Analysis of grounding impedance spectrum based on CDEGS with different soil characteristics

With the continuous expansion of power system capacity, transmission line tower grounding has become a more significant research object. The design of grounding device is directly related to the safe and stable operation of power system. If the design is unreasonable, it may cause personal accidents and damage to system equipment. Due to the complex structure of grounding system, the single frequency analysis can't meet the requirements of grounding application, so it is necessary to conduct multi-dimensional frequency analysis in combination with spectrum analysis method. In the grounding system, the important index of grounding resistance is affected by many factors, the most serious is the soil characteristics, such as soil resistivity, relative permeability and relative dielectric coefficient. Therefore, the simulation models of three tower grounding devices are built through the HIFREQ module in CDEGS software, and the spectral impedance analysis is carried out based on different soil characteristics. It is found that the grounding impedance spectrum curve has changed greatly according to different soil characteristics, and further research is carried out.