Research For Several Key Technologies Of Distribution Network Substation Wide Area Protection Based On Network Topology

With the continuous development of society, the progress of scienceand technology and the rising living standards of people’s life,people’sdemand of power has increased more and more highly.In order to makethe power system more strongly,the concept of wide-area protection wasput out.Different with the traditional unit protection, which only useslocal measured information as its operation basis, the wide area protectiondraws support from today’s developed communication and computertechnology to share all the relevant electrical data and information andthen make area protection and control decision according to power net’sfault or abnormal status. This paper introduces some concepts and mainideas of wide area protection.The paper discusses some application schemes of wide area backupprotection based on grid computing, including online partition ofprotection zones, and algorithm of back-up protection. The wide areabackup protection attains information of protections’ and breakers’operation status from grid platform, and achieves optimized fault cutting decision by reasoning process of intelligent devices. The paper introducesa back-up protection expert system based on action factors. By simulation,the superiority of the algorithm is proved.Besides, this paper introduces a way to build the matrix of the digitalsubstation relay protection. That is, to combine the classic protectionprinciple with the programmable logic and make them as a “BlackBox”.To enable logic part to be digital, this paper mainly discuss how toform a "black box" which in the form of matrix, and to design the methodto form the matrix which in the angle of the mathematical mothod, anduse MATLAB to simulate and verify.