瓷绝缘子在配电线路中应用广泛, 受长期机电应力与户外恶劣环境影响, 在运行中易发生劣化。红外热像法是一种重要的劣化绝缘子带电检测方法, 具有检测方便、安全高效和非接触式的优点, 已成为线路巡检的重要手段, 但劣化绝缘子热像特征不明显, 肉眼识别易出现误判。为此, 本文首先对配电线路瓷绝缘子进行温度场仿真分析, 然后提出了一种劣化绝缘子红外热像检测方法, 采用多尺度模板匹配算法定位识别绝缘子, 获取绝缘子红外图像中的坐标参数, 并对其进行分割提取, 通过最小二乘线性拟合提取绝缘子表面温度。结合相关标准与仿真分析结果, 通过同类比较判断法对比多个绝缘子温度状态的差异, 实现劣化绝缘子检测。

Porcelain insulators are widely used in power distribution lines, but they are susceptible to deg-radation during operation owing to long-term electromechanical stress and harsh outdoor environments. Infrared thermal imaging is an important live insulator degradation detection method. It has the advantages of convenient detection, safety, high efficiency, and non-contact operation. It has become an important method in power inspection. However, the thermal image characteristics of faulty insulators are not evi-dent and cannot be recognized directly by the naked eye. Therefore, in this study, we first conduct a temperature field simulation analysis of porcelain insulators in distribution lines and then propose an in-frared thermal image detection method for faulty insulators. A multi-scale template matching algorithm is used to locate and identify the insulators. The coordinate parameters of the insulator in the infrared image are obtained, the insulator is segmented and extracted by multi-scale template matching, and the tempera-ture of the insulator is extracted by least-square linear fitting. Combined with the relevant standards and simulation analysis results, the differences in the temperature states among multiple insulators were com-pared using a similar comparison judgment method to detect faulty insulators.