An improved model for soil ionization around grounding system and its application to stratified soil

详细信息    查看全文

• 作者：Liu ; Yaqing ; Theethayi ; Nelson ; Thottappillil ; Rajeev ; M. Gonzalez ; Raul ; Zitnik ; Mihael
• 关键词：Grounding system ; Soil ionization ; Lightning protection
• 刊名：Journal of Electrostatics
• 出版年：2004
• 出版时间：March, 2004
• 年：2004
• 卷：60
• 期：2-4
• 页码：203-209
• 全文大小：322 K

文摘

An improved model for taking into account the effect of the soil ionization around grounding system under lightning strike is proposed in this paper. In this model, the soil ionization region is assumed to retain 7 % of its pre-ionization resistivity, which is consistent with the experimental results on soil ionization found in literature (Trans. SA Inst. Electr. Eng. (1988) 63; AIEE Trans. 61 (1942) 349; Proc. IEE 121(2) (1974) 123) and our own laboratory experiments (Time domain modelling of the response of grounding systems subjected to lightning currents, Licenciate Thesis, Uppsala University, 2003). Compared with modelling the soil ionization as an increase in the size of the ground conductor, the model presented here will not overestimate the beneficial influence of the soil ionization in reducing the ground potential rise, especially in high resistivity soil. The model is also applied to study the transient behaviour of grounding conductors in stratified soil under lightning strike including soil ionization. It shows that making the grounding conductor to penetrate the lower resistivity soil layer could help to decrease the ground potential rise at the injection point several times.