Theory Study And System Development Of Relay Settings Verification Based On EMS Real-time Information

With the rapid development of grid construction, the topological structure and operation mode of large scale interconnected power system are becoming much more complex and variable, which makes the disadvantages of traditional off-line relay settings calculation mode increasingly serious. In order to prevent relay protections from incorrect operation and ensure the security of power system, it is critical important to research on how to fully utilize EMS real-time information of power system to verify the senility and selectivity of relay settings on-line.In this paper, a relay settings verification system based on EMS real-time information will be approached. The main contents are as follows:Firstly, the research background and status of relay settings verification system based on EMS real-time information are summarized. Then a weighted undirected spectral graph partitioning approach is proposed for the grouping of relay protections. In this approach, the relays grouping problem is converted to a weighted undirected graph partitioning problem after its characteristic analysis, and a mathematic model is formulated. On this basis, an improved approach based on boundary nod moving is put forward. The simulation on Hubei 500kV power system demonstrates that the improved partitioning approach can group the relay protections in a reasonably way.Secondly, the overall structure, database design and entire implementing process of relay on-line verification system are expounded. Then some key problems are solved, including intelligent EMS real-time information processing, fast verification principles for three-step grounding distance protection, partial verification mode and parallel computation.Thirdly, with the extensive application of new equipments and technology such as digital substation technology, WAMS (Wide Area Measurement System), WACS (Wide Area Control System) .etc, recent development of relay protection in smart grid environment is discussed. Then the application background and example of state grid standardized relay protection are introduced. In addition, the status and prospects of research on relay settings on-line calculation system based on wide area communication are expounded, and its typical structure is put forward. At last, the conception of relay settings intelligent on-line calculation and integrated management is proposed.