Fasani Damiano, Barbieri Luca, Villa Andrea, Palladini Daniele, Malgesini Roberto, D'Avanzo Giovanni, Buccella Giacomo, Gadia Paolo
RSE SpA-Ricerca sul Sistema Energetico, Via Raffaele Rubattino, 54, 20134 Milano, Italy.
Sensors (Basel). 2024 Feb 20;24(5):1359. doi: 10.3390/s24051359.
Composite insulators for high-voltage overhead lines have better performances and are lighter than traditional designs, especially in heavily polluted areas. However, since it is a relatively recent technology, reliable methods to perform live-line diagnostics are still under development, especially with regard to internal defects, which provide few external symptoms. Thermal cameras can be employed, but their use is not always straightforward as the sun radiation can hide the thermal footprint of internal degenerative effects. In this work, an optical E-field sensor has been used to diagnose the internal defects of a set of composite insulators (bandwidth 200 mHz-50 MHz, min. detectable E-field 100 V/m). Moreover, a modelling activity using finite elements has been carried out to identify the possible nature of the defects by comparing experimental E-field profiles with those simulated assuming a specific defect geometry. The results show that the sensor can detect the presence of an internal defect, since its presence distorts the E-field profile when compared to the profile of a sound insulator. Moreover, the measured E-field profiles are compatible with the corresponding simulated ones when a conductive defect is considered. However, it was observed that a defect whose conductivity is not at least two orders of magnitude greater than the conductivity of the surroundings remains undetected.
高压架空线路用复合绝缘子性能更佳，且比传统设计更轻，在重污染地区尤为如此。然而，由于这是一项相对较新的技术，用于进行带电诊断的可靠方法仍在开发中，特别是对于内部缺陷，其外部症状很少。可以使用热成像仪，但由于太阳辐射可能掩盖内部退化效应的热特征，其使用并不总是那么简单。在这项工作中，一种光学电场传感器被用于诊断一组复合绝缘子的内部缺陷（带宽200 mHz - 50 MHz，最小可检测电场100 V/m）。此外，已经开展了一项使用有限元的建模活动，通过将实验电场分布与假设特定缺陷几何形状模拟得到的分布进行比较，来确定缺陷的可能性质。结果表明，该传感器能够检测到内部缺陷的存在，因为与完好绝缘子的分布相比，内部缺陷的存在会使电场分布发生畸变。此外，当考虑导电缺陷时，测量得到的电场分布与相应的模拟分布是相符的。然而，据观察，对于电导率不比周围环境电导率至少大两个数量级的缺陷，该传感器仍无法检测到。
