Fault Diagnosis For Power Transmission And Transformation Equipments Based On Internet Of Things

Transmission and Transformation equipment is very important for power grid,and some fault happens on it, it will influence safe and reliable operation of the powersystem. So, necessary check and diagnosis for transmission and transformationequipment are executed. At present, the condition based maintenance is fully carriedout in the company of power grid, and much progress is made in fault diagnosis, butthe accuracy and real–time of diagnosis can not be guaranteed.In this thesis, internet of things (IoT) is introduced into the fault diagnosis. Onone hand, it can improve the realtime of diagnosis; on the other hand, it can providemuch and comprehensive status information of transmission and transformationequipment for fault diagnosis, which will be processed by using the technology ofinfoemation fusion, which can integrate the information from different aspects, andcan cognaize and describe the equipment diagnosised more precise and fully. So, theaccuracy can be impoved.At the beginning of the thesis, on the basis of different definition synthesized,the concept of IoT oriented smart grid is proposed. According to the feature of keytechnologies related with IoT, their application in power system is discussed. Futhermore, the advantages of introducing IoT into fault diagnosis are probed, and accordingto the characteristic of IoT and the architecture oriented smart grid, the IoT-basedarchitecture of fault diagnosis for transmission and transformation equipment isdivided into three layers: sensing layer, communication layer and application layer.The sensing layer and application layer are concerned with accuracy of diagnosis, andthe communication layer provides convenience for real-time diagnosis.Then, on the basis of the summarized information source, including on-linemonitoring information, operational information, routine electrical tests informationand history infroamtion, the technology of information fusion is introduced in order torealize intelligent process of the information from IoT. The advantages of introducinginformation fusion into fault diagnosis for transmission and transformation equipmentare discussed, and according to the methods, levels and steps of information fusion, amulti-layer information fusion model is build.Next, combined with on-line monitoring information and patrol information, andon the basis of comparing the merit shortcoming of the information fusion methods, a integrated information fusion method based on fuzzy theory and evidence theory isproposed.and muli-source information acquired by internet of things should beprocessed. In the partial fuion based on fuzzy theory, the formation of membershipfuction and fuzzy relation matrix are emphatically discussed; in the dicision fusionbased on evidence theory, the steps and the principles of judgment of dicision fusionare represented.Finally, with the help of an instance analysis of power transformer, it is provedthat the diagnosis result obtained by multi-source information fusiuon is moreaccurate than the result by using single-source information.