Application Research On CDEGS Software In Design Of UHV Substation Grounding

The substation grounding system is the fundamental guarantee and important facility for maintaining the safe and reliable operation of the power system and ensuring the safety of power equipments and operating personals.With the emergence of large-capacity and long-distance EHV and UHV power grids,the grounding short-circuit current of the power system has been increased greatly,and the ground potential rise of the substation grounding grid is getting higher and higher,which puts forward more stringent requirements for substation grounding system to protect human beings,primary equipment and electronic monitoring devices with low anti-interference ability.Therefore,the study on the safety performance of grounding system is of great significance to ensure the safe and stable operation of substation.The main grounding network optimization design of transformer substation of vital significance to the safe and stable operation,the key point of UHV substation design field of research.,on the basis of considering the soil layer resistivity,optimize the structure of the grounding network is a key core UHV substation grounding design,grounding network design optimization study is to improve the safety and reliability of the power system operation,and has important theoretical significance.In this paper,by analyzing the soil inhomogeneity and docking the influence of the performance,optimization analysis determine the structure and layout of grounding network,determine the most reasonable in technical and economic design of 1000 kv substation grounding system.Use of soil resistivity according to the measured values,the application Canada CDEGS substation grounding on the main grounding network simulation program.First,the functional description of CDEGS software was described in the paper,and the content of the basic theory for substation grounding system are discussed.Next,in order to do the guarantee personal safety,limit step and touch voltages within the human body safety value,improve the level of network security,the paper on uhv substation soil structure model and its influence factors are analyzed,focusing on uhv substation soil structure model,the shunt coefficient,net model,step and touch voltages housings,insulation floor’s influence on the safety limit,grounding resistance and ground potential rise and the GIS grounding scheme,this paper analyzed the related content and assessments.Finally,through the establishment of layered soil resistivity model and the current model,the main grounding network model,and according to the design code requirements,soil resistivity according to the measured values,application Canada CDEGS substation grounding program was carried out on the main grounding network simulation software,verify the validity of the theoretical research.