基于小电阻投入后扰动量标定的灵活接地系统定位新方法  

Novel Fault Location Based on Disturbance Calibration After Small Resistance Input in Flexible Grounding System

作　　者：王晓卫 张帆[1] 王毅钊 张志华 郭亮 梁振锋[1] WANG Xiaowei;ZHANG Fan;WANG Yizhao;ZHANG Zhihua;GUO Liang;LIANG Zhenfeng(School of Electrical Engineering,Xi’an University of Technology,Xi’an 710054,Shaanxi Province,China;State Grid Shaanxi Electric Power Research Institute,Xi’an 710100,Shaanxi Province,China;State Grid Jiangxi Electric Power Research Institute,Nanchang 330000,Jiangxi Province,China)

机构地区：[1]西安理工大学电气工程学院,陕西省西安市710054 [2]国网陕西省电力有限公司电力科学研究院,陕西省西安市710100 [3]国网江西省电力有限公司电力科学研究院,江西省南昌市330000

出　　处：《电网技术》2024年第3期1301-1310,共10页Power System Technology

基　　金：国家自然科学基金项目(52177114);国网陕西省电力有限公司科技项目(5226KY220006,5226KY230001);国网江西省电力有限公司科技项目(521820220016)。

摘　　要：针对传统行波定位方法应用于灵活接地配电系统时,存在定位误差大的问题,该文提出了一种基于小电阻投入后扰动量标定的灵活接地系统定位新方法。首先,通过投入并联小电阻产生扰动信号,该信号到达故障点后发生突变,产生线模行波信号;其次,利用多元变分模态分解(multivariate variational mode decomposition,MVMD)算法分解线模电流,提取故障特征,并计算最高频本征模态分量(intrinsic mode function,IMF)的离散峭度值,峭度值最大时刻即为线模电流到达时刻;最后,利用首端检测装置计算故障距离。针对灵活接地系统的复杂拓扑结构,研究了架空线、电缆线和混合线的定位公式,通过在末端增加辅助装置,排除伪故障点。仿真结果表明,所提方法能够准确实现故障定位,且不受故障初相角、过渡电阻及故障位置的影响。Aiming at the problems of the large fault location errors when the traditional traveling wave fault location is applied to the flexible ground distribution systems,this paper presents a novel method of fault location based on the disturbance calibration after the small resistance input in the flexible grounding system.Firstly,a disturbance signal is generated by putting in a small resistor in parallel.When it reaches the fault point this signal undergoes a sudden change,generating an aerial mode traveling wave signal.Secondly,by using the multivariate variational mode decomposition(MVMD)algorithm,the aerial mode current is decomposed and the fault features are extracted.Then,the discrete kurtosis value is calculated for the highest frequency intrinsic mode function(IMF)component.The moment of the maximum kurtosis is the arrival time of the aerial mode current.Finally,it adopts the head-end detection device to calculate the fault distance.For the complex topology of the flexible ground distribution systems,the localization equation of the overhead lines,the cable lines,and the hybrid lines are studied.The pseudo-fault points are excluded by adding the auxiliary devices at the branch end.The simulation results demonstrate that the proposed method is able to accurately locate faults and is not affected by the fault's initial phase angle,the transition resistance,and the fault location.

关 键 词：多元变分模态分解 峭度 灵活接地 故障定位 

分 类 号：TM721[电气工程—电力系统及自动化]