基于硅橡胶基调控的高压电缆缓冲层缺陷修复研究  

Research on Defect Rejuvenation of Buffer Layer for High Voltage Cable Based on Silicone Rubber Regulation

作　　者：凌颖 黄嘉盛 李濛 吴智恒 惠宝军 刘刚[2] LING Ying;HUANG Jiasheng;LI Meng;WU Zhiheng;HUI Baojun;LIU Gang(CSG Guangdong Guangzhou Power Supply Bureau,Guangzhou,Guangdong 510620,China;School of Electric Power Engineering,South China University of Technology,Guangzhou,Guangdong 510641,China;CSG Electric Power Research Institute Co.,Ltd.,Guangzhou,Guangdong 510663,China)

机构地区：[1]南方电网广东广州供电局,广东广州510620 [2]华南理工大学电力学院,广东广州510641 [3]南方电网科学研究院有限责任公司,广东广州510663

出　　处：《广东电力》2023年第7期84-93,共10页Guangdong Electric Power

基　　金：中国南方电网有限责任公司科技项目(GZHKJXM20190104)。

摘　　要：近年来,缓冲层放电造成的电缆本体击穿事故,对线路的运维检修提出了新的挑战,但目前鲜有抑制缓冲层放电的缺陷修复方法。制备含导电炭黑的加成型硅橡胶作为修复液,将其注入电缆气隙层后,对其修复缓冲层电气性能的情况展开研究。采用场发射扫描电子显微镜和电阻测量装置,从介观和宏观层面分析修复液的导电机理;同时建立高压电缆三维数值仿真模型,分析修复液注入体积以及电导率参数对缺陷电缆修复前后电场分布的影响;最后开展真型电缆局部放电试验,对比缺陷电缆在修复前后的局部放电情况。结果表明:当修复液电导率小于10-5 S/m时,电场强度主要受接触界面边缘曲率影响;当修复液电导率超过10-5 S/m后,其能够在绝缘屏蔽与铝护套之间构筑良好的导电通道,减小放电烧蚀的风险;修复液注入缺陷电缆后,能够显著抑制缓冲层放电现象,恢复缓冲层的电气性能。In recent years,the breakdown accident of the cable body caused by the discharge of buffer layer has posed new challenges to the operation and maintenance of the line.However,there are defect rejuvenation methods to restrain the discharge of the buffer layer.It is necessary to develop a new method to rejuvenate the defects of the buffer layer.By preparing a silicon rubber containing conductive carbon black as the rejuvenation fluid,this paper investigates the electrical properties of the buffer layer after the rejuvenation fluid is injected into the air gap layer of the cable.By using the field emission scanning electron microscopy and resistance measurement device,it analyzes the conductive mechanism of rejuvenation fluid both in mesoscopic and macroscopic aspects.It also establishes a 3D numerical simulation model of high voltage cable to analyze the impact of the injection volume of rejuvenation fluid and conductivity parameters on the electric field distribution of defective cable before and after rejuvenation.Finally,a partial discharge test is performed on the real cable to compare the partial discharge situation of the defective cable before and after rejuvenation.The results show that when the conductivity of the rejuvenation fluid is less than 10-5 S/m,the electric field strength is mainly affected by the curvature of the contact interface edge.When the conductivity exceeds 10-5 S/m,a good conductive channel can be constructed between the insulation shield and the aluminum sheath to reduce the risk of discharge ablation.After the rejuvenation fluid is injected into the defective cable,the discharge phenomenon of the buffer layer can be significantly suppressed and the electrical properties of the buffer layer restored.

关 键 词：高压电缆 缓冲层放电缺陷 修复方法 加成型导电硅橡胶 电场仿真 局部放电测试 

分 类 号：TM7207[电气工程—电力系统及自动化]