Centralized Backup Protection Algorithm Research Of Intelligent Substation

Substation protection has relay protection&back-up protection based on the function.Relay protection can remove faulty components quickly. Traditional backup protection hasshortcoming such as long delay action, tuning difficulties, prone to tripping accidents chain,so it is necessary to analyze and study for backup protection. Intelligent substation usingdigital technology and network technology can get digital standardization information andshare the information on whole station. Intelligent Substation Based on information sharing,centralized backup protection for solving the problem of traditional backup protectionprovides a new way of thinking.To solve traditional backup protection’s defects, based on Smart Substation informationsharing use the traditional primary protection plus protection configure ration centralizedbackup protection. This configuration can not only play the advantages of the traditionalprimary protection, but also makes full use of the advantages of intelligent substationinformation sharing. Once the device is configured for centralized backup substationprotection, the backup protection is optimized, helping improve protection.Study the algorithm based on the comparison of direction. According to the connectionsof the direction elements and primary equipment, to form the direction matrix is alsoimportant. Complete of the assignment matrix based on the output value of the directionalelement, Determine the threshold criterion and accurate identification of faulty components.Finally, specific examples (a device put into operation substation and substation equipmentfault identification quit running in both cases), numerical results show that the algorithm canaccurately identify the faulty component.Study the centralized backup protection algorithm based on the principle of differentialcomparator. The algorithm defines the different zones of differential (differential zoneboundary、the station of the differential area、the element of the differential area&the searchdifferential zone). Firstly, according to the different characteristics of the border area and the station differential zones, distinguish the station component failure or line failure. When theconfirmation line is fail, start the search area to determine the differential fault lines. Also,when the confirmation station component is fail, we need checking components area todetermine the fault station component. Finally, a lot of simulations using software PSCADsimulation experimental results show that the algorithm can accurately identify the faultycomponent.