关键词： 变电所, 接地系统优化, 改进粒子群算法, 不等电位模型

Abstract: To solve the problem that the unequal electric potential of grounding grid can be caused by the use of steel instead of copper as a conductor.The improved PSO algorithm is used to optimize the docking system,and the optimization objective function is set up by using double layer soil and unequal potential model. The traditional particle swarm algorithm is improved through the method of fission gregarious variation to solve the problem of premature convergence and slow convergence.The simulation model was built by the actual system parameters of the grounding system of a substation. The Matlab simulation results show that compared with the equally distributed grounding system of the 80 m×60 m and 120 m×100 m substation,the unequally distributed grounding voltage according to the exponential rule by the   improved particle swarm optimization algorithm can achieve 21.65% and 23.45%. The difference of the maximum current density is 18.05% and 10.26%.It is concluded that the optimized design method of substation grounding system in this paper can effectively reduce the difference of maximum contact voltage and current density,and can effectively improve the security of the grounding system.

Key words: substation, grounding system optimization, improved particle swarm optimization algorithm, unequal potential model