复合绝缘子酸液侵蚀的脆断研究

Probe into Brittle Fracture of Composite Insulators Caused by Acid Erosion

在输电线路中,复合绝缘子的芯棒非联接部分频繁出现脆断、掉线,其中酸性介质侵入并渗透到内部芯棒,腐蚀芯棒截面,是造成复合绝缘子机械强度下降进而脆断的主要原因。建立了复合绝缘子的酸液侵蚀模型,利用ANASYS对其场强和电位进行仿真分析。分析结果表明,酸液侵蚀复合绝缘子后,金具处场强最大值比正常复合绝缘子数值大,且侵蚀部位场强畸变严重;复合绝缘子侵蚀后的电位分布比正常复合绝缘子的高,单片绝缘子承担的电压偏大,加速了绝缘子老化。

Composite insulators are used in a large number of transmission lines for superior electrical performance. The phenomenon of brittle fracture often appears in mandrel non-connected part leading to the occurrence of a major power outage caused by the adsorption, penetration and diffusion of acidic medium entering the internal mandrel and the mandrel cross-section. The paper establishes a composite insulator model with acid erosion, and simulates and analyzes the field strength and potential of the composite insulators by using ANASYS. The results show that maximum field strength occurred in the fittings is bigger than that in normal composite insulators, serious field distortion occurs in corroded region, the high potential distribution exists in the composite insulator with acid erosion, and single insulator with a higher voltage accelerates ageing of the insulator.