Evaluation Model of Ternary Chemical Indicators for Aging Status of Paper Insulation at Transformer Winding Hot Spots

Existing studies have only analyzed the evaluation mechanism of chemical indicators on the ‘uniform’ aging status of paper insulation. In view of this, this work explores the use of chemical indicators to characterize the degree of aging of paper insulation hot spots. Furthermore, the ternary chemical indicators are employed as assessment factors in order to eliminate the limitations of single indicators. Determine the influence model of temperature and moisture on methanol, ethanol and furfural. Then, based on the entropy weight method, the contribution of ternary chemical indicators in the assessment of paper insulation aging is obtained. Finally, according to the distribution law of the degree of polymerization along different heights in the uneven aging state, the relationship between the degree of polymerization of the insulating paper in the hot spots area (Tmax, DPmin) and the ternary indicators in the oil could be derived.