Validity of RLC Equivalent Circuit of Grounding Electrodes in Combination with Equivalent Resistivity in Two-layer Soils and Its Application in Transient Analysis of Arrester-Connected Overhead Lines under Lightning Strike

Document Type : Original Article

Authors

1 Instructor, Department of Electrical Engineering, Faculty of Engineering, Arak University, Arak, Iran

2 Assistant Professor, Department of Electrical Engineering, Faculty of Engineering, Arak University, Arak, Iran

Abstract

In this paper, approximate and exact equivalent circuits for grounding electrodes buried in horizontally two-layered soils are introduced. In the approximate one,  two-layer soil is approximated with equivalent resistivity and then the grounding electrode is modelled with RLC equivalent circuit, while in the exact one, the input impedance of the grounding electrode is first computed in the frequency domain via numerical solution of Maxwell’s equations. Then the input impedance is replaced with rational functions and finally the equivalent circuit in time domain is achieved. In order to extract the validity range of the approximate circuit in two-layer soils, transient analysis of overhead line terminated to arrester in the presence of two-layer soils is carried out where the grounding electrodes are modelled with approximate and exact circuits. The simulation results show that when the thickness of the first layer is less than 1 meter or greater than 40 meter, the approximate circuit yields acceptable results. In addition, sensitivity analysis is carried out on the thickness of the first layer with respect to the single-layer soil. The simulation results show that when the thickness is greater than 40 meter, the two-layer and single-layer soils have the same behavior.

Keywords


[1]     J. Mahseredjian, S. Dennetiere, L. Dube, B. Khodabakhchian, and L. Gerin-Lajoie, “On a new approach for the simulation of transients in power systems,” Elect. Power Syst. Res., vol. 77, no. 11, pp. 1514–1514, 2007.##
[2]     L. Grcev, “Modeling of Grounding Electrodes under Lightning Currents,” IEEE Transaction on Electromagnetic Compatibility, vol. 51, no. 3, pp. 559-571, 2009.## 
[3]     M. Mokhtari, Z. Abdul-Malek, and Z. Salam, “An Improved Circuit-Based Model of a Grounding Electrode by Considering the Current Rate of Rise and Soil Ionization Factors,” IEEE Transaction on. Power Delivery, vol. 21, no. 1, pp. 1-9, 2015.##
[4]     B. Gustavsen and A. Semlyen, “Rational Approximation of Frequency Domain Responses By Vector Fitting,” IEEE Transaction on Power Delivery, vol. 14, no. 3, pp. 1051-1061, 1999.##
[5]     A. Shoory, A. Mimouni, F. Rachidi, V. Cooray, R. Moini, and S. H. H. Sadeghi, “Validity of simplified approaches for the evaluation of lightning electromagnetic fields above a horizontally stratified ground,” IEEE Trans. Electromagn. Compat., vol. 52, no. 3, pp. 657–663, 2010. ##
[6]     C. F. Barbosa, J. O. S. Paulino, and W. C. Boaventura, “A time-domain method for the horizontal electric field calculation at the surface of twolayer earth due to lightning,” IEEE Trans. Electromagn. Compat., vol. 55, no. 2, pp.    371–377, 2013. ##
[7]     H. Karami, K. Sheshyekani, and F. Rachidi,                “Mixed-potential integral equation for full-wave modeling of grounding systems buried in a Lossy multilayer stratified ground,” IEEE Trans Electromagn Compat., vol. 59, no. 5, pp. 1505-15013, 2017. ##
[8]     K. Sheshyekani, S. H. Hesamedin Sadeghi, R. Moini, F. Rachidi, and M. Paolone, “Analysis of transmission lines with arrester termination, considering the        frequency-dependence of grounding systems,” IEEE Transaction on Electromagnetic. Compatibility, vol. 51, no. 4, pp. 986-994, 2009.##
[9]     K. Sheshyekani and L. Paknahad, “Lightning electromagnetic fields and their induced voltages on overhead lines: the effect of a horizontally stratified ground,” IEEE Transactions on Power Delivery, 10.Il09/ TPWRD. 2014. 2329902, in press, 2014. ##
[10]  D. A. Tsiamitros, G. K. Papagiannis, and P. S. Dokopoulos, “Homogenous Earth Approximation of Two-Layer Earth Structures: An Equivalent Resistivity Approach,” IEEE Trans. on Power Delivery, vol. 22, no. 1, pp. 658-666, 2007.##
[11]  J. Osvaldo et al., “An Approximate Expression for the Equivalent Resistivity of a Two-Layer Soil,” 2013 International Symposium on Lightning Protection (XII SIPDA), Belo Horizonte, Brazil, October 7-11, 2013.##
[12]  M. W-Wik, “Double exponential models for comparison of lightning, nuclear and electrostatic discharge spectra,” Proc. 6th Symp. Tech. Exhib. Electromagn. Compat, Mar. 5–7, Zurich, pp. 169–174, 1985.##
[13]  J. A. Martinez, et al, “Parameters determination for Modeling Systems Transients-Part V: Surge Arrester,” IEEE Trans on Power Delivery, vol. 20, no. 3, pp. 2073-2078, 2005.##
[14]  S. Mehrabi and S. R. Ostadzadeh, “Impact of Ocean-Land Mixed Propagation Path on Equivalent Circuit of Grounding Rods,” Journal of Communication Engineering, vol. 8, no. 2, pp. 1-11, 2019.##
[15]  R. F. Harrington, “Field Computation by Moment Methods,” Macmillan, New York, 1968.##
[16]  O. Kherif, et al, “Time-Domain Modeling of Grounding Systems’ Impulse Response Incorporating Nonlinear and Frequency-Dependent Aspects,” IEEE Transactions on Electromagnetic Compatibility, vol. 60, no. 4, pp. 907-918, 2018.##
[17]  B. Zhang, J. Wu, Jinliang He, and R. Zeng, “Analysis of transient performance of grounding system considering soil ionization by the time domain method,” IEEE Transactions on Magnetics, vol. 49, no. 5, pp. 1837-1840, Feb. 2013.##
[18]  IEEE Guide for Application of Insulation Coordination, IEEE Standard 1313.2, 1999.##
[19]  H. Yazdi, S. R. Ostadzadeh, and F. Taheri Astaneh, “Transient Analysis of Single-Conductor Overhead Lines Terminated to Grounded Arrester Considering Frequency Dependence of Electrical Parameters of Soil using Genetic Algorithm,” Journal of Applied Electromagnetics, vol. 3, no. 2, pp. 35-42, 2015. (In Persian)##