Autor(es)

Asorza, Jesus E. Guevara ; De Azevedo, Walter Luiz Manzi ; De Araujo, Anderson Ricardo Justo ; Colqui, Jaimis Sajid Leon ; Papadopoulos, Theofilos A. ; Filho, Jose Pissolato

• Tipo de documento: Artigo Científico
• Fonte: Electric Power Systems Research; v. 254, p. 10-pg., 2025-12-19.

Resumo

This paper examines the impact of two-layer earth modeling on the electromagnetic behavior of overhead transmission lines (OHTLs), particularly emphasizing the backflashover rate (BFR) and associated transient responses. The study focuses on a 220-kV OHTL subjected to lightning strikes, analyzing key responses such as insulator overvoltages, sky wire overcurrents, and Ground Potential Rise (GPR) at the tower base. The generalized two-layer earth model is considered as reference in the analysis. To approximate this configuration, two Equivalent Homogeneous Earth Models (EHEMs) are employed: the first utilizes the equivalent propagation constant (sigma(eq)), and the second applies the equivalent conductivity (sigma(eq)). Additionally, two homogeneous earth models are included in the analysis, corresponding to the resistivities of the upper and lower soil layers, respectively. The results indicate that the BFR remains nearly unchanged between the two-layer earth model and its corresponding EHEM. However, appreciable differences arise compared to the extreme cases represented by homogeneous soils with resistivity of the upper and bottom layer. Regarding transient behavior, the backflashover inception time is significantly influenced by the soil stratification model, highlighting the importance of accurately representing subsurface conditions. Furthermore, results show that higher soil resistivity reduces lateral current flow to adjacent towers, increasing current injection into the local grounding system and GPR, which lowers the insulator string overvoltage. (AU)

• Processo FAPESP: 21/11258-5 - Centro de Pesquisa em Engenharia para a Mobilidade Aérea do Futuro (CPE-MAF)
• Beneficiário: Domingos Alves Rade
• Modalidade de apoio: Auxílio à Pesquisa - Programa Centros de Pesquisa Aplicada
• Processo FAPESP: 19/01396-1 - Representação de torres convencionais e elevadas de linhas de transmissão diretamente no domínio do tempo para análises de transitórios eletromagnéticos
• Beneficiário: Anderson Ricardo Justo de Araújo
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 23/05066-1 - Estudo das sobretensões transitórias em linhas de transmissão subterrâneas e subaquáticas considerando modelos rigorosos do cálculo dos parâmetros de retorno do solo
• Beneficiário: Jesus Enrique Guevara Asorza
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 24/14472-6 - Estudo de descargas atmosféricas em linhas de transmissão mistas aéreas-subterrâneas usando formulações rigorosas para calcular os parâmetros de retorno do solo.
• Beneficiário: Jesus Enrique Guevara Asorza
• Modalidade de apoio: Bolsas no Exterior - Estágio de Pesquisa - Mestrado