沿海地区复合绝缘子粉化特性研究

Research on Chalking Characteristics of Composite Insulators in Coastal Areas

复合绝缘子长期在户外运行过程中会逐渐老化,表面的硅橡胶材料会出现粉化现象影响输电线路稳定运行。为系统研究粉化后绝缘子的材料特性、微观特性以及电气特性,对粉化复合绝缘子硬度、憎水性及憎水迁移性、微观形貌以及泄漏电流进行实验研究。结果表明,粉化后的复合绝缘子表面硬度略有增加,复合绝缘子表面硬度总体趋势由高压段到低压段逐渐降低,复合绝缘子表面在同一电压段位处的护套硬度高于伞裙硬度。复合绝缘子发生粉化后憎水性和憎水迁移性均变差。复合绝缘子粉化后表面孔隙增大增多,表面粗糙度增加,附着有大量颗粒等现象。通过污耐压法研究复合绝缘子电气特性,研究发现,粉化层厚度与泄露电流无明显相关关系,尽管发生粉化,复合绝缘子电气性能依然满足运行条件。研究成果可为沿海地区粉化后复合绝缘子性能提供参考依据,对电力系统稳定运行具有一定的工程意义。

Composite insulators will gradually age during long-term outdoor operation,and the silicon rubber material on the surface will appear Chalking,which will affect the stable operation of transmission lines.In order to systematically study the material characteristics,micro characteristics and electrical characteristics of powdered composite insulators,the hardness,hydrophobicity,hydrophobic mobility,micro morphology and leakage current of powdered composite insulators were experimentally studied.The results show that the surface hardness of the composite insulator increases slightly after Chalking,the overall trend of the surface hardness of the composite insulator decreases gradually from high voltage section to low voltage section,and the sheath hardness of the composite insulator surface at the same voltage section is higher than that of the umbrella skirt.The hydrophobicity and hydrophobic mobility of composite insulators become worse after Chalking.After the composite insulator is powdered,the surface porosity increases,the surface roughness increases,and a large number of particles are attached.The electrical characteristics of composite insulators are studied by pollution withstand voltage method.It is found that there is no obvious correlation between the thickness of Chalking layer and leakage current.Despite Chalking,the electrical properties of composite insulators still meet the operating conditions.The research results can provide reference for the performance of composite insulators after pulverization in coastal areas,and have certain engineering significance for the stable operation of power system.