摘要
针对小电流接地的直流配电网在发生高阻接地故障时故障辨识困难,以及电流差动保护易受分布电容暂态电流干扰的问题,提出一种基于差动电流积分相关性的直流配电网单极接地故障保护方法。研究通过分析直流配电网在发生故障后的故障电流特征,验证了分布电容暂态电流为故障电流的主要成分。利用发生区内外故障时差动电流的极性差异并引入Pearson相关性系数,根据正负差动电流积分与其积分绝对值的相关性构造故障线路识别判据。仿真分析表明,所提方法可快速识别故障线路,具有一定的耐受噪声和同步误差的能力,且在高阻接地情况下依旧能准确识别故障线路。
Targeting the problems of fault identification difficulty when a high-impedance grounding fault occurs in DC distribution networks with small-current grounding and current differential protection which is easy to be interfered by transient current from distributed capacitance,the paper proposes a single-pole grounding fault protection method for the DC distribution network based on differential current integral correlation.It is pointed out the transient current from the distributed capacitance is the primary component of fault current by analyzing the fault current characteristics of the DC distribution networks after faults occurs.Utilizing polarity difference in differential currents between faults occurring inside and outside the protected zone,and introducing Pearson correlation coefficient,a criterion for fault line identification is constructed based on the correlation between the integrals of positive and negative differential currents and their absolute values.The simulation analysis demonstrates that the proposed method can quickly identify faulty lines,has a certain ability of noise tolerance and synchronization error,and can accurately identify the faulty lines even under the high resistance earth condition.
作者
贾思强
崔双喜
JIA Siqiang;CUI Shuangxi(School of Electrical Engineering,Xinjiang University,Urumqi 830046,China)
出处
《智慧电力》
北大核心
2025年第1期107-114,共8页
Smart Power
基金
国家自然科学基金资助项目(52266018)。
关键词
直流配电网
小电流接地
高阻接地故障
差动电流
Pearson相关性
DC distribution network
small current grounding
high resistance earth fault
differential current
Pearson correlation
