Zhang Zhongyuan, Huang Qilin, Geng Jianghai, Liu Qiyu, Zhang Simin
Hebei Key Laboratory of Power Transmission Equipment Security Defense, North China Electric Power University, Baoding 071003, China.
Polymers (Basel). 2022 Jun 28;14(13):2620. doi: 10.3390/polym14132620.
The deterioration of a composite insulator's mandrel will cause a serious power-grid accident, so it is necessary to find the defect as soon as possible. Infrared imaging is an effective means to detect mandrel-deterioration defects, but sheath-aging defects will cause trouble to screen mandrel deterioration. Therefore, it is urgent to distinguish the two defects. In this paper, two composite insulators that are out of service with different heating characteristics are tested and analyzed, and the temperature-rise characteristics are analyzed by building a simulation model. The results show that the temperature rise of composite insulators with oxidative decomposition of epoxy resin is large, and the range usually extends from the hardware of the high-voltage side to several umbrella skirts. The temperature rise caused by the composite insulator with the fiber completely wrapped by epoxy resin is small, which mainly occurs from the hardware to the first umbrella skirt. The simulation model constructed in this paper is consistent with the experimental results, which verifies the accuracy of the model. The model can distinguish the mandrel-deterioration defect and sheath-aging defect, and has guiding significance and important reference value for the detection rate of the mandrel-deterioration composite insulator and ensuring the safe and stable operation of the power grid.
复合绝缘子芯棒劣化会引发严重的电网事故，因此有必要尽快发现缺陷。红外成像技术是检测芯棒劣化缺陷的有效手段，但护套老化缺陷会给芯棒劣化的甄别带来干扰。所以，区分这两种缺陷迫在眉睫。本文对两个具有不同发热特性的退役复合绝缘子进行了测试分析，并通过建立仿真模型对其升温特性进行了分析。结果表明，环氧树脂发生氧化分解的复合绝缘子温升较大，范围通常从高压侧金具延伸至数个伞裙；纤维被环氧树脂完全包裹的复合绝缘子引起的温升较小，主要发生在从金具到第一个伞裙的部位。本文构建的仿真模型与实验结果一致，验证了模型的准确性。该模型能够区分芯棒劣化缺陷和护套老化缺陷，对提高芯棒劣化复合绝缘子的检测率以及保障电网安全稳定运行具有指导意义和重要参考价值。
