Improvement Of Redundant Communication In Digital Substation

In recent years, with the network communication and microelectronicstechnology have dramatic growth. Digital substation is becoming the basis of thetraditional grid upgrading and reforming. Designing a redundant communication withhigh reliability, good real-time and economy will play an important role in digitalsubstation, also is a key of large-scale application.The thesis researches digital substation based on IEC61850. The basiccharacteristics of digital substation and IEC61850 are introduced, as well as relatedtopics research. According to the entire substation automation system, the thesispoints out the shortcomings and defects of the typical redundant communications, andproposes the feasible improved schemes with centralized backup pattern andcrossover backup pattern. And an economic comparison is taken for variousredundancy programs. The results show that the improved schemes can reduce theequipment investment effectively.The appropriate evaluating of redundant communications’reliability is necessaryfor its application and popularization. Therefore the thesis conducts reliabilityevaluation of redundant communication by Fault tree analysis. The assessmentindicates that the improved schemes which ameliorate the economy do not reduce itsreliability at the same, can be used in high voltage level, large-scale system of digitalsubstation communication system. And methods of reliability analysis for eachredundancy scheme have reference value in reliability analysis for redundantcommunications. Besides, the thesis analysis and calculates the important degree forcomponents in the redundancy scheme. The results show that: Although the improvedprograms reduce the number of switches, the important degree for switches are notsignificantly increased, it is not necessary to make improvement and optimization.The costs can be used to improve the reliability of the routers, servers and otherfunctions in the substation. In order to the optimal improvement in the system and theoptimal allocation of resources. It also shows that the feasibility and accuracy ofeconomic analysis that takes the same type of the switches.Redundant communication designs will determine the communication delays，and whether or not the communication delay could meet the require meets woulddirectly impact on whether functions could be performed successfully. Therefore， A simulation platform for redundant communication is built with OPNET Modeler.The results show that the improvement program is better than the existing redundantstructure in real-time. There are high prospects for application.The thesis carried out a detailed analysis and argument from the economy,reliability to real-time. The results show that the improved program havecomprehensive advantage and widespread application.