Condition Assessment for Power Transformer Based on Improved Evidence Combination Rule

In view of the uncertainty transformer state information, state of transformer hierarchical evaluation model is established. Firstly, index system of transformer state is formed; Secondly, in order to get comprehensive index of state, grey clustering method is used for monomial index clustering analysis; Finally in the basis of improving synthesis rules of conflict evidence of D - S evidence theory , clustering coefficient is used as the basic probability assignment function to evaluate the overall state of transformer. Example analysis results show that the proposed evaluation model can accurately grasp the running state of transformer and provide guidance for transformer condition overhaul.