Technical and Economic Performance Analysis on Vertical Grounding Electrodes of ±800KV UHVDC

According to alternative grounding place situation of plusmn800 KV DC project, this paper selects the theoretically suitable place to design several different arrangement scenarios of vertical grounding electrodes and then compares the technical and economic performance when the sub-electrode length remains invariable while other parameters are changed and when the sub-electrode quantity remains invariable while other parameters are changed. The results show that both step voltage and grounding resistance conform to the system requests in these scenarios, but soil temperature near ground rods can not satisfy the request. Simultaneously, a series of conclusions are reached by selecting a best one of these scenarios to compare with level two-rings grounding electrode.