Investigating the validity of existing definitions and empirical equations of effective length/area of grounding wire/grid for transient studies
2007 (English)In: Journal of Electrostatics, ISSN 0304-3886, Vol. 65, no 5-6, 329-335 p.Article in journal (Refereed) Published
There are various definitions for effective length/area of grounding wire/grid for lightning transients [A.S. Farag, T.C. Cheng, D. Penn, Grounding terminations of lightning protective systems, IEEE Trans. Dielectics, Elect. Insul 5(6) (1998) 869–877; B.R. Gupta, B. Thapar, Impulse impedance of grounding grid, IEEE Trans. Power Apparatus Syayem PAS-99(6) (1980) 2357–2362; Y. Liu, N. Theethayi, R. Thottappillil, An engineering model for transient analysis of grounding system under lightning strikes: non–uniform transmission line approach. IEEE Trans. Power Delivery 20 (2) (2005) 722–730; M.I. Lorentzou, N.D. Hatziargriou, Modelling of long grounding conductors using EMTP, in: IPST’99, International Conference on Power System Transients, Budapest, 20–24 June, 1999; L.D. Grcev, M. Heimbach, Frequency dependent and transient characteristics of substation grounding system, IEEE Trans. Power Delivery 12 (1997) 172–178.]. The present work investigates and discusses the validity of those existing definitions. Further, practical methods for estimating the effective length/area of different grounding structures are proposed for engineering applications. The calculations for effective length/area based on non-uniform transmission line approach (Liu et al., 2005) show that, for a single grounding wire, the empirical equation for effective length in Farag et al. (1998) is not valid when the injection current has very fast rise time. Also, the empirical equation for effective length of grid edge in Gupta and Thapar (1980) is not applicable for grids with large inner mesh size.
Place, publisher, year, edition, pages
2007. Vol. 65, no 5-6, 329-335 p.
Grounding wire and grid, Effective length and lightning transient
Engineering and Technology
IdentifiersURN: urn:nbn:se:uu:diva-14000DOI: 10.1016/j.elstat.2006.09.005ISI: 000246039400008OAI: oai:DiVA.org:uu-14000DiVA: diva2:41770