outros Autores: Velho, Murilo, Orsi, Alexandre, Coelho, Vilson Luiz
• Tipo de documento: Artigo
• Idioma: por
• Título da fonte: Revista de Engenharia e Pesquisa Aplicada
• Texto Completo: http://revistas.poli.br/index.php/repa/article/view/1730

This paper analyzes the behavior of the overvoltage levels on the primary side of overhead distribution lines considering the phenomenon of soil ionization at grounding under lightning condition. To this end, two formulations were evaluated: The Dynamic and the Geometric Models. Both were implemented by using MODELS, a tool available in the Alternative Transient Program (ATP), a software for the analysis of power systems. Thus, MODELS/ATP replace the fixed value commonly used to represent the resistance of grounding topologies. The case studied corresponds to a section of a compact type of overhead distribution power network, with real parameters practiced by power utilities. The simulations were carried out considering three situations: 1 - not taking into account the phenomenon of soil ionization and the grounding being represented by a resistance of constant value (situation generally found in practice); 2 – considering soil ionization by the Dynamic Model; 3 – considering soil ionization by the Geometric Model. It was found that the effects of ionization drastically alter the behavior of the soil resistivity and the grounding resistance during the transient period of the discharge. Consequently, a significant decrease of the overvoltage levels in the network structures happed, when compared to the situation that uses a fixed resistance value to represent the grounding. In this way, the results show that the adequate representation of the grounding when overhead distribution networks are struck by lightning allow a more realistic analysis and should not be ignored.