Applied Research For Distributed Bus Protection Based On Multi-Agent System In Digital Substation

The busbar protection is one of the main relay protection in the power system. Safe and reliable operation of busbar in power plants and substations directly influence the reliability of power system. Traditional centralized bus protection could not be applied in middle bus protection well. The existing distributed bus protection has made some progress in design, installation, debugging, management, etc, which reduces equipment down times. But it could not expand owing to high costs and communication technology.With enacting the IEC61850 standard and operating of digital substations, 12th Five Year Plan (2011-16) of Shanghai Power Grid will put stress on substation intelligent of grid construction, which afford good application platform for he distributed bus protection. But it's hard to making the relay protection system intellectualized. The dissertation makes research and discussion on the above questions. As the chief of the dissertation, a new distributed bus protection scheme using the distributed hierarchical control methodologies based on multi-agent system (MAS) theory, which has got many achievements with respect to distributed artificial intelligence and distributed control, is proposed and investigated systematically. The scheme meets the requirement of combining physical integration to logic integration for protection control system in intelligent substation.This dissertation analyzed various existing distributed bus protection schemes, combined the new request of relay protection control system in substation, and studied the object-oriented technology and object models that used in IEC61850. The hierarchical control methodologies based on multi-agent system theory is applied in intellectualized substation. Depending on the logical devices and logical node of IEC61850, LN-based MAS distributed hierarchical control system is presented.Combining direction atresia busbar protection principle,the structure, functions, characteristics and implement technical scheme of the distributed bus protection based on MAS are discussed in detail. Distributed bus protection technique is be incorporated into artificial intelligence control technology, and solves digital substation of low-voltage busbar protection existing problems successfully, which constitutes protection control system initial "intelligence" pattern in substation. At the end of the dissertation, according to the 12th Five Year Plan of Shanghai Power Grid, the conditions to realize protection scheme are analyzed. Then the feasibility of implementation of the protection scheme in Shanghai grid is discussed. The research work of MAS technology used in intelligent power grid is prospected. The further work is pointed out as well.