直流电流下土壤电阻率的变化规律及仿真研究

Variation and simulation of soil resistivity under DC current

研究了土壤含水量、电流密度以及长时间电流作用对电阻率的影响。通过试验研究可知,土壤含水量越高电阻率越低,同时直流下电阻率最大值对应的电流密度也越高;土壤电阻率随电流密度呈现先增大后减小的趋势,河沙随电流密度增大而增大;在有限元仿真软件中,基于试验结果建模计算得到了直流电流下土壤电阻率与电流密度的函数,验证了电阻率非线性特性模型应用于接地参数计算中的可行性。

Understanding the nonlinear characteristics of soil resistivity under current with high density will help to accurately analyze the safety performance of grounding devices in actual working conditions. The effects of soil water content, current density and long time current on resistivity were studied in this paper. According to the experimental study, it was found that the higher the water content is, the lower the soil resistivity is;and the current density corresponding to the maximum resistivity is also higher under DC. The resistivity of soil increased first and then decreased with the current density, while the river sand increases with the current density. Using the finite element simulation software, the function of soil resistivity and electric current density under direct current was calculated based on the experiment results, and the feasibility of applying the nonlinear resistivity model to the calculation of grounding parameters was verified.