The lightning protection performance of transmission lines in frozen soil areas is closely related to soil electrical parameters.Existing studies mostly focus on room temperature soils, and there is a lack of experimental analysis of the frequency-dependent characteristics of permafrost electrical parameters.In this paper, the frequency changes of resistivity and relative dielectric constant in the range of 100 Hz~10 MHz of soil with an initial moisture content of 12% were measured at different temperatures.The results showed that the decrease of soil temperature led to a significant increase in resistivity and a decrease in relative dielectric constant.Under negative temperature conditions, water freezes into ice, and the dielectric constant is much smaller than that of liquid water, which makes the difference between frozen soil and room temperature soil significant.With the increase of frequency, the soil dielectric constant tends to be stable, and the polarization effect weakens at high frequency.The results reveal the frequency-dependent characteristics of the electrical parameters of permafrost, which provides an experimental basis for further research on the broadband response of permafrost grounding devices.

frozen soil; resistivity; relative dielectric constant