Research on maintenance method of relay protection state based on combination weight and gray relation

Relatively independent evaluation parameters are selected from many through pedigree clustering.Learning the analytic hierarchy process (ahp) and entropy weight method can determine weight, at same time to understand error of is large, so combination subjective objective obtained by two methods, using improved weight-ahp weight. The calculation has a clear hierarchical structure, which not only considers influence factors, but also makes full use information in structure. Considering uncertainty information, gray relation adopted deal with data, as make maintenance rules.