绝缘子伞裙缺陷诱发芯棒酥朽的起始与发展分析  

Analysis of the Initial Aging Point and Development Process of A Pre-decay-like Aged Insulator

作　　者：彭雅楠 李文栋[1] 曾世胤 刘玥琳 卢明 张力 张冠军[1] PENG Yanan;LI Wendong;ZENG Shiyin;LIU Yuelin;LU Ming;ZHANG Li;ZHANG Guanjun(State Key Laboratory of Electrical Insulation and Power Equipment(Xi’an Jiaotong University),Xi’an 710049,Shaanxi Province,China;State Grid Henan Electric Power Research Institute,Zhengzhou 450052,Henan Province,China;Xiangyang Guowang Composite Insulators Co.,Ltd.,Xiangyang 441057,Hubei Province,China)

机构地区：[1]电力设备电气绝缘国家重点实验室(西安交通大学),陕西省西安市710049 [2]国网河南省电力公司电力科学研究院,河南省郑州市450052 [3]襄阳国网合成绝缘子有限责任公司,湖北省襄阳市441057

出　　处：《电网技术》2025年第4期1698-1707,共10页Power System Technology

基　　金：国网河南省电力公司科技项目“复合绝缘子全生命周期运行状态评估与防护策略研究项目”(521702240006)。

摘　　要：复合绝缘子的酥朽老化难以跟踪和预测,且会导致绝缘子断串,严重危害电力系统的安全运行。主流观点认为酥朽老化起源于护套—芯棒内界面失效,然而,在一起500kV线路绝缘子异常温升故障中,发现内界面基本完好。该文开展了现场故障绝缘子样品的泄漏电流、局部放电、水扩散、工业计算机断层扫描(computed tomography scan,CT)、扫描电子显微镜(scanning electron microscopy,SEM)、傅里叶变换红外光谱(Fourier transform infrared spectroscopy,FTIR)等测试,定位该绝缘子老化起始点位于伞裙—护套界面处的硅橡胶硫化缺陷,老化从伞裙根部向内侵蚀,扩散并穿透护套,造成护套—芯棒界面初步失效。若该绝缘子继续挂网运行,可能最终导致酥朽,该故障被判定为酥朽老化的早期表现。进一步研究发现,该批次绝缘子存在填料团聚、混料硫化不均、室温硫化硅橡胶(room temperature vulcanization,RTV)涂覆欠佳等缺陷,据此提出了制造改进建议。该文为绝缘子异常温升研究提供了详细案例分析,揭示了酥朽早期发展过程,有助于制造厂家和运行单位严控产品质量,预防恶性事故,保障电网安全运行。Decay-like aging of composite insulators is difficult to track and predict,seriously jeopardizing the operation of power systems.Early diagnosis of decay-like aging is important for preventing accidents.Taking an insulator abnormal heating failure as an example.Through tests such as leakage current,partial discharge,water diffusion,industrial CT,SEM,FTIR,the initiation point and development process of aging are restored,and it is determined that the heating phenomena in this case is an early manifestation of decay-like aging.The aging initiation point of the insulator is a vulcanization defect at the skirt-housing interface,the aging spreads and penetrates the housing,causing the failure of rod-housing interface.Eventually,decay-like aging will occur.The study also found that this batch of insulators is substandard,including the uneven mixed filler and suboptimal RTV bonding.This article provides a detailed case analysis for insulator abnormal heating.Assist manufacturers and power grid operators in strict product quality control to prevent accidents.

关 键 词：复合绝缘子 酥朽老化 异常温升 硅橡胶粉化 工业CT无损检测 

分 类 号：TM721[电气工程—电力系统及自动化]