复合绝缘子憎水特性与其微观特性的对应关系

Relationship Between Hydrophobic Properties and Micro Characteristics of Composite Insulators

为研究复合绝缘子憎水特性与其微观特性的对应关系,选取江西电网4串线路复合绝缘子进行憎水性及憎水性迁移试验,采用傅里叶变换红外光谱(FTIR)、X射线光电子能谱(XPS)以及X射线衍射(XRD)等微观分析技术,研究了绝缘子表面元素含量及化合态以及微观结构变化情况。研究发现,表面粉化严重的绝缘子保持较高的静态接触角,与其粉化后表面粗糙度上升密切相关;静态接触角不能作为评估粗糙表面憎水性的唯一依据,应结合绝缘子表面是否保持有足够含量的憎水性基团进行评估。复合绝缘子憎水迁移性能优劣与其表层是否存在硅氧烷XRD衍射峰具有良好的对应关系,建议测量复合绝缘子表层是否存在硅氧烷XRD衍射峰,判断其憎水迁移性能否满足继续运行要求。

To study the relationship between hydrophobicity properties and micro characteristics of composite insulators,four composite insulators operated in Jiangxi power grid were randomly selected for hydrophobicity and hydrophobicity migration tests.Fourier transform infrared spectroscopy(FTIR),X-ray photoelectron spectroscopy(XPS)and X-ray diffraction(XRD)were adopted to analyze the changes of element content,chemical state,and microstructure.Results show that,due to the increase of surface roughness,serious chalking insulator commonly possesses a big static contact angle.Thus,the static contact angle cannot be used as a sole criterion for evaluating hydrophobicity of a rough surface.Nevertheless,it should be evaluated by the combination of whether there are sufficient hydrophobic groups in the surface.Whether the hydrophobicity migration performance of a composite insulator is high or not is quite consistent with whether there is asiloxane XRD diffraction peak in the surface layer.It is suggested that to detect siloxane XRD peak in the surface layer is a possible method to determine whether the hydrophobicity transfer performance can meet the requirements of continuous operation.