含人工缺陷复合绝缘子红外特征试验研究

Study on Infrared Spectra Characteristics of Composite Insulator with Artificial Defects

复合绝缘子红外图谱智能自动识别方法是未来复合绝缘子运维的重要发展方向。为获得足够的发热红外图谱样本,制作了含护套-芯棒粘接不良、芯棒-护套内部金属异物和端部金具-护套界面气隙3种人工缺陷的绝缘子。同时针对端部金具-护套界面气隙发热分析了不同空间分辨率红外镜头对红外测试结果的影响。结果表明,220 kV复合绝缘高压端芯棒-护套粘接不良缺陷仅出现轻微温升;通过不同长度金属丝异物构建的220 kV复合绝缘子高压端护套内部存在局放缺陷,温升幅值位于1.5~5.5 K;500 kV复合绝缘子高压端金具-护套界面气隙可产生7~8 K温升;对于端部金具-护套界面气隙发热,不同空间分辨率红外镜头测得温升幅值偏差平均超过20%,为保证测温精度,现场测试应选用空间分辨率更精细的红外镜头。

The automatic identification method of composite insulator infrared spectrum is an important development direction for composite insulator operation and maintenance in the future.To acquire enough infrared images of heating composite insulators are the basis for establishing such intelligent methods,three kinds of artificial defects in composite insulators such as adhesion failure between core and sheath,metal foreign body between core and sheath and interface air gap between end fitting and sheath were constructed.Also,the influence of infrared lenses with different spatial resolutions on the infrared test results is analyzed given the interface air gap between end fitting and sheath.It is indicated that there was a slight temperature rise due to adhesion failure in core and sheath at the HV terminal of the composite insulator;the temperature rise of metal foreign body with different lengths between core and sheath in 220 kV composite insulator HV end distributes in 1.5~5.5 K;the interface air gap between end fitting and sheath of 500 kV composite insulators can generate a temperature rise of 7~8 K and the deviation of its temperature rise measured by infrared lenses with different spatial resolutions exceeded by 20% on average.To ensure the accuracy of temperature measurement,an infrared lens with a finer spatial resolution should be selected for field testing.