摘要
配电网高阻接地故障由于故障电流微弱而难以被传统保护装置检测并排除,故障长时间存在会增加发生火灾和人身安全事故的风险。针对现有方法在面对不同接地介质等故障场景时,因故障特征的差异性及噪声干扰而导致的整定阈值难设定和检测可靠性不足等问题,基于对10 k V电网现场实测高阻故障波形的分析,采用最小二乘线性拟合描述波形非线性畸变,提出基于零序电流波形区间斜率曲线的故障检测方法。同时,采用格拉布斯(Grubbs)法抑制不规则波形畸变对区间斜率曲线的干扰,以进一步保证算法对故障特征的正确提取。所提方法具有较强的抗噪声能力,数值仿真和现场实测故障数据验证了算法的可靠性。
High impedance grounding fault in the distribution network can hardly be detected and cleared by the traditional protective relays due to its weak fault current.The persistent existence of the fault increases the risks of fire hazards and human safety.Aiming at the problems of hard-determined setting threshold and insufficient detection reliability caused by the differences of fault characteristics and noise interference when the existing methods are facing different grounding dielectrics and fault scenarios,a fault detection method is proposed based on interval slope curves of zero sequence current according to the curve analysis of high impedance fault field test in a 10 k V power grid,which uses least squares linear fitting to describe the nonlinear distortion of curves.Meanwhile,Grubbs method is proposed to suppress the interference to interval slopes curves from the irregular waveform distortions and to further guarantee the proper extraction of the fault characteristics.The proposed method possesses strong immunity against noise and the reliability is verified by numerical simulation and field measured fault data.
作者
韦明杰
石访
张恒旭
徐丙垠
王鹏
WEI Mingjie;SHI Fang;ZHANG Hengxu;XU Bingyin;WANG Peng(Key Laboratory of Power System Intelligent Dispatch and Control of Ministry of Education(Shandong University),Jinan 250061,China;College of Electrical and Electronic Engineering,Shandong University of Technology,Zibo 255049,China;Electric Power RevSearch Institute of State Grid Henan Electric Power Company,Zhengzhou 450052,China)
出处
《电力系统自动化》
EI
CSCD
北大核心
2020年第14期164-171,共8页
Automation of Electric Power Systems
基金
国家重点研发计划资助项目(2017YFB0902800)
国家电网公司科技项目(52094017003D)。
关键词
配电网
高阻接地故障
波形畸变
最小二乘法
格拉布斯法
distribution network
high impedance grounding fault
waveform distortion
least square method
Grubbs method
作者简介
韦明杰(1995-),男,博士研究生,主要研究方向:电力系统故障检测与诊断技术,E-mail:wmj_sdu@163.com;石访(1982-),男,博士,副教授,主要研究方向:电力系统稳定分析与控制、配电网相量测量装置技术与应用,E-mail:shifang@sdu.edu.cn;通信作者:张恒旭(1975-),男,博士,教授,博士生导师,主要研究方向:电力系统同步测量、稳定分析与控制,E-mail:zhanghx@sdu.edu.cn。
