Avaliação de Modelagens de Parâmetros de Linhas de Transmissão Considerando a Corrente de Retorno pelo Solo

Abstract

This paper presents the calculation of the longitudinal and transverse parameters of transmission lines, considering the effects of ground return current. To this end, five formulations widely disseminated in the literature were implemented through a developed computational routine. A three-phase transmission line from CEMIG's system was analyzed as an example, comparing different modeling approaches for various soil resistivity values. Sensitivity analyses regarding frequency and soil resistivity variations highlighted the inadequacy of treating the soil as a perfect electrical conductor, particularly in the evaluation of the line's longitudinal resistance, which is highly sensitive to soil effects. Furthermore, the study demonstrates the feasibility of using approximate methods, which require less computational effort and provide satisfactory results, depending on soil characteristics and transmission line configuration.