摘要
逆变型分布式电源复杂的故障特性以及系统的故障穿越电流导致传统电流差动保护和基于波形相似度的保护方法动作性能下降。文中提出了一种基于时域波形积分的自适应电流差动保护方法。通过分析保护两端正序电流在区内外故障时的幅相特性,构造波形差异指数定量描述两端电流波形的差异程度,并通过对数函数放大此差异,进而构建了差动保护的自适应制动系数。通过计算虚拟T接支路电流构造补偿判据,以解决多条不可测负荷分支对保护可靠性的影响。仿真结果验证了所提方法具有传输数据量少、耐过渡电阻能力强以及不受T接支路影响等优点。
The complex fault characteristics of inverter-interfaced distributed generators(IIDGs)and system fault ride-through currents degrade the performance of traditional current differential protection and waveform similarity-based methods.This paper proposes an adaptive current differential protection scheme based on time-domain waveform integration.By analyzing the amplitude-phase characteristics of positive-sequence currents at both protection terminals during internal and external faults,a waveform difference index is constructed to quantitatively evaluate the dissimilarity between current waveforms.This index is amplified via a logarithmic function to establish an adaptive restraint coefficient for differential protection.Additionally,a compensation criterion is developed by calculating the virtual T-connected branch current,mitigating the impact of multiple unmeasurable load branches on protection reliability.Simulation results validate the advantages of the proposed method,including reduced data transmission requirements,strong tolerance to transition resistances,and immunity to T-connected branch effects.
作者
李响
周成瀚
邹贵彬
田君杨
李海勇
LI Xiang;ZHOU Chenghan;ZOU Guibin;TIAN Junyang;LI Haiyong(School of Electrical Engineering,Shandong University,Jinan 250061,China;Electric Power Research Institute of State Grid Shandong Electric Power Company,Jinan 250003,China;Power Dispatching Control Center of Guangxi Power Grid,Nanning 530023,China)
出处
《电力系统自动化》
北大核心
2025年第14期181-189,共9页
Automation of Electric Power Systems
基金
广西电网有限责任公司科技项目(046000KK52230003)
山东省自然科学基金资助项目(ZR2024ME009)。
关键词
有源配电网
正序电流
电流差动保护
时域波形
分布式电源
可靠性
active distribution network
positive-sequence current
current differential protection
time-domain waveform
distributed generator
reliability
