接地极对矩形接地网的降阻效果研究

The Effect of Earthing Poles on Reducing Resistance of Rectangular Grounding Grid

接地技术中,在矩形接地网四周顶点敷设接地极是比较常见的优化接地网接地性能的措施。笔者研究了在面积相同的矩形接地网边缘四顶点敷设接地极对接地网的降阻效果,通过改变接地极敷设角度、接地极长度以及分层土壤结构探究接地极对不同长宽比矩形接地网的降阻效果,最后将确定的最佳的敷设方案与常见的垂直敷设方案进行对比。结果表明:按一定角度倾斜敷设接地极对矩形接地网的降阻率可达18%以上;接地极长为1~1.3倍接地网等效半径时降阻效率最高,其单位长度降阻率可达18.5%;对比接地极垂直敷设方案,将接地极倾斜敷设方案的降阻率在4.3%左右,效果不明显;当土壤非均匀时,通过倾斜敷设接地极,增大与低电阻率土壤区的接触面积,可以提高降阻效果。

In the grounding technology,laying earthing poles at the apex around the rectangular grounding grid is a common measure to optimize the grounding performance of the grounding grid.The author studies the resistance reduction effect of laying earthing poles at the four vertices of the edge of the rectangular grounding grid with the same area on the grounding grid,exploring the resistance reduction effect of the earthing poles on rectangular grounding grids with different aspect ratios by changing the laying angle of theearthing poles,the length of the earthing poles and the layered soil structure.Finally,comparing the determined optimal laying plan with the common vertical laying plan.The results reveal that:he resistance reduction rate of the rectangular grounding grid by obliquely laying the earthing poles at a certain angle is above 18%;when the earthing pole length is 1~1.3 times the equivalent radius of the grounding grid,the resistance reduction efficiency is the highest,and the resistance reduction rate per unit length can reach 18.5%;compared with the vertical installation of the earthing pole,the resistance reduction rate of the inclined installation of the earthing pole is about 4.3%,and the effect is not obvious;when the soil is non-uniform,the earthing pole is laid obliquely to increase the contact area with the low-resistivity soil area.The resistance reduction effect will be better.