The Research Of Substation Process Level And Bay Level Technique Based On IEC 61850

With the application of electronic transformers and optical fiber technique in substation, and the implementation of IEC 61850 standard, digital substation has became the development trend of substation automation system. Compared with the routine substation, the secondary system's structure of digital substation is completely digitized, which possesses the uniform data model in whole substation and data communication platform, so that the secondary system of substation is deeply changed, which brings a series of new technical issues. Considering the application request of relay protection in digital substation, the thesis carries out research mostly on the technique of process level and bay level.Firstly, the present situation of research and application about digital substation is analyzed and summarized in the thesis, on this basis, the IEC 61850 standard has been construed, in which sampled value model, GOOSE transfer model and their specific communication service mapping are discussed in detail, These provide the basis for the devices design of process level and bay level.In digital substation, the merging unit is the most important device in process level. On the basis of merging unit's functional requirements analysis, a hardware design scheme of MU is put forward in the thesis, which is consist of FPGA, DSP, ARM chips and possesses multitask operation ability. the basic hardware structure and core module function configuration of MU are described here, and the software preliminary plan of MU is briefly showed too.The intelligent device for relay protection occupies an important position in bay level. a design scheme suited for overcurrent protection in digital substation is submitted, in which three stage protection is taken as an example. The thesis has introduced the fundamental function and characteristic of each key plug-in in protection units, then systematic described the basic principles, main algorithm, and software flow of overcurrent protection.A key issue about the application of IEC 61850 is how to establish the information models from real IEDs according to the standard. Taken MU and protection unit as an example, the method for how to establish abstract information model is studied, which is constructed by logical device, logical note, data object and data attribute, in order to implement the communication among process level and bay level IEDs, bay level IEDs and substation level's computers.Finally, the subject has been summarized, and what should be done next has been prospected.