强暴雨条件下 110 kV 硅橡胶绝缘子雷电冲击电弧发展过程与闪络特性

作者：Dong Bingbing; Song Jiale; Li Te^*; Li Jiansheng; Jiang Xingliang

来源：High Voltage Engineering, 2023, 49(2): 525-535.

DOI：10.13336/j.1003-6520.hve.20221055

• discharge characteristics
• dynamic process
• heavy rain
• lighting impulse
• SIR composite insulators

Heavy rainstorms, which are usually accompanied by lightning, can lead to an uneven distribution of the electric field in the dry and wet parts of the insulators of transmission lines, transformer substations, and converter stations, resulting in electric field distortion. Meanwhile, the rain streams caused by thunderstorms can quickly cause short-circuit between the insulator skirts and greatly shorten the flashover paths, resulting in line tripping and power failure accident. In order to study the lightning impulse discharge characteristics and arc development process of line insulators under heavy rainstorms, lightning impulse discharge characteristics of three types of silicone rubber composite insulators commonly used in 110 kV lines were tested in this paper. The results show that the development process of lightning impulse arc of composite insulator mainly includes arcing, local arc development, and complete flashover. The arc development time and the total flashover duration decrease with the increase of the rainfall intensity and rainwater conductivity. The average speed of the arc increases exponentially with the increase of rainwater conductivity, and the growth rate is as high as 43.8%. In addition, the average speed increases exponentially with the increase of rainfall intensity and depends on the structural parameters of the umbrella skirt. The lightning impulse flashover voltage exhibits a negative exponential correlation with the rainfall intensity. The flashover voltage of insulators with a large umbrella skirt spacing is more severely affected by the rainfall intensity. Furthermore, the flashover voltage decreases in a negative power exponential correlation with the increase of rainwater conductivity. Based on these results, fitting expressions for the lightning impulse flashover voltage with the combined effect of rainfall intensity and rain conductivity were proposed in this paper. The calculation results are in good agreement with the experimental results, and the errors are less than 7%. The results can serve as a reference for the design, selection, and protection of the external insulation of transmission lines in areas with frequent lightning activities and heavy rainstorms. ? 2023 Science Press.

• 单位
  合肥工业大学; 输配电装备及系统安全与新技术国家重点实验室