Insulation State Assessment of Cable Intermediate Joint based on Fuzzy Comprehensive Evaluation with Variable Weight

Based on the close relationship between partial discharge(PD) and cable immediate joint insulation, a method based on variable weight and fuzzy comprehensive evaluation is proposed, and the cable joint insulation evaluation model is established. Firstly, this model selects the representative PD characteristic parameters as the quantitative index of cable joint insulation state, and uses the analytic hierarchy process to determine the constant weight of each index. Considering the imbalance of indicators, the variable weight theory is introduced to optimize the constant weight. Furthermore, the ridge membership function of PD parameters corresponding to different state levels is established. Finally, the insulation state evaluation of cable intermediate joints is realized based on the fuzzy comprehensive evaluation method. The case analysis shows that the variable weights can better reflect the data characteristics of the indexes. Therefore, the variable weight fuzzy comprehensive evaluation method can more accurately and effectively evaluate the insulation status of cable intermediate joints.