Influence of snow accretion on arc flashover gradient for various types of insulators. Issue 12 (22nd April 2020)

• Record Type: Journal Article
• Authors: Hu, Yuyao; Jiang, Xingliang; Guo, Sihua; Xian, Richang; Zong, Chunyu; Yang, Zhongyi; Han, Xingbo
• Is Part Of: IET generation, transmission & distribution. Volume 14:Issue 12(2020)
• Page Start: 2361
• Page End: 2367
• Publication Date: 2020-04-22
• Subjects: snow -- flashover -- power overhead lines -- silicone rubber insulators -- insulator contamination -- ice -- insulators; flashover tests -- snow‐accreted insulators -- AC arc flashover gradient -- nonuniform snow accumulation -- uniform snow‐covered insulator -- porcelain -- glass insulators -- silicone rubber insulator -- glass insulator -- snow thickness -- flashover process -- contaminated insulator -- iced insulator -- flashover mechanism -- snow accretion -- size 10.0 mm; Electric power production -- Periodicals; Electric power transmission -- Periodicals; Electric power distribution -- Periodicals; 621.3105
• DOI: 10.1049/iet-gtd.2020.0012
• Languages: English
• ISSNs: 1751-8687

Abstract

Abstract : Atmospheric snow accretion along the insulators can eventually bridge adjacent shed spacing, which pose severe risks to the security of power networks. Aiming to investigate the influence of snow accumulation on the electrical performance of various types of insulators, the flashover tests of snow‐accreted insulators were conducted. The effects of various factors on the electrical characteristics of insulators were analysed based on the experimental data. Results show that AC arc flashover gradient of the insulator covered with nonuniform snow accumulation is lower than that of the uniform snow‐covered insulator. The former is as low as 22.5% lower than the latter. Moreover, the AC arc flashover gradient of the porcelain and glass insulators is 0.27–6.27% higher than that of the DC. For a silicone rubber insulator, this gap is greater than 20%. The flashover gradient of the glass insulator is the minimum at the snow thickness of 10 mm. The flashover process of snow‐covered insulator is neither similar to that of the contaminated insulator nor different from that of the iced insulator but a combination of the two. The presented work helps to better understand the flashover mechanism of snow‐covered insulators, and take efforts to mitigate its effects.