Insulation State Assessment of Cable Intermediate Joint based on the Combination of Variable Weight and TOPSIS

In order to understand the insulation operation state of cable joint in real time, an evaluation method of cable joint insulation state based on improved TOPSIS with variable weight is proposed. Taking the partial discharge(PD) data monitored online as an example, the representative PD characteristic parameters is selected. Furthermore, Sen + Mann-Kendall test method is used to quantitatively calculate the trend change of corresponding PD characteristic parameters. Then the deterioration degree is introduced to normalize the PD characteristic parameters. Considering the change of weight under extreme deterioration, a variable weight function is constructed to optimize the constant weight. Finally, an improved TOPSIS method is applied to construct the cable intermediate joint state evaluation model. The case analysis shows that this model is more accurately than the traditional model in assessing the insulation condition of cable intermediate joint.