基于零序电流分布的配电网接地故障智能监测方法  

Intelligent Monitoring Method of Distribution Network Grounding Faults Based on Zero-sequence Current Distribution

作　　者：单旭 SHAN Xu(State Grid Pizhou County Electric Power Supply Company,Xuzhou 221300,China;Pizhou Suneng Electric Power Co.,Ltd.,Xuzhou 221300,China)

机构地区：[1]国网邳州市供电公司,江苏徐州221300 [2]邳州苏能电力有限公司,江苏徐州221300

出　　处：《电工技术》2023年第23期81-83,86,共4页Electric Engineering

摘　　要：常规的配电网接地故障监测多采用随机森林方法提取接地故障点的相位特征,适用范围具有较大的局限性,无法提取较为精确的相位特征,导致接地故障测距结果误差较大,监测结果准确性得不到保证。基于此,引入零序电流分布原理,提出了一种新的智能监测方法。首先,利用阈值法,对配电网电压信号进行降噪处理,滤除信号中的多余噪声。其次,基于零序电流分布原理,提取配电网接地故障点上下游零序电流暂态分量相位特征,得出接地故障点的相对相位差,定位配电网接地故障馈线。在此基础上,设计接地故障单侧智能监测方法,对配电网接地故障进行智能监测,得出接地故障到监测点的距离。根据实验结果可知,应用新的方法后,在接地故障距离逐渐增加的情况下,接地故障测距误差较小,均不超过2.5 mm,能够实现配电网接地故障高精度监测的目标。Conventional distribution network grounding fault monitoring mostly uses random forest method to extract phase characteristics of fault point,and thereby is largely limited in applicative scope and inferior in accuracy of extracted phase characteristics,resulting in unsatisfactory errors of fault location results and unreliable monitoring precision.In view of this,the present work proposes a new intelligent monitoring method by introducing the principle of zero-sequence current distribution.First distribution network's voltage signal is denoised to filter out redundant noises by using threshold method.Second based on zero-sequence current distribution principle,phase characteristics of transient components of upstream and downstream zero-sequence current with respect to the grounding fault point are extracted,and relative phase difference of fault point is obtained,which enables location of faulty feeder.On this basis,the one-side intelligent monitoring method of grounding fault is designed and applied to determining distance from grounding fault in a practical case.According to the experimental results,the proposed method can achieve small errors of less than 2.5 mm in fault location under gradually increasing distances of grounding faults,indicating its utility in realizing high-precision monitoring of distribution network grounding faults.

关 键 词：零序电流 配电网 故障 智能 分布 接地故障 监测 

分 类 号：TM721[电气工程—电力系统及自动化]