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http://dx.doi.org/10.15683/kosdi.2022.3.31.019

A Study on How to Lower the Grounding Impedance by Needles-typed Grounding Rods  

Park, Sung-Yeol (Department of Industrial Engineering, Sunmoon University)
Publication Information
Journal of the Society of Disaster Information / v.18, no.1, 2022 , pp. 19-28 More about this Journal
Abstract
Purpose: One of the methods for preventing disasters such as fire, explosion, and electric shock caused by electricity is to perform grounding. In case of the grounding current includes a frequency component having a high, it is preferable to measure grounding impedance rather than grounding resistance. This study proposes countermeasures to reduce grounding impedance to suppress an ground potential rise due to a grounding current having a frequency component of several kHz or more. Method: General grounding rods and needles-typed grounding rods were buried in the ground, and grounding resistance and grounding impedance were measured, respectively. The characteristics of grounding impedance according to frequency were identified. Result: There was little difference in the measurement results of the grounding resistance between general grounding rods and needles-typed grounding rods. In a frequency range lower than 62.5kHz, there was little difference in the measurement results of the grounding resistance between general grounding rods and needles-typed grounding rods. In a frequency range higher than 62.5kHz, the grounding impedance of needles-typed grounding rods was reduced by about 15% than the grounding impedance of general grounding rods. Conclusion: In the commercial frequency domain, it is effective to connect several grounding rods (common grounding) to lower the grounding resistance value. In the frequency domain of several kHz or more, it is expected that needles-typed grounding rods can effectively reduce the ground potential rise due to the grounding current.
Keywords
Disaster; Grounding Resistance; Grounding Impedance; Ground Potential Rise; General Grounding Rods; Needles-typed Grounding Rods;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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1 Framework Act on the Management of Disasters and Safety (2020). Ministry of the Interior and Safety.
2 Kim, H.Y., Jang, U.B. (2017). "A study on the safety grounding for prevention of electric shock hazard in construction of industrial plant in maritime landfill area." Journal of the Korea Society of Disaster Information, Vol. 13, No. 1, pp. 21-27.
3 Lee, B.H., Eom, J.H. (2004). "Analysis of the frequency dependent characteristics og ground impulse of a ground rod." The Korean Institute of Electrical Engineers, Vol. 53C, No. 8, pp. 426-432.
4 Seo, J.S., Park, H.C., Kil, G.S., Oh, J.G. (2013). "Comparative Analysis on Ground Impedance for a Carbon Block and a Copper Rod." J. KIEEME, Vol. 26, No. 6, pp. 472-477.
5 Choi, H.K., Song, Y.J., Oh, J.S., Choi, B.S. (2018). Design of Grounding Facilities. Seongandang Press, Paju, Korea.
6 Gil, H.J., Shong, K.M., Kim, Y.S., Kim, C.M., Kim, Y.J. (2016). "Design and fabrication of high frequency ground impedance measuring system for assessment of grounding system for lightning protection." Journal of the Korean Society of Safety, Vol. 31, No. 3, pp. 47-52.   DOI
7 Kim, D.S., Lee, B.H. (2019). "Potential rises on grounding grid combined with carbon ground electrodes depending on the injection point of impulse currents." Journal of KIIEE, Vol. 33, No. 1, pp. 54-60.
8 Kim, H.J., Kim, H.G., Lee, B.H. (2017). "Ionization characteristics of soil due to impulse voltage." Journal of KIIEE, Vol. 31, No. 6, pp. 54-62.
9 Kim, H.Y., Yoon, S.H. (2018). "A Study on the Safety Characterization Grounding Design of the Inner Photovoltaic System." Journal of the Korea Society of Disaster Information, Vol. 14, No. 1, pp. 1-11.   DOI
10 Lee, B.H., Lee, S.C. (1999). The Major Foundational Technics for Grounding Systems. Uije Press, Seoul, Korea.
11 Park, C.W., Kim, H.G., Lee, B.H. (2017). "Comparison of soil needles discharge Characteristics of ground rod and ground electrode with under impulse voltage." Proceedings of KIIEE Annual Conference, Seoul, p. 69.
12 Yoo, Y.W., Cho, S.C., Lee, B.H. (2014). "Effects of soil discharges on the impulsive ground impedance of ground rod with needles." Journal of KIIEE, Vol. 28, No. 5, pp. 98-105.