Research on Damp Aging Evolution of Cables Joints Using PDC Method and Dynamic Bayes

In order to study the insulation state of the cable joint with dampness, and to accurately evaluate the dampness of the cable joint, this paper measured the time-frequency domain dielectric constant of the XLPE cable joint using the PDC (polarized depolarized current, PDC) method. And the K-means algorithm is adopted to analyze it. The classification and state interval division are carried out, and the damp process of the cable joint is divided into four stages. Then, the damp and aging insulation state evaluation model of the cable joint is established according to the dynamic Bayesian network, and the network parameters are determined to compare comprehensive judgment is made on the degree of dampness of cable joints. Finally, the 2-CV cross-validation of the proposed damp and aging evaluation model is carried out, and the accuracy rate is as high as 90.065%, which shows that the model has good resolution and effectiveness in evaluating the dampness of cable joints.