Research On Condition Maintenance Decision Of Distribution Network Based On Risk Assessment

Distribution network is one of the important components in the power system.The safety and reliability of its operation are directly related to the power supply security and stability of the power system.The equipment operation status has always been the focus of researchers.Distribution network accidents occur most frequently in the entire power system.First,due to the relatively backward development of the distribution network,the structure is relatively simple,and the redundancy is not sufficient;on the other hand,frequent failures are also related to unscientific inspection methods.The ability to operate safely,reliably,and economically is directly related to the interests of users and power companies.Therefore,the research in this paper will focus on solving the problem of state assessment and state maintenance decision optimization for distribution network equipment,and provide a reliable reference for decision makers.First of all,this paper uses a distribution network transformer as an example to construct an operational risk assessment system,proposes two-level index factors for transformer state assessment,and establishes a multi-factor,two-level,fuzzy comprehensive assessment model for the quantitative assessment of transformer operation risks.The method of calculating the weight coefficient of the evaluation index factor and the formula of the membership function of the index factor are proposed.The disadvantages of subjective factors of weights are overcome while the fuzzy analytic hierarchy process is properly applied.Finally,the transformer operation risk quantification proposed in this paper is verified by the actual transformer case.Assess the effectiveness of the model.Secondly,according to the "Guidelines for the Evaluation of Distribution Network Equipment Status"(Q/GDW645-2011)issued in 2011,the distribution network is based on the equipment health status assessment procedure,and the failure probability health index is established based on the empirical formula of the British EA company health index.The relationship between them and the establishment of different failure rate prediction models based on different types of overhaul,correcting and improving the existing lag of failure probability,reassessing the status of equipment after repair,and introducing rehabilitation index of health age index of health index Factors,fuzzy comprehensive evaluation of the health index repair factor,make the results more persuasive;at the same time according to the actual introduction of the accident rate factor and meteorological factor to correct the fault probability model,failure probability model can comprehensively respond to aging failure,health and The influence of changes in the weather environment on the possibility of equipment failures fully considers various risk factors that affect the probability of equipment failure and is more realistic.Finally,according to the status quo of the state-of-the-art maintenance of distribution network,the analysis and solution of the maintenance benefits have not yet been clearly defined,and the method of state-based maintenance decision-making based on risk-return distribution network is proposed.From the overall level of the distribution network system,individual equipment level and external society The level defines the maintenance revenue;comprehensively considers the dialectical relationship between maintenance risk and revenue counterbalance,the requirements of the policy-makers,provides a scientific basis for reasonable maintenance,and finally validates the effectiveness of the model through examples.