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

DOI: 10.4236/jemaa.2012.412066, PP. 475-480

Keywords: Grounding Electrodes, Grounding Impedance, Transient Response, Frequency Response, Electromagnetic Modeling

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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.

References

[1]  The IEEE Standards Association, “IEEE Guide for Safety in AC Substation Grounding”, The IEEE Standards Association, New York, 2000.
[2]  S. Visacro, “A Comprehensive Approach to the Grounding Response to Lightning Currents,” IEEE Transactions on Power Delivery, Vol. 22, No. 1, 2007, pp. 381-386. doi:10.1109/TPWRD.2006.876707
[3]  L. Grcev and F. Dawalibi, “An Electromagnetic Model for Transients in Grounding Systems,” IEEE Transactions on Power Delivery, Vol. 5, No. 4, 1990, pp. 1773-1781. doi:10.1109/61.103673
[4]  Y. Liu, N. Theethayi and R. Thottappillil, “An Engineering Model for Transient Analysis of Grounding System Under Lightning Strikes: Nonuniform Transmission-Line Approach,” IEEE Transactions on Power Delivery, Vol. 20, No. 2, 2005, pp. 722-730. doi:10.1109/TPWRD.2004.843437
[5]  A. F. Otero, J. Cidrás and J. L. del álamo, “FrequencyDependent Grounding System Calculation by Means of a Conventional Nodal Analysis Technique,”, IEEE Transactions on Power Delivery, Vol. 14, No. 3, 1999, pp. 873878. doi:10.1109/61.772327
[6]  C. M. Portela, “Measurement and Modeling of Soil Electromagnetic Behavior,” Proceedings of IEEE International Symposium on Electromagnetic Compatibility, Seattle, 2-6, August 1999, pp. 1004-1009.
[7]  C. M. Portela, M. C Tavares and J. Pissolato, “Accurate Representation of Soil Behaviour for Transient Studies,” IEEE Proceedings Generation, Transmission and Distribution, Vol. 150, No. 6, 2003, pp. 736-744.
[8]  C. M. Portela, J. B. Gertrudes, M. C. Tavares and J. Pissolato, “Earth Conductivity and Permittivity Data Measurements: Influence in Transmission Line Transient Performance,” Elsevier, Electric Power Systems Research, Vol. 76, No. 11 2006, pp. 907-915. doi:10.1016/j.epsr.2005.11.006
[9]  A. C. S. Lima and C. M. Portela, “Inclusion of FrequencyDependent Soil Parameters in Transmission-Line Modeling,” IEEE Transactions on Power Delivery, Vol. 22, No. 1, 2007, pp. 492-499. doi:10.1109/TPWRD.2006.881582
[10]  C. L. Longmire and K. S. Smith, “A Universal Impedance for Soils,” Defense Nuclear Agency, Washington, DC, 1975.
[11]  J. H. Scott, “Electrical and Magnetic Proprieties of Rock and Soil,” United States Department of the Interior Geological Survey, 1983.
[12]  S. Visacro and R. S. Alípio, “Frequency Dependence of Soil Parameters: Experimental Results, Predicting Formula and Influence on the Lightning Response of Grounding Electrodes,” IEEE Transactions on Power Delivery, Vol. 27, No. 2, 2012, pp. 927-935. doi:10.1109/TPWRD.2011.2179070
[13]  R. S. Alípio, M. A. O. Schroeder, M. M. Afonso, T. A. S. Oliveira and S. C. Assis, “Electric Fields of Grounding Electrodes with Frequency Dependent Soil Parameters,” Electric Power Systems Research, Vol. 83, No. 1, 2012, pp. 220-226. doi:10.1016/j.epsr.2011.11.011
[14]  L. Grcev, “Impulse Efficiency of Ground Electrodes,” IEEE Transactions on Power Delivery, Vol. 24, No. 1, 2009, pp. 441-451. doi:10.1109/TPWRD.2008.923396
[15]  S. Visacro and C. M. Portela, “Soil Permittivity and Conductivity Behavior on Frequency Range of Transient Phenomena in Electric Power Systems,” Proceedings of Symposium High Voltage Engineering, Braunschweig, 24-28 August 1987, pp. 107-112.
[16]  S. Visacro and A. Soares, “HEM: A Model for Simulation of Lightning-Related Engineering Problems,” IEEE Transactions on Power Delivery, Vol. 20, No. 2, 2005, pp. 12061208. doi:10.1109/TPWRD.2004.839743
[17]  A. Soares, M. A. O. Schroeder and S. Visacro, “Transient Voltages in Transmission Lines Caused by Direct Lightning Strikes,” IEEE Transactions on Power Delivery, Vol. 20, No. 2, 2005, pp. 1447-1452. doi:10.1109/TPWRD.2004.839214
[18]  F. H. Silveira and S. Visacro, “The Influence of Attachment Height on Lightning-Induced Voltages,” IEEE Transactions on Electromagnetic Compatibility, Vol. 50, No. 3, 2008, pp.743-747. doi:10.1109/TEMC.2008.926885
[19]  R. S. Alípio, M. A. O. Schroeder, M. M. Afonso and T. A. S. Oliveira, “Electromagnetic Fields of Buried Conductors,” Proceedings of the International Conference on Grounding Earthing, Florianópolis, 11-15 November 2008, pp. 399-402.
[20]  R. F. Harrington, “Field Computation by Moment Methods,” IEEE Press, New York, 1993. doi:10.1109/9780470544631
[21]  T. Takashima, T. Nakae and R. Ishibashi, “Calculation of Complex Fields in Conducting Media,” IEEE Transactions on Electrical Insulation, Vol. EI-15, No. 1, 1980, pp. 1-7. doi:10.1109/TEI.1980.298290

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