Study On Lightning Protection And Grounding Problems Of Zhanjiang 220 KV Wentao Substation Extension Project

For the safe operation of substations,lightning-proof grounding system plays a great role.When faults happen on the equipment of the power system,the lightning-proof grounding system will start.The fault current quickly leaks into the earth,and at the same time,the ground potential is lowered below the safety value of step voltage and contact voltage of human body,and the equipment will not be counterattacked secondly,so as to ensure the reliable safety of equipment and human body.Therefore,in the substation expansion project,it is necessary to design lightning protection and grounding.Based on the common problems of lightning protection grounding system to be solved,such as equipment grounding,soil resistivity,grounding resistance and so on,this paper studies several methods of reducing grounding resistance combined with existing grounding technology and new grounding materials,and then designs and calculates the grounding grid of substation according to practical experience in work.The grounding resistance and grounding resistance of underwater grounding grid are estimated and analyzed.The extension project of Wentao 220 kV substation in Zhanjiang is combined with the design and transformation of grounding grid.The design and transformation scheme are made according to local conditions.Through the analysis of the results after the completion of implementation,the grounding resistance,contact voltage and step voltage all comply with the standards.