A Novel Method for Measuring the Ground Impedance using Variable Frequency Inverter

가변주파수 인버터를 이용한 접지임피던스의 새로운 측정기법

  • Published : 2004.05.01

Abstract

In order to analyze the frequency dependance of ground impedance in grounding grids for lightning and surge protection, a novel method for measuring the ground impedance as a function of frequency were experimentally investigated. The experiments were carried out in rectangular grounding grids with $6{\times}8$ conductors of 22 $mm^2$ buried at a depth of 0.5 m. The test current was injected by the variable frequency inverter whose frequency is linearly controlled for the established period in the range of 5∼500 KHz. The amplitude and phase of ground impedance were calculated from the waveforms of the test current and ground potential rise measured by the band-pass filter tuned in a specific frequency. The frequency dependence of ground impedance was mainly caused by the inductive current flowing through grounding conductors over the frequency of 100 KHz. The proposed measurement method of ground impedance would be applicable to evaluate the transient response characteristics in lightning protection grounding systems.

Keywords

References

  1. I. D. Lu, R. M. Shier, 'Application of a Digital Signal Analyzer to the Measurement of Power System Ground Impedance', IEEE Trans. on PAS, Vol. 100, No. 4, pp.1918-1922, 1981 https://doi.org/10.1109/TPAS.1981.316535
  2. A. D. Papalexopoulos, A. P. Meliopoulos, 'Frequency Dependent Characteristics of Grounding System', IEEE Trans. on PAS, Vol. 100, No. 4, pp.1918-1922, 1981 https://doi.org/10.1109/TPAS.1981.316535
  3. 이복희, 이승칠, 접지의 핵심기초기술, 도서출판 義제, 1999, p.64-69, 1981
  4. Mohan, Undeland, Robbins, Power electronics, John Wiley & Sons, 1995, pp.626-634
  5. Muhammad. H. Rashid, Power Electronics, Prentice-Hall, 1993, pp.262-301
  6. 한경희, 황락훈, 이승환, 전력전자공학, 형설출판사, 1997, pp.129-132
  7. IEEE Std 81-1983, IEEE Guide for Measuring Earth Resistivity, Ground Impedance, and Earth Surface Potentials of a Ground System, IEEE, Inc., pp.17-24, 1983
  8. Cheng-gang Wang, T. Takasima, T. Sakuta, Y. Tsubota, 'Grounding resistance measurement using fall-of-potential method with potential probe located in opposite direction to the current probe', IEEE Trans. on PD, Vol. 13, pp.1128-1135, 1998 https://doi.org/10.1109/61.714472
  9. J. Ma, F.P. Dawalibi, 'Effects of inductive coupling between leads in ground impedance measurements using the fall-of-potential method', Transmission and Distribution Conference, 1999 IEEE, Vol. 1, pp.266-271, 1999 https://doi.org/10.1109/TDC.1999.755359
  10. IEEE Std 81-2-1991, IEEE Guide for Measurement of Impedance and Safety Characteristics of Lange, Extended or Interconnected Grounding Systems, IEEE, Inc., pp.17-21, 1991
  11. IEEE Std 81-2-1991 IEEE Guide for Measurement of Impedance and Safety Characteristics of Lange, Extended or Interconnected Grounding Systems