表面生长微生物对电气设备外绝缘性能的影响

Effects of Surface Grown Microorganisms on External Insulation Performance of Electrical Equipment

电力设备长期处于潮湿环境下,表面容易滋长霉菌、青苔等微生物,影响电气设备外绝缘的电气性能和使用寿命。本文介绍了微生物的生长机理,通过憎水性试验,研究了绿藻对复合绝缘子憎水性的影响,研究结果表明:有绿藻生长的硅橡胶伞裙完全丧失了憎水性,其静态接触角在20°左右,表现出很强的亲水性,而新伞裙和污秽伞裙的静态接触角均在90°以上,均表现为憎水性。同时通过对玻璃绝缘子进行污闪试验,研究了玻璃绝缘子表面生长苔藓对绝缘子闪络特性的影响,研究结果表明:有苔藓生长的玻璃绝缘子的单片污闪电压为43.1 kV,其电气特性符合线路运行要求。然而,生长苔藓部位的绝缘子的盐密和灰密值明显大于没有生长苔藓的绝缘子区域,运行一段时间后,势必会降低绝缘子的电气性能,给绝缘子的安全稳定运行造成隐患。最后给出了防治微生物生长的措施。

Electric power equipment has been in humid environment for a long time, the surface is easy to grow fungi, moss and other microorganisms, endangering the electrical performance and service life of external insulation of electrical equipment. The growth mechanism of microorganisms is introduced, and the effect of green algae on the hydrophobicity of composite insulators is studied through hydrophobicity test. The results show that silicone rubber umbrella skirt by green algae lost its hydrophobicity completely, and its static contact angle is about 20°, showing strong hydrophilicity, while the static contact angle of new umbrella skirt and dirty umbrella skirt are above 90°, showing hydrophobicity. At the same time, the influence of moss on the flashover characteristics of glass insulators is studied through pollution flashover test. The results show that the single pollution flashover voltage of moss-grown glass insulators is 43.1 kV, and its electrical characteristics still meet the requirements of line operation. However, due to the fact that the salt andash densities of moss growing parts of glass insulators are significantly higher than those of non-moss growing parts, with the passage of time, the salt and ash densities of moss parts will further increase, which will cause hidden dangers to the safe operation of insulators. Therefore,attention should be paid to and regular cleaning should be carried out. Finally, measures to prevent and control microbial growth are given.