Influence of approximate internal impedance formula on half-wavelength transmission lines

Autor(es)

Asorza, J. E. Guevara ; Rojas, R. E. ; Filho, J. Pissolato

• Tipo de documento: Artigo Científico
• Fonte: Electric Power Systems Research; v. 251, p. 7-pg., 2025-09-19.

Resumo

This paper evaluates the impact of using approximate versus exact internal impedance formulations in Overhead Transmission Lines (OHTL), focusing on Half-Wavelength Transmission lines (HWTL) and high-surge impedance loading applications, where multiple conductors per phase are employed. Approximate formulations for the internal impedance of conductors simplify calculations but may introduce minor errors that, in specific applications, can become more significant. These inaccuracies affect key parameters, including active power transfer, surge impedance loading (SIL), and Joule losses, and can also compromise the accuracy of transient analysis. The study compares approximate and exact impedance formulations under steady-state and transient conditions across three OHTL configurations of varying designs. Results reveal that approximate formulations reduce accuracy in SIL and voltages calculations, resulting in potential power transfer limitations and increased voltage drops. Furthermore, a statistical analysis of switching manoeuvres demonstrates that the approximate model predicts higher overvoltages than the exact formula, with phase C exhibiting the most significant deviations. These findings underscore the critical importance of precise internal impedance modelling in HWTL studies to ensure reliable power system analysis. (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: 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
• 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