径向电流作用下的高压电缆缓冲层烧蚀多物理量信号演变规律  

Evolution Law of Multi-physical Signal of High-voltage Cable Buffer Layer Ablation Under Radial Current

作　　者：吴明[1] 洪涵韬 任志刚 张云飞[1] 李建英[1] 高景晖 WU Ming;HONG Hantao;REN Zhigang;ZHANG Yunfei;LI Jianying;GAO Jinghui(State Key Laboratory of Electrical Insulation and Power Equipment,Xi’an Jiaotong University,Xi’an 710049,China;Beijing Electric Power Research Institute,State Grid Beijing Electric Power Company,Beijing 100075,China)

机构地区：[1]西安交通大学电工材料电气绝缘全国重点实验室,西安710049 [2]国网北京市电力公司电力科学研究院,北京100075

出　　处：《高电压技术》2025年第2期936-945,共10页High Voltage Engineering

基　　金：国家自然科学基金(51977169);中央高校基本科研业务费专项资金(xzy012023152;xtr062023001);电工材料电气绝缘全国重点实验室中青年基础研究创新基金(EIPE22315)。

摘　　要：近年来高压电缆中缓冲层烧蚀导致的电缆本体击穿事故频发,严重影响了电网的安全稳定运行。缓冲层的含水率及外界压力是影响高压电缆缓冲层烧蚀故障发展的重要因素。基于此,搭建了缓冲层在不同含水率及不同受力下的烧蚀模拟试验平台,研究不同条件下缓冲层烧蚀产生的温度、超声以及电信号,获得了烧蚀缺陷的多物理量演变规律。同时结合对烧蚀缓冲层的微观形貌特征以及烧蚀产物成分的表征,分析了不同条件下的缓冲层烧蚀信号产生的机理,发现电流径向集中引起的热效应和缓冲层内气隙放电是导致缓冲层温度升高的原因,而气隙放电是导致超声信号和电信号产生的原因。研究发现,相较干燥缓冲层烧蚀,含水情况下的缓冲层会和铝护套发生电化学腐蚀,会使得超声信号和电信号变大,且中间会有小的信号产生。该研究为高压电缆缓冲层烧蚀检测装置的开发提供了理论和实验基础。In recent years,incidents of cable insulation breakdown due to the ablation of the insulating layer in high-voltage cables have become increasingly frequent,significantly impairing the safe and stable operation of power grids.The moisture content and external pressure of the insulating layer are crucial factors influencing the development of ablation failures in high-voltage cables.In light of this,we establish a simulation test platform for the ablation of the in-sulating layer under varying moisture content and different mechanical loads.Moreover,we investigate the temperature,ultrasound,and electrical signals generated by ablation under different conditions and provide insights into the evolution of multiple physical parameters associated with ablation defects.Combining microscopic surface features of the eroded insulating layer and the characterization of ablation product composition,we analyze the mechanisms behind ablation signal generation under different conditions.It is discovered that the localized heating caused by radial current concentra-tion and partial discharge within the insulating layer are the main contributors to elevated temperatures in the insulating layer.Additionally,it is found that partial discharge is the primary cause of ultrasound and electrical signal generation.The study reveals that,compared to dry insulating layer ablation,the presence of moisture in the insulating layer leads to electrochemical corrosion of the aluminum sheath,resulting in increased ultrasound and electrical signals,with occasional minor signal generation in between.This research provides both theoretical and experimental foundations for the devel-opment of high-voltage cable insulation ablation detection devices.

关 键 词：电力电缆 缓冲层 烧蚀故障 超声信号 径向电流 

分 类 号：TM7[电气工程—电力系统及自动化]