基于权重修正D-S理论多判据融合的含新能源低压配网中性线断线判别方法  

multi-criteria fusion method for identifying broken neutral lines in low-voltage distribution networks containing new energy sources based on weight-correction D-S theory

作　　者：孙佳航 王楷杰 黄景光[1] 李正天[2] 林湘宁[2] 李浙栋 赵珩 梅诺男 SUN Jiahang;WANG Kaijie;HUANG Jingguang;LI Zhengtian;LIN Xiangning;LI Zhedong;ZHAO Heng;MEI Nuonan(College of Electrical Engineering and New Energy,China Three Gorges University,Yichang 443002,China;State Key Laboratory of Advanced Electromagnetic Engineering and Technology(Huazhong University of Science and Technology),Wuhan 430074,China)

机构地区：[1]三峡大学电气与新能源学院,湖北宜昌443002 [2]强电磁工程与新技术国家重点实验室(华中科技大学),湖北武汉430074

出　　处：《电力系统保护与控制》2023年第11期1-14,共14页Power System Protection and Control

基　　金：国家自然科学基金项目资助(52077120)。

摘　　要：中性线断线故障的识别与定位对低压配电网的故障诊断有重要作用。但传统基于电流或电压故障特征量的断线检测方法会因负载的波动和其不平衡度的大小而导致漏判误判,并且随着大规模分布式新能源的接入,故障特征随着低压配电网拓扑结构的改变而改变,传统故障识别判据不再精确有效。为此,在考虑新能源接入的情况下提出了一种基于权重修正D-S理论多判据融合的中性线断线检测方法。根据中性线断线故障特性的分析结果,分别对基于中性线电流和三次谐波电流变化的电流故障特征判据以及基于中性点偏移电压的电压故障特征判据进行改进,修正新能源接入对多种判据带来的影响。最后基于动态临近历史数据的判断结果,采用权重修正D-S证据理论将改进电流、电压多个判据信息进行融合,形成中性线断线故障综合判据。该方法能够提高对不同场景的适应度,并解决传统检测带来的误判问题。仿真结果验证了该方案的有效性。The identification and location of neutral line breakage faults are important for fault diagnosis in low voltage distribution networks,but traditional breakage detection methods based on current or voltage fault characteristics can lead to missed faults and misjudgements because of fluctuations in load and its imbalance.With the access of large-scale distributed new energy sources,fault characteristics change with the change of low voltage distribution network topology,and traditional fault identification criteria are no longer accurate nor effective.In this paper,a multi-criteria fusion method based on weight-correction D-S theory is proposed for neutral line break detection considering new energy access.Based on the analysis of the neutral break fault characteristics,the current fault characteristics based on the neutral and third harmonic current variations and the voltage fault characteristics based on the neutral offset voltage are improved.The impact of the new energy access on the multiple criteria is corrected.Finally,based on dynamic proximity history data,the D-S evidence theory is used to fuse the improved current and voltage multiple criteria information based on the results of the data.The D-S evidence theory is used to fuse the information of the improved current and voltage criteria to form a comprehensive neutral break fault criterion.The method improves the adaptability to different scenarios and solves the problem of misclassification caused by traditional detection.Simulation results verify the effectiveness of the solution.This work is supported by the National Natural Science Foundation of China(No.52077120).

关 键 词：低压配电系统 中性线断线 故障判别 分布式新能源 D-S证据理论 

分 类 号：TM73[电气工程—电力系统及自动化]