Abstract: The seasonal change will change the soil resistivity value, and the change of soil resistivity will have an impact on the impedance value of the grounding device. On the basis of soil resistivity monitoring of a certain region, the impedance changes of different types of grounding earthing devices buried in this field area are studied. The results show that the correlation analysis, throughout the year soil resistivity and temperature changes in the region are strongly negatively correlated, showing obvious seasonal changes in characteristics. When designing regional grounding network greatly affected by seasonal change,the methods can be used increasing the area of the ground network, ground network depth and the use of small permeability, good flexibility of the graphite grounding device to reduce the seasonal changes in the value of the impact of the grounding impedance,to provide reference for the design of grounding grids in areas greatly affected by seasonal changes.

Key words: seasonal variation, soil resistivity, grounding impedance