Assessment Strategy for Inner Insulation Condition of Power Transformer Based on Set-pair Analysis and Evidential Reasoning Decision-making
Liao Ruiji · Gao dianya jishu · 2014
Faults of power transformers have complex mechanisms, so there are various uncertain factors that could reflect the condition of inner insulation in transformers. Therefore, on the basis of practical engineering experiences, we proposed an assessment index system, as well as an integrated model based on set-pair analysis and evidential reasoning reconciling for assessing transformer inner insulation. The integrated model is composed of two levels: the first level adopts a set-pair analysis model to deal with data uncertainty and to generate basic probability assignments for the second level; the second level utilizes an evidential reasoning decision-making model to reconcile all the evidences and to calculate their membership degrees, and eventually to give an conclusive evaluation of insulation according to the maximum membership degree and confidence criteria. The model is preliminarily verified by assessment of a practical case, which means it can be an effective method for future insulation evaluation and maintenance projecting of power transformers.