季节性冻土地区牵引变电所接地方案研究

在季节性冻土地区,地面冻土层的土壤电阻率随季节性因素变化很大,将严重影响接地网的安全性能,此时采用参数合适的复合接地网将比水平接地网具有更好的降阻效果及安全性能。以哈牡铁路亚沟牵引变电所为例,采用CDEGS软件进行仿真计算的方法,分析在季节性冻土地区影响接地网安全性能的四个因素(水平均压带网格大小;垂直接地极数量、长度及位置),得出采用水平均压带与垂直接地极相结合的复合接地网方案为工程最佳方案。

Study on Grounding Scheme of Traction Substation in Seasonal Frozen Soil Area

In seasonal frozen soil area,the soil resistivity of the freezing layer varies greatly with season,which seriously affects the safety performance of the grounding grid. Compared with the horizontal grounding grid,the composite grounding gird with proper parameters has much better network resistance reduction effect and security performance. With reference to the traction substation of Ya-gou on Harbin-Mudanjiang Railway and based on CDEGS software simulation,this paper analyzes the influences of such four factors as horizontal grid size; number,length and position of vertical grounding electrode on grounding grid safety performance. The results show that composite grounding grid of horizontal uniform pressure zone with vertical earthing electrode is the optimal engineering scheme.