The Risk Assessment Of Urban Distribution Network Based On Fuzzy Weight Theory

Urban distribution network is an important component of power transmissionand load distribution. As the basic change in the process of a majority of powertransmission and distribution system structure which is considered to be a key point,and the safety and reliability of the operation may provide high quality for users.Recently, the assessment of urban distribution network focuses on traditionalreliability and safety assessment. However, the integrality content often has beenignored. For this purpose, this thesis focuses on a study of comprehensiveassessment of the risk theory for urban distribution network.Risk theory can be viewed as a comprehensively refection of likelihood ofoccurrence and severity of consequence which causes the serious consequences ofsystem failure. With recognition of risk source, dispose of historical data and outagemodel of element, this thesis is based on the security rules of K(N-1+1) and gives afull consideration. On these grounds, this paper, in turn, builds the probability modelof failure cases, the risk model of explicit fault and implicit fault, the strength of thegrid structure risk model and the overall system risk model. According to thesequantitative assessment index can make an objective, reasonable and effectiveassessment in the partial and the whole risk of urban distribution network.In order to plan and transform the urban distribution network directly, and fullyprovide value of assets from an economic perspective, establishes the urbandistribution risk assessment system based on the factors in the process of gridoperation. Builds the integrated assessment model by the use of information entropytheory and the fuzzy comprehensive evaluation method which can respectivelymeasure the uncertainty factors and the overall system risk level effectively. Buildsthe urban distribution network economic risk evaluation model through the powercostomer interruption cost functions which makes the reflection of risk level ofurban distribution network from the economical point of view has come true. Finally, under the PSD-BPA operating environment, this thesis evaluates theurban mid-voltage distribution network of Guangming new district in a southern city.On the basis of calculation, analysis and comparison, the risk assessment modelwhich is established in this thesis is effective and reasonable, and it can plan andremould the urban mid-voltage distribution network to a certain degree.