基于带电检测的复合绝缘子憎水性评价

研究了复合绝缘子憎水性带电检测技术及其应用。基于喷水分级法和数字图像处理技术，提出一种改进形状因子法的憎水性等级判断方法，研制了由电动式自动喷水装置、微型数码摄像机和憎水性分析软件等组成的憎水性带电检测装置。利用所设计的装置在北方重污秽地区进行长达一年半的现场试验，发现了运行复合绝缘子憎水性的季节变化特性，并通过户外模拟试验验证了现场试验所发现规律的普遍性，从而提出了基于冬季憎水性下降特性测量和夏季憎水性恢复特性测量的运行复合绝缘子憎水性动态检测诊断新方法。应用扫描电镜技术和红外光谱分析技术，研究了运行复合绝缘子憎水性下降的原因，指出污秽在不同季节对复合绝缘子憎水性下降所造成的重要影响。最后，综合上述研究，探讨了基于憎水性带电检测的复合绝缘子运行维护方法。

Evaluation of the Hydrophobicity of Composite Insulators Based on On-line Detection

This paper introduces an on-line hydrophobicity detection technique and its application. Firstly, a new hydrophobicity classification estimation method, named improved shape factor method, was brought forward based on spray method and digital image processing technique. Also, an on-line hydrophobicity detection apparatus was designed, which includes an automatic electric sprayer, a mini digital video camera, and hydrophobicity analyzing software. Secondly, with the apparatus, field investigations on hydrophobicity of composite insulators in service were made in a heavily polluted area of north China for half and a year. A seasonal variation of hydrophobicity was found through field test, which was also confirmed by outdoor simulation test. Therefore, a new method was proposed to evaluate the dynamic performance of hydrophobicity, by online characterize hydrophobicity of the composite insulators in winter and summer, respectively. Thirdly, with SEM and ATR-FTIR techniques, the mechanism of hydrophobic decrease was analyzed, and the significant influence of pollution on hydrophobic decrease in different seasons was pointed out. Finally, the maintenance method of composite insulators based on on-line hydrophobicity detection technology was discussed.