摘要
配电网单相断线故障会导致过电压、人身伤亡、电机损坏等事故。为了降低该类故障的排查难度,提出了一种基于负序电压电流相关系数的单相断线故障诊断方法。首先在给出配电网单相断线负序等效网络的基础上研究了负序电压和电流的相位关系,指出配电网在各种单相断线形态下故障线路故障点上游区段的负序电压和电流满足相关系数为负,而健全线路、故障线路的健全支路以及故障点下游各区段的相关系数为正,最后结合该特征分别给出了基于就地馈线自动化、智能分布式馈线自动化以及集中式馈线自动化模式的单相断线故障区段定位与隔离方法。理论分析和基于PSCAD的仿真结果表明文中的单相断线诊断方法不受中性点接地方式、功率因数、过渡电阻和断线形态的影响,同时与智能分布式和集中式馈线自动化结合使用时仅传输逻辑信号,通信量小。
Single-phase line breakage fault may cause accidents such as overvoltage, personal injury, motor damage. Aiming to reduce the difficulty in finding such faults, a novel single-phase line breakage fault detection method based on correlation coefficient of negative sequence voltage and current is proposed. The relationship between the phases of the negative sequence voltage and current is analyzed based on the negative sequence network firstly. It points out that the correlation coefficients of the negative sequence voltage and current of segments located at the upstream of the fault point are negative, while those for segments located at the downstream of fault point, on the healthy lines and on the parallel branches of the faulty line are positive. Finally, location and isolation method of the single-phase line breakage fault is proposed based on the local type feeder automation mode, intelligent distributed feeder automation mode and centralized fault automation moderespectively. Theoretical analysis and PSCAD-based simulations show that the proposed single-phase line breakage fault detection method is immune to neutral grounding mode, power factor, transition resistance and single phase line breakage fault types. Meanwhile, forthatonlylogic signalsneed to be transmitted when combined with the intelligent distributed or centralized feeder automation modes, the communication burden isrelatively low.
作者
常仲学
宋国兵
张维
CHANG Zhongxue;SONG Guobing;ZHANG Wei(Shaanxi Key Laboratory of Smart Grid(Xi’an Jiaotong University),Xi’an 710049,Shaanxi Province,China)
出处
《电网技术》
EI
CSCD
北大核心
2020年第8期3065-3072,共8页
Power System Technology
基金
国家电网公司科技项目(5226SX1600U9)
陕西省重点研发计划项目(2019ZDLGY18-07)。
关键词
配电网
单相断线
负序网络
区段定位
馈线自动化
distribution network
single-phase line breakage fault
negative sequence network
fault segment location
feeder automation
