Reliability Research Of Intelligent Substation Protection System Based On Reliability Block Diagram Method

Smart substation is the key point and innovation point of smart power grid construction,while relay protection technology is the core of safety,efficiency and stability of power system.In the relay protection system of intelligent substation is the original independent relay protection device of functional decomposition into different ieds to factors affecting the reliability of the intelligent substation relay protection is more and more diversified and complicated,which makes the intelligent substation relay protection system in such aspects as system structure and components than traditional substation has very big difference.How to discuss the reliability of the intelligent substation relay protection system,and evaluation,combined with the evaluation results found that the defects of relay protection system and correct them,to improve the veracity and reliability of protection action,has great practical significance.The article first has carried on the simple structure of intelligent substation definition and description,on this basis,this paper introduces the intelligent substation relay protection system structure and main components,and then explains the reliability,calculated kinds of single set of protection reliability of the network mode,and compared with the traditional protection reliability;And then taking the 220 k V Haiming substation from Jianyang district power grid as a prototype,the reliability block diagram method is used to build the intelligent substation protection system reliability model,and using the algorithm of shortest path set and minimization algorithm,a 220 k V in great area power grid intelligent substation main transformer protection,220 k V line protection,bus coupler protection,110 k V line protection,and the reliability of busbar protection has carried on the computation and simulation.The results show that the main transformer protection,220 k V line protection,parent protection,110 k V line protection and the reliability of bus protection can meet the requirements.With the GO method and flow method then verified the results of reliability block diagram method,and has carried on the comparative analysis to the actual operation data,it is concluded that the reliability block diagram method is superior to other two methods.Finally,based on the network structure of the optimized protection system,this paper proposes the use of ring network structure to replace the existing network structure,and constructs the reliability block diagram of new bus protection.By calculation,the reliability of bus protection is improved obviously after optimization.For soft backup plan and share abackup plan is analyzed and calculated,and in view of the network,increase chicago-brewed GOOSE message processing element is presented,using the virtual local area network technology and can improve the reliability of relay protection network.