Analysis of lightning-radiated electromagnetic fields in the vicinity of lossy ground

An antenna theory (AT) approach in the frequency domain is presented to compute electromagnetic fields radiated by a lightning return stroke. The lightning channel is modeled as a lossy-wire monopole antenna (a wire antenna with distributed resistance) energized by a current source at its base, and the ground is modeled as a lossy half-space. The method of moments is used for solving the governing electric field integral equation (EFIE) in the frequency domain. The resultant current distribution along the channel is used to calculate electromagnetic fields at different distances from the channel. All field components are evaluated using a rapid but accurate procedure based on a new approximation of Sommerfeld integrals. In contrast with the previous models, the approach proposed here is characterized by a self-consistent treatment of different field components in air or on the surface of a lossy half-space. It is shown that the omission of surface wave terms in the general field equations, as done in the perfect-ground approximation, can strongly affect model-predicted field components.

[1]  K. Norton,et al.  The Propagation of Radio Waves over the Surface of the Earth and in the Upper Atmosphere , 1937, Proceedings of the Institute of Radio Engineers.

[2]  T. Takashima,et al.  Calculation of Complex Fields in Conducting Media , 1980, IEEE Transactions on Electrical Insulation.

[3]  Yoshihiro Baba,et al.  Characteristics of electromagnetic return-stroke models , 2003 .

[4]  Farhad Rachidi,et al.  Formulation of the field-to-transmission line coupling equations in terms of magnetic excitation field , 1993 .

[5]  Vladimir A. Rakov,et al.  A new lightning return stroke model based on antenna theory , 2000 .

[6]  Vernon Cooray,et al.  Effects of propagation on the rise times and the initial peaks of radiation fields from return strokes , 1983 .

[7]  J. R. Wait.  On the wave tilt at high frequencies-a personal view , 1997 .

[8]  M. Uman,et al.  Lightning return stroke current models with specified channel‐base current: A review and comparison , 1990 .

[9]  Vladimir A. Rakov,et al.  Application of the antenna theory model to a tall tower struck by lightning , 2003 .

[10]  Leonid Grcev,et al.  Computer analysis of transient voltages in large grounding systems , 1996 .

[11]  R. Thottappillil,et al.  Comparison of lightning return‐stroke models , 1993 .

[12]  A. Sommerfeld.  Über die Ausbreitung der Wellen in der drahtlosen Telegraphie , 1909 .

[13]  Yoshihiro Baba,et al.  On the transmission line model for lightning return stroke representation , 2003 .

[14]  Yoshihiro Baba,et al.  Numerical electromagnetic field analysis of lightning current in tall structures , 2001, 2001 Power Engineering Society Summer Meeting. Conference Proceedings (Cat. No.01CH37262).

[15]  Irene A. Stegun,et al.  Handbook of Mathematical Functions. , 1966 .

[16]  Ronold W. P. King,et al.  The electromagnetic field of a vertical electric dipole over the Earth or sea , 1994 .

[17]  Vernon Cooray,et al.  Underground electromagnetic fields generated by the return strokes of lightning flashes , 2001 .

[18]  Vladimir A. Rakov,et al.  Comment on “Return stroke transmission line model for stroke speed near and equal that of light’ by R. Thottappillil, J. Schoene, and M. A. Uman , 2002 .

[19]  V. Rakov,et al.  Comparison of electromagnetic models of lightning return strokes using current and voltage sources , 2003 .

[20]  Vernon Cooray,et al.  Horizontal fields generated by return strokes , 1992 .

[21]  A. Baños.  Dipole radiation in the presence of a conducting half-space , 1966 .

[22]  V. Rakov,et al.  Lightning: Physics and Effects , 2007 .

[23]  James R. Wait,et al.  Concerning the horizontal electric field of lightning , 1997 .

[24]  J. Richmond,et al.  Rigorous field expressions for piecewise-sinusoidal line sources , 1969 .

[25]  Weng Cho Chew,et al.  Accurate analysis of wire structures from very-low frequency to microwave frequency , 2002 .

[26]  M. Ianoz,et al.  Influence of a lossy ground on lightning-induced voltages on overhead lines , 1996 .

[27]  James R. Wait.  Transient Fields of a Vertical Dipole Over a Homogeneous Curved Ground , 1956 .

[28]  Raj Mittra,et al.  An efficient approach for evaluating Sommerfeld integrals encountered in the problem of a current element radiating over lossy ground , 1980 .

[29]  L. Grcev.  Computation of transient voltages near complex caused by ligntning currents , 1992, International Symposium on Electromagnetic Compatibility.

[30]  G J Burke,et al.  Numerical Electromagnetic Code (NEC) - Method of Moments. A User-Oriented Computer Code for Analysis of the Electromagnetic Response of Antennas and Other Metal Structures. Part III. User's Guide. Volume 2. Revised. , 1977 .

[31]  Weng Cho Chew,et al.  Accurate model of arbitrary wire antennas in free space, above or inside ground , 2000 .

[32]  Vernon Cooray.  Some considerations on the "Cooray-Rubinstein" formulation used in deriving the horizontal electric field of lightning return strokes over finitely conducting ground , 2002 .

[34]  Vladimir A. Rakov,et al.  Review and evaluation of lightning return stroke models including some aspects of their application , 1998 .

[35]  Weng Cho Chew,et al.  Modeling of arbitrary wire antennas above ground , 2000, IEEE Trans. Geosci. Remote. Sens..

[36]  M. Rubinstein,et al.  An approximate formula for the calculation of the horizontal electric field from lightning at close, intermediate, and long range , 1996 .

[37]  J. Wait.  The ancient and modern history of EM ground-wave propagation , 1998 .

[38]  Ronold W. P. King.  Electromagnetic field of a vertical dipole over an imperfectly conducting half‐space , 1990 .

[39]  K. K. Mei,et al.  Numerical approximations of the Sommerfeld integral for fast convergence , 1978 .

[40]  S. Visacro,et al.  Evaluation of current distribution along the lightning discharge channel by a hybrid electromagnetic model , 2004 .

[41]  V. Rakov,et al.  Distribution of charge along the lightning channel : Relation to remote electric and magnetic fields and to return-stroke models , 1997 .