Computer Analysis of Electromagnetic Transients in Grounding Systems Considering Variation of Soil Parameters with Frequency

Marco A. O. Schroeder, Márcio M. Afonso, Tarcísio A. S. Oliveira, Sandro C. Assis

Department of Electrical Engineering, Federal Center of Technological Education of Minas Gerais, Belo Horizonte, Brazil.
Department of Electrical Engineering, Federal Center of Technological Education of Minas Gerais, Belo Horizonte, Brazil; 3Energetic Company of Minas Gerais, Belo Horizonte, Brazil.
Department of Electrical Engineering, Federal University of S?o Jo?o del-Rei, Laboratory of Applied Electromagnetism, S?o Jo?o del-Rei, Brazil.
Energetic Company of Minas Gerais, Belo Horizonte, Brazil..

DOI: 10.4236/jemaa.2012.412066                

Abstract

This paper presents a mathematical model to calculate transients in grounding systems. The derived equations arise from direct application of basic electromagnetic equations in frequency domain, whose solution is obtained by the application of the Moment Methods. A formulation based on experimental measurements is applied to quantify the soil parameters for each frequency. The unified approach is applied in the calculation of the grounding impedance of horizontal electrodes. Results show that the inclusion of frequency dependence of the soil parameters leads to a reduction of the values of grounding impedance, in comparison with results for soils with parameters independent of frequency.

Keywords

Grounding Electrodes; Grounding Impedance; Transient Response; Frequency Response; Electromagnetic Modeling

Conflicts of Interest

The authors declare no conflicts of interest.

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