触发闪电环境下地网冲击接地电阻特征分析  

Characteristic of Impulse Grounding Resistance of a Grounding Grid by Triggered Lightning Flash

作　　者：张鹃 王孝波[3] 颜旭[4] 陈绍东[4] ZHANG Juan;WANG Xiaobo;YAN Xu;CHEN Shaodong(School of Atmospheric Sciences,Sun Yat-sen University,Zhuhai,Guangdong 519082,China;Jiangmen Meteorological Service,Jiangmen,Guangdong 529030,China;Guangzhou Meteorological Service,Guangzhou 511430,China;Guangzhou Institute of Tropical and Marine Meteorology,CMA,Guangzhou 510641,China)

机构地区：[1]中山大学大气科学学院,广东珠海519082 [2]江门市气象局,广东江门529030 [3]广州市气象局,广东广州511430 [4]中国气象局广州热带海洋气象研究所,广东广州510641

出　　处：《热带气象学报》2024年第2期208-216,共9页Journal of Tropical Meteorology

摘　　要：基于触发闪电技术,研究了2019年夏季8次触发闪电44次回击、5次初始连续电流脉冲(ICCP)和24次M分量对冲击接地电阻的影响,探索了冲击接地电阻随雷电流注入的动态变化规律。结果发现:闪电放电ICCP、M分量和回击过程冲击接地电阻均小于工频接地电阻,ICCP和叠加在回击回落之后连续电流上的M分量冲击接地电阻略大于回击过程,平均值分别为11.2Ω和10.8Ω。叠加在回击下降沿上的M分量冲击接地电阻平均值7.8Ω,明显小于回击过程,最小值可达2.4Ω。ICCP和M分量冲击接地电阻随电流增加而减小,回击过程与电流峰值没有明显的相关性。叠加在回击下降沿上的M分量冲击接地电阻随雷电流峰值、背景电流值的增加呈指数衰减关系,还与之前回击电流峰值成一定的反比例关系。随着闪电回击电流的注入,冲击接地电阻呈现动态变化过程,小电流在回击峰值下降后出现一个缓慢增长的过程,大电流在回击峰值下降后出现一个快速下降的过程。闪电不同物理过程火花和电感效应的作用是不同的,两者共同作用决定了土壤的电离程度,从而决定了冲击接地电阻的大小和变化。In this paper,based on the triggered lightning technique,the impact of impulse grounding resistance was studied for 44 return strokes,5 initial continuous current pulses(ICCP),and 24 Mcomponents of eight triggered lightning events that occurred in the summer of 2019.The goal of the study was to explore the dynamic variation of impulse grounding resistance with lighting current injection.It was found that the impulse grounding resistances of the ICCP,M-component and return stroke were lower than that of the DC grounding resistance,while those of the ICCP and M-component superimposed on continuous current after the return stroke were slightly higher than that of the return stroke,with respective average values of 11.2Ωand 10.8Ω.Moreover,the average value of impulse grounding resistance in the M-component superimposed on the falling edge of the return stroke was 7.8Ω,which was clearly a smaller return stroke,and the minimum value reached up to 2.4Ω.The impulse grounding resistance of the ICCP and M-component decreased with the increase of lightning current,and there was no obvious correlation with the current peak of the return stroke.Finally,the impulse grounding resistance of the Mcomponent superimposed on the falling edge of the return stroke decreased exponentially with the increase of the current peak and background current value and was inversely proportional to the current peak of the return stroke.The impulse grounding resistance exhibited a dynamic change process with the injection of lightning current.After the current peak decrease of the return stroke,it increased slowly in the small current and decreased rapidly in the large current.The effects of spark and inductance differed in the varying physical processes of lightning,and both determined the ionization degree of soil,which in turn determined the magnitude and variation of the impulse grounding resistance.

关 键 词：人工触发闪电 回击 初始连续电流脉冲 M分量 冲击接地电阻 

分 类 号：P412[天文地球—大气科学及气象学]