Research On Substation Network Communication And Equipment Based On IEC61850

With the swift development of substation automation, communication and microelectronic technology, many IEDs (intelligent electronic device) based on microprocessor/controller appeared in Substation Automation System. The substation automation technology improves constantly and the system integration becomes the trend. The lack of interoperability, which means that the networks and communication protocols of the IEDs may be different between different manufacturers or in different periods of the same manufacturer, has become the bottleneck problem in the development process. Therefore, the problem brings increase in cost and complexity of the system, and also affects the real-time performance and the reliability. To solve this problem and adapt to the swiftly updating computer and communication technology, IEC (International Electrotechnical Commission) formally promulgated the international standard IEC61850 about substation automation network communication in 2005. This research focuses on the NCS (networks communication in substation) based on IEC61850 and the realization of network communicator of IED according to the standard. This dissertation is divided into several parts: the system analysis of IEC61850 and the building of model; features and planning of communication networks based on IEC61850; model building of data stream of NCS and simulation of network communication; design of network communicator of IEDs according to the standard.IEC61850 is a complete and future-oriented standard of NCS and Substation Automation System. First this dissertation introduces the background, structure and main content of the standard, analyzes the connotation of information model, the technical characteristics and the modeling method. At last the two most important models, sampling message transmission model and GOOSE (Generic Object Oriented Substation Event) transmission model, are constructed and mapped to a specific communication.The physical carrier to realize IEC61850 communication is Ethernet. First this dissertation analyzes Ethernet's technique characters to acquire its communication features. Then requirements of the NCS towards circumstance, scale, safety, reliability and real-time performance are analyzed. A deep research is done on the features of network transmission delay. Based on the above research, a series of measures for the improvement of real-time performance and reliability are proposed, such as using appropriate network topology, adding priority tagging to message, adopting the node distributing program based on multi-VLAN and network redundancy method.Different from traditional Ethernet communication, NCS includes many kinds of data streams which need specific treatment. In this dissertation, the data streams of NCS based on IEC61850 are firstly analyzed and then sorted. After that, some mathematic models are built based on their features. Next, some techniques and methods of network analog are concluded, and the dynamic simulation of NCS's capability through the network analog technology based on NS-2 is conducted to get the performance standards of the relative networks. The results of the simulation prove the validity of the measures for the improvement of real-time performance and reliability, and they are benefit to the planning and building of substation network and the design of IED communicator.Beginning from the signal source of modern power system, this dissertation firstly analyzes the requirements of the digital interface of electronic transformer. Then mathematic models are built and corresponding software/hardware are designed by adopting the thought of modularization, and the communicator model of the digital interface of electronic transformer based on IEC61850 are finally realized.Moreover, in order to apply it to other IEDs' network communication and acquire extensive use and compatibility, the proto type is extended and modified. Finally through the test in designed circumstance, the dissertation proves that the model's communication capability meets the requirements and has high reliability.