Study On Optimization Design Of 500kV Substation Grounding Grid

Energy is the foundation of social operation and development.In contemporary society,electricity is one of the most important energy resources.The normal operation of the second and the third tertiary industry cannot be without reliable electricity.People can't leave electricity in their daily lives.To effectively produce,transmit and distribute electricity,reliable transmission and transmission networks are required,Under the leadership of the party,From the early days of the founding of the people's Republic of China,the construction of transmission and distribution network was vigorously constructed in our country.A backbone network spanning the north and south was built.however all kinds of substation is a node to support the network.Because of the importance of substations,safety,stability and reliability are the main considerations in the construction and operation of substation,The construction of grounding grid is the foundation of safe and stable operation of substation,The performance of the grounding grid is affected by its structure and the soil environment in which it is located.The current construction of substation grounding grids with voltage level increased.The decrease of construction area,the large soil resistivity and irregular shape lead to deterioration of grounding resistance,ground potential rise,touch voltage,step voltage and so on.This topic is based on the theory of grounding technology.The potential model of soil current source in multi-layered structure is deduced,and the important parameters that affect the performance of grounding grid are studied and analyzed according to the national standard and CDEGS software.Through the operation of software modeling,calculation,the research level of grounding grid area,with a total length of grid edge,affect the performance of grounding grounding grid level changes in the total length of the three controllable parameters,and vertical grounding grounding performance.This paper studies the method of unequal spacing arrangement by using the equal spacing of the main layout and the main compression ratio and empirical data,Analysis of the potential distribution in the corner and the central area effect of the use of software,According to the practical factors of the project and the requirements of the codes and regulations,the comprehensive advantages of the two mesh encryption scheme.The scheme was enhanced irn higher voltage level,the grounding area is larger,the operability of the horizontal grounding grid is considered when the potential distribution is uneven.The vertical grounding electrode is an important component of the grounding grid,the connection at the level of the main line,to further improve the performance of grounding grids,comprehensively improve the grounding resistance of ground potential rise,contact voltage and step voltage.Because the current shielding effect exists,The outer edge,especially the vertical grounding electrode at four angles,can play a sufficient role,studies are also concentrated in these areas.Through the study of practical engineering,analyze the problems during the operation of the project,the redundant design of vertical grounding electrode is proposed in this paper.In near the edge of the main node and the site of important equipment area,should the layout of vertical grounding,other areas should be carried out the design and construction of redundancy when conditions permit.With a limited cost increase,the reliability and durability of grounding grids are greatly improved.And the common irregular grounding grids caused by planning and other factors are studied,The selection of factors such as electrical,natural environment and planning are summarized.The final conclusion is applied to 500kV substation grounding grid project,and the inversion of soil model is carried out by software,and the method of choosing soil model is determined.In one optimization,the design scheme of network hole encryption and vertical grounding is adopted.the parameters of grounding grid have been greatly improved,and the deep well grounding and supporting scheme in the two optimization,another significant improvement in related parameters,the experimental data demonstrate the effectiveness of the research results.