【摘要】 基于复合绝缘子的转轮法对绝缘胶(SR)绝缘子在不同时效下的老化行为进行了试验研究，通过在2 000 h内每200 h进行一次采样，对绝缘子用硅橡胶的热性能、机械性能、电气性能进行不同时限下的比较，同时以热重分析(TGA)、扫描电子显微镜(SEM)对其内部结构分析，最后采用能量色散X射线散射(EDX)分析其老化时间对绝缘子硅橡胶的元素组成比、峰面积和硬度的影响。测试结果表明能够恢复绝缘子疏水性的小尺寸低分子量分子(SLMW)几乎占总低分子量分子(LMW)的15%。在长达2 000 h的试验后，提供疏水性的聚二甲基硅氧烷(PDMS)聚合物热稳定性能下降了10%左右，绝缘子的表面硬度增加20%左右。通过ATR-FTIR的分析结果可知，Si-O-Si峰的下降速率高于vSi-C与vOH的峰，下降了50%。与原始试样相比，试验后绝缘子试样的拉伸强度和断裂应变平均降低了30%和25%。随着试验时间的增加，泄漏电流从50μA增加到500μA,但仍低于1 mA,因此没有临界退化现象产生。本试验研究可为复合绝缘子的老化性能分析提供一定的试验指导。更多还原

【Abstract】 The aging behavior of insulating rubber(SR) insulators under different aging conditions was experimentally studied based on the wheel method of composite insulators. Through sampling every 200 h within 2 000 h, the thermal, mechanical, electrical and ART-IR properties of silicone rubber used for insulators were compared under different time limits. At the same time, thermogravimetric analysis(TGA) and scanning electron microscopy(SEM) were adopted to analyze its internal structure. Finally, energy dispersive X-ray scattering(EDX) was used to analyze the effect of aging time on the element composition ratio, peak area and hardness of insulator silicone rubber. The test results show that the small size low molecular weight molecules(SLMW) that can restore the hydrophobicity of insulators account for almost 15% of the total low molecular weight molecules(LMW). After 2000h of testing, the thermal stability of the polydimethylsiloxane(PDMS) polymer, which provides hydrophobicity, decreased by about 10%, and the surface hardness of the insulator increased by about 20%. According to ATR-FTIR analysis results, the decline rate of SI-O-SI peak was 50% lower than that of VSI-C and vOH peak. Compared with the original samples, the tensile strength and fracture strain of the insulator samples decreased by 30% and 25% on average after the test. As the test time increases, the leakage current increases from 50 μa to 500 μa, but is still below 1 mA, so there is no critical degradation phenomenon. This study can provide some experimental guidance for the aging performance analysis of composite insulators.更多还原