The Applied Research Of Variable Weight Comprehensive Model On Power Transformation Condition Evaluation

The power transformer is one of the most important power transmission andtransformation equipment in the power grid, the operation reliability of thetransformer take an important act on the security and stability of power grid. In theprocess of the operation and maintenance of power transformers, the statusmaintenance repair has been accepted widely in equipment management by powerenterprises. At the same time, condition evolution is the core of the statusmaintenance of power transformer, and it will provide a good decision support for thework of status maintenance strategy making to assess a transformer accurately, thus toimprove the operational reliability of the transformer and to ensure the stable andsecure operation of the power grid.First of all, according to the classification of the common faults and preventativetest of power transformers, an analytic hierarchy process evolution system has beenbuilt in the paper, and to calculate the weights of the underlying index of evolutionsystem. Then for “Buckets effect” of the power transformer, that its extreme declineoverall safety performance only because the serious deterioration of the very fewindicators, a variable weight evolution method have been proposed in order to solvethe problem of the fixed weights evolution, and a punishment variable weight vectorfunction based on the own property of the transformer is constructed. The method ofthe variable weight improves the sensitivity of the very few serious indicators, theweight of each indicators becomes more real through redistribution. And combinedwith the membership degree of evaluation level of a single indicator by the fuzzytheory, the paper comprehensively get a condition evolution method of transformer.Finally, the accuracy and usefulness of assessment method by the variable weightis proved through two examples and comparison with fixed weights method.