三峡电站模型地网接地电阻小比例模型试验研究

三峡电站所在地区的土壤深处及河床以下为高电阻率的花岗岩结构,要降低其接地电阻相当困难。文献[2]对三峡电站的模型地网进行了计算,认为在一定的技术经济条件下,将三峡电站的接地电阻降低至0．15Ω及以下是可能的。本文采用小比例模型试验方法,建立了既有水平分层又有垂直分层的试验模型,对三峡电站的模型地网的接地电阻进行了测量,并将结果与文献[2]的计算结果进行了比较,结果表明模型试验测量结果与接地计算程序的计算结果是接近的,相差不超过8％。

SMALL-SCALE MODEL TEST FOR GROUNDING RESISTANCE OF GROUNDING MESH MODEL FOR THREE GORGES HYDROELECTRIC POWER STATION

Because of the high resistivity of the deep soil at the location where the Three Gorges Hydroelectric Power Station is built and the granite structure under the river bed, it is difficult to reduce the grounding resistance in this region. In reference [2] the grounding mesh model for Three Gorges Hydroelectric Station is calculated and the conclusion is that under a certain condition of technology and economy it is possible to reduce the grounding resistance of the power station to 0.15W or lower. In this paper by use of the small-scale model method a test model with both horizontal and vertical soil layers is established with which the grounding resistance of the grounding mesh model for Three Gorges Hydroelectric Power Station is measured and the measured results are compared with the calculation results from reference [2]. The comparison results show that the measured values are close to the calculation results, the maximum difference not exceeding 8%.