Calculation of ground resistance and step voltage for buried ground rod with insulation lead

Abstract Procedures for installing ground rods can be categorized into the driven ground rod methods and the buried ground rod methods. The leads of ground rods are also classified into two types—bare conductor leads and insulation leads. The analytical results herein elucidate a method for determining ground resistance, earth surface voltage, position and magnitude of the maximum step voltage for the buried ground rod with the insulation lead. The ground resistance, earth surface voltage and step voltage in the driven ground method exceed those of the buried ground rod with the insulation lead. Ground resistance, earth surface voltage and step voltage decrease as the depth of the buried ground rod increases. The position of the maximum step voltage varies with the buried depth of a ground rod with the insulation lead. The distance of the maximum step voltage from the ground rod increases with the depth of the buried ground rod. Results of this study provide a valuable reference for ground designs that protect humans and electrical equipment.

[1]  Cheng-Nan Chang,et al.  Comparison of 161/69-kV grounding grid design between indoor-type and outdoor-type substations , 2005 .

[2]  Lin Zhou-bu.  ANSI/IEEE Std 446-1995 IEEE Recommended Practice for Emergency and Standby Power Systems for Industrial and Commercial Applications , 2007 .

[3]  Chien-Hsing Lee.  Safety assessment of bulk and traction supply substations in Taipei rail transit systems , 2004 .

[4]  D.R. Stockin.  Design and testing of facilities ground , 2000, Electrical Overstress/Electrostatic Discharge Symposium Proceedings 2000 (IEEE Cat. No.00TH8476).

[5]  I. A. Reid.  Book review: IEEE Guide for Safety in AC Substation Grounding—ANSI/IEEE Std. 80-1986 , 1988 .

[6]  Jinliang He,et al.  Safety analysis of grounding grid for substations with different structure , 2000, PowerCon 2000. 2000 International Conference on Power System Technology. Proceedings (Cat. No.00EX409).

[7]  J. G. Sverak.  Progress in step and touch voltage equations of ANSI/IEEE Std 80-historical perspective , 1998 .

[8]  J.A. Guemes-Alonso,et al.  A practical approach for determining the ground resistance of grounding grids , 2006, IEEE Transactions on Power Delivery.

[9]  Chien-Hsing Lee,et al.  Comparison of touch and step voltages between IEEE Std 80 and IEC 479-1 , 1999 .

[10]  C. J. Blattner.  Study of Driven Ground Rods and Four Point Soil Resistivity Tests , 1982, IEEE Transactions on Power Apparatus and Systems.

[11]  Zhou Bihua,et al.  Calculation of step voltage near lightning current , 2004, 2004 Asia-Pacific Radio Science Conference, 2004. Proceedings..

[12]  Chien-Hsing Lee,et al.  A graphical method for safety assessment of grounding systems , 2000, 2000 IEEE Power Engineering Society Winter Meeting. Conference Proceedings (Cat. No.00CH37077).

[13]  Y. L. Chow,et al.  A fast and accurate analysis of grounding resistance of a driven rodbed in a two-layer soil , 1996 .

[14]  Chien-Hsing Lee,et al.  Computation of current-division factors and assessment of earth-grid safety at 161/69-kV indoor-type and outdoor-type substations , 2005 .

[15]  U. Grasselli,et al.  Measurements of touch and step voltages adopting multi current auxiliary electrodes , 2000, Conference Record of the 2000 IEEE Industry Applications Conference. Thirty-Fifth IAS Annual Meeting and World Conference on Industrial Applications of Electrical Energy (Cat. No.00CH37129).

[16]  E. Sunde.  Earth conduction effects in transmission systems , 1949 .

[17]  M.M.A. Salama,et al.  Surface Voltages and Resistance of Grounding Systems of Grid and Rods in Two-Layer Earth by the Rapid Galerkin's Moment Method , 1997, IEEE Power Engineering Review.

[18]  M. Popov,et al.  On high-frequency circuit equivalents of a vertical ground rod , 2005, IEEE Transactions on Power Delivery.

[19]  T. Takahashi,et al.  Calculation of earth resistance for a deep-driven rod in a multi-layer earth structure , 1991, IEEE Power Engineering Review.

[20]  Chien-Hsing Lee,et al.  Safety assessment of AC earthing systems in a DC traction-supply substation , 2005 .

[21]  S. Bourg,et al.  Deep earth electrodes in highly resistive ground: frequency behaviour , 1995, Proceedings of International Symposium on Electromagnetic Compatibility.

[22]  J. Nahman,et al.  A practical method for the interpretation of earth resistivity data obtained from driven rod tests , 1988 .

[23]  M. Mitani,et al.  Theoretical analysis of grounding resistance for the rod buried into the multilayered earth , 2000, 2000 Power Engineering Society Summer Meeting (Cat. No.00CH37134).