110 kV复合绝缘子伞裙老化微观特征分析

Analysis of Micro Aging Characteristics of 110 kV Composite Insulator Shed

利用憎水性检测、傅里叶红外光谱及热重分析等方法对内蒙古地区某支随机抽取的110 kV复合绝缘子伞裙的微观老化特征进行分析。结果表明,除了低压侧第1片伞裙外,其他部位伞裙的老化程度基本呈线性降低趋势。低压侧第1片伞裙因常年受到光照,老化程度高于中间部位的伞裙;而高压侧第1片伞裙因离导线最近,在不均匀电场长期放电的作用下,伞裙表面Si(CH3)2和-CH3等官能团的质量分数明显减小,并且与基体相比PDMS质量分数显著降低,因而老化程度最严重。这也说明电应力因素更易对伞裙老化性能产生显著影响。建议对在役复合绝缘子的运行状况进行巡查时,可将高压侧第1片伞裙的憎水性能作为主要参考。

To study the micro aging characteristics of shed,a 110 kV composite insulator operated in Inner Mongolia area is randomly selected for hydrophobicity testing,with fourier transform infrared spectroscopy(FTIR)detection and thermogravimetric analysis(TGA)respectively.The results reveals that the aging degree of the whole composite insulator sheds are basically presented a linear decreasing trend,except for the first shed on the low voltage endside.The first shed on the low-voltage side is exposed to light all year round,and the degree of aging is higher than that of the shed in the middle part.While the first shed on the high-voltage end side is closest to the conductor,would long term suffer under the influence of long-term uneven electric field discharging due to closest to wire,causing a sharp reduction in the content mass fraction of functional groups such as Si(CH3)2 and-CH3 functional groups on the shed top surface is significantly reduced.In addition,the content mass fraction of PDMS of the shed top surface is also significantly decreased compared to with the matrix,indicating that the aging degree of the first shed on the high-voltage end side is the most serious.This explains that the electrical stress factors are more easily likely to pose a significant impact on the aging properties of composite insulator sheds.At last,it is advised recommended that the hydrophobicity of the first shed on the high-voltage end side should be taken as a main reference,when inspecting the operation property conditions of composite insulators in-serviced.