757 / 2022-03-31 21:05:35

Comprehensive Evaluation Method for Latent Defects of Basin Insulator in GIS

GIS basin insulator,Latent defects,Comprehensive evaluation method,Defects

Purpose/Aim

Basin insulator is the weakest insulation link in GIS, and its insulation performance largely depends on whether there are defects on the surface and interior of the basin and the surface of metal electrode. During the production, test, installation and operation of basin insulator, it is very easy to introduce latent defects such as gas gap, surface bulge or depression, conductive particles and so on for various reasons. These defects will cause sudden changes in the electric field near it, resulting in GIS equipment failure and affecting the stable operation of power system. The aim of this paper is to present a comprehensive evaluation method for latent defects of basin insulator in GIS.

Experimental/Modeling methods

The latent defects of GIS are screened by partial discharge detection, and the size and location of defects are further determined by X-ray detection. Based on the influence of various latent defects on GIS insulation deterioration, a comprehensive evaluation function is constructed, the harm degree of various defects is quantified, and the comprehensive evaluation and early warning identification of GIS latent defects are realized.

Results/discussion

Using the comprehensive evaluation method proposed in this paper, taking a 252kV GIS bus support insulator as the object, combined with its X-ray detection results, the harm degree of its latent defects is evaluated, and it is suggested to arrange power outage maintenance as soon as possible. The withstand voltage test verifies the effectiveness of the evaluation results of the method proposed in this paper.

Conclusions

The comprehensive evaluation method proposed in this paper considers the influence law of insulation defects such as air gap and micro crack on its flashover characteristics, and can comprehensively evaluate the harm degree of latent defects of GIS insulation. It is verified by an example that it has good engineering application value.