基于系统电力扰动的交叉互联电缆绝缘整体老化在线监测  

On-Line Monitoring of Insulation Overall Aging for Cross-Bonded Cables Based on System Power Disturbances

作　　者：李露露[1] 雍静[1] 曾礼强[1] 王晓静[1] 陆家明 Li Lulu;Yong Jing;Zeng Liqiang;Wang Xiaojing;Lu Jiaming(State Key Laboratory of Power Transmission Equipment&System Security and New Technology Chongqing University Chongqing 400030 China)

机构地区：[1]输配电装备及系统安全与新技术国家重点实验室(重庆大学),重庆400030

出　　处：《电工技术学报》2018年第14期3396-3405,共10页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(51777021);输配电装备及系统安全与新技术国家重点实验室(重庆大学)项目(2007DA10512716406)资助

摘　　要：工频激励下交叉互联电缆绝缘监测信号微弱、绝缘状态分辨困难,因此提出一种基于系统电力扰动的绝缘整体老化在线监测新方法。该方法利用系统电力扰动下接地线、交叉互联线上的电流暂态响应,通过计算绝缘导纳频谱实现电缆的整体老化状态辨别。分析并选取了合适的系统电力扰动,构建适用于系统电力扰动分析的交叉互联电缆频变模型;针对金属屏蔽线交叉互联的连接方式,提出使电缆三相独立求解的解耦方法,并推导绝缘导纳频谱的计算公式。基于矢量拟合法在EMTP/ATP软件中搭建电缆模型,选取单相接地、相间短路、电容投切、空载线路充电作为系统电力扰动的典型代表,仿真结果表明该方法的正确性和有效性。The insulation monitoring signals of cross-bonded cables are generally weak and insulation states are difficult to distinguish under power frequency excitation.A new on-line monitoring method based on system power disturbances is proposed for insulation ageing of cross-bonded cable insulation states.This method uses the insulation admittance spectrum to distinguish the overall aging conditions,which are calculated by the current transient responses on the grounding line and cross-bonding line under the system power disturbances.The suitable types of power disturbances are analyzed and selected,and a frequency-dependent cross-bonded cable model for system power disturbances analyzing is constructed.A three-phase decoupling method is proposed to solve each phase independently for the cross-bonded scheme of the metal sheath,and the formula of calculating the insulation admittance spectrum is deduced.A simulation model is built based on vector fitting method in EMTP/ATP software.The single-phase grounding,inter-phase short circuit,capacitor switching and unloaded line charging are selected as the typical representatives of system power disturbances.The simulation results have proved that this method is correct and effective.

关 键 词：电力扰动 绝缘在线监测 交叉互联电缆 导纳频谱 

分 类 号：TM85[电气工程—高电压与绝缘技术]