Design and Research of UHVDC Earth Electrode Based on CDEGS Calculation

Based on the measured soil resistivity of the ground pole of Longdong converter station, CDEGS software was used to build a simulation model of the earth Electrode. we calculate the earthing resistance, step potential difference, touch potential difference, current releasing density and other parameters, then analyze the feasibility of the pole ring design scheme. The results show that the maximum step potential difference is the main control condition of the dimension of the earth electrode. In order to reduce the housing demolition, the maximum step potential difference is controlled within the limit value by increasing the buried depth of the earth electrode, increasing the size of the feeding rod and the cross section of the carbon coke.The design scheme of the pole ring is further optimized.