高电压技术2018,Vol.44Issue(5):1490-1498,9.DOI:10.13336/j.1003-6520.hve.20180430013
地表垂直落差对接地网接地电阻测量的影响及改善措施
Influence of Vertical Drop of Soil on Grounding Resistance Measurement of Grounding Grid and the Improvement Measures
摘要
Abstract
The environment of hydropower station mainly consists of mountain and river, thus the soil structure of this topography is complex as well as an obvious vertical drop. Therefore, the position of measuring electrode has a significant effect on the measurement results when measuring the grounding resistance of the grounding grid. On the basis of the traditional vertical three-layer soil structure model, taking the vertical drop between the water and the bank into account, we build a soil structure model which is more consistent with the actual situation. Based on this soil model, the grounding resistance calculation and the distribution of surface potential when current is injected are calculated, and the influence of measurement electrode layout position on the resistance measurement is analyzed when using the rules method, and the correction method of compensation point position is analyzed, discussed, and put forward. The analysis results show that the potential of the soil near river is distorted when there is an obvious vertical drop in the surface layer. By using the rules method to measure grounding resistance and wiring along the river, the distortion of measurement result of ground resistance and compensation point position is serious when the horizontal distance between the electrode and the river is less than 50 m, and the measured results tend to be stable with the increase of the distance. In this case, the compensation point is closer to the ground grid than the '0.618', and its value decreases with the increase of the soil resistivity reflection coefficient. The results of this paper can provide reference for grounding resistance measurement of grounding grid in complex soil structures.关键词
水电站/接地电阻/垂直落差/落差土壤结构/补偿点/电极位置Key words
hydropower station/grounding resistance/vertical drop/soil with vertical drop/compensation point/position of electrode引用本文复制引用
司马文霞,罗东辉,袁涛,刘三伟,彭庆军,周仿荣..地表垂直落差对接地网接地电阻测量的影响及改善措施[J].高电压技术,2018,44(5):1490-1498,9.基金项目
国家自然科学基金 (51107153).Project supported by National Natural Science Foundation of China (51107153). (51107153)