Reliability Evaluation Of Secondary System Of Intelligent Substation

After Most countries have entered the era of smart grid because of the development of various technologies. As a major component of smart grid, intelligent substation integrated a large number of digital and intelligent devices and effectively improved the efficiency of operation and maintenance of the substation. However, it also increased the risk and probability of outages and blackouts due to the highly intelligentized and automatic of those substations. The reliability of secondary system of intelligent substation has been pushed to a new standard, and the corresponding evaluation algorithm and improved method also attracted wide attention.This paper focused on reliability assessment of secondary system of intelligent substations. It built the reliability evaluation indexes reference according to the characteristics and structure of secondary system of intelligent substation and indicators in other areas, which contained the component availability, system average occurs, the system is not reliable degree of probability importance and key elements of the basis for building an important. And utilized the minimum number of faults path set analysis to establish a quantitative model of these indicators, so as to establish an intelligent substation secondary system reliability evaluation model.In order to obtain results from the calculation model and to applicate in engineering practice, the paper developed a graphical simulation and analysis tool with C++ according to the characteristics and the networking model and substation secondary devices. The developed tool built visualized modules of secondary equipment on the basis of intelligent hardware modules and function modules and graphically showed their logical relationships.Based on the above research, this paper established simulation model for four common networking secondary systems of 220kV intelligent substations with the visualized tool, which are no redundancy, redundancy protection devices and combining unit, process layer cross the standby mode and redundant Ethernet mode, and then completed the reliability analysis and calculation by minimal cut set. According to the results, analysis of various groups advantages network mode and the potential problems are made in order to identify weaknesses in the secondary system, which would have some significance for design of intelligent substation secondary system, technological transformation and operations.