摘要
为应对分布式电源接入带来的保护问题,电流差动保护已开始应用于有源配电网。在配电网馈线区段中,常有T接变压器或感应电动机类型的负荷分支,其产生的非故障暂态电流可能导致电流差动保护误动。针对该问题,分析了T接暂态电流可能引起差动保护误动的多个场景。在此基础上,结合暂态电流波形特点,提出了一种基于差动电流正序分量衰减特征的闭锁方案。该方案采用傅里叶算法提取电流基波幅值,通过正序电流幅值衰减率区分故障差流和非故障暂态差流。仿真结果和现场数据验证表明,所提方案能够在不降低差动保护灵敏度的前提下,有效规避T接变压器或感应电机引起的保护误动风险。
To address protection issues arising from distributed generation integration,current differential protection has been increasingly applied in active distribution networks.In distribution feeder sections,T-connected load branches,such as transformers or induction motors,are commonly present.The non-fault transient currents generated by these branches may lead to the maloperation of current differential protection.Focusing on this problem,this paper analyzes multiple scenarios where T-connected transient currents may cause differential protection maloperation.Based on the characteristics of transient current waveforms,a blocking scheme based on the attenuation characteristics of the positive-sequence component of the differential current is proposed.This scheme employs the Fourier algorithm to extract the fundamental current amplitude and distinguishes fault differential currents from non-fault transient differential currents according to the attenuation rate of the positive-sequence current amplitude.Simulation results and field data verification demonstrate that the proposed scheme can effectively avoid the risk of protection maloperation caused by T-connected transformers or induction motors without compromising the sensitivity of current differential protection.
作者
林浩然
孔维娜
褚福亮
袁通
杨明耀
高厚磊
LIN Haoran;KONG Weina;CHU Fuliang;YUAN Tong;YANG Mingyao;GAO Houlei(Jining Power Supply Company,State Grid Shandong Electric Power Company,Jining 272000,China;School of Electrical Engineering,Shandong University,Jinan 250061,China)
出处
《电力系统保护与控制》
北大核心
2026年第6期83-93,共11页
Power System Protection and Control
基金
国家自然科学基金项目资助(52277109)。
关键词
T接负荷分支
暂态电流
闭锁方案
电流差动保护
有源配电网
T-connected load branch
transient current
blocking scheme
current differential protection
active distribution network
