摘要
针对混合三端直流输电线路保护难以兼顾速动性与选择性的问题,提出一种基于随机矩阵理论的非单元式纵联保护。分析发现,混合三端直流线路区内、区外故障时,线路各测点电压、电流突变量方向不同。首先,利用各测点电压、电流突变量复制、平移构成随机矩阵并计算各矩阵特征值;其次,结合单环定理与特征根统计量进行区内、区外故障识别以及故障区段定位;最后计算故障区段极波能量比值实现故障选极。基于实时数字仿真器(RTDS)搭建混合三端直流系统进行测试分析。测试结果表明,所提保护判据简单可靠,耐受高阻能力强,在不同故障情况下均能快速准确识别区内外故障、故障区段及故障极,不需要同步时钟且对通信通道要求低。
Aiming at the problem that the protection of hybrid three-terminal DC transmission lines is difficult to take into account both speed and selectivity,a non-unit pilot protection based on random matrix theory is proposed.It is found that the directions of voltage and current break variables at each measuring point of the mixed three-terminal DC lines are different between internal and external faults.Firstly,the random matrix is formed by copying and translating the voltage and current break variables at each measuring point,and the eigenvalues of each matrix are calculated.Secondly,the internal and external fault identification and fault section location are carried out by combining the ring law and eigenvalue statistics.Finally,the ratio of polar wave energy in fault section is calculated to realize fault pole selection.Based on real-time digital simulator(RTDS),a hybrid three-terminal DC system is built for test and analysis.The test results show that the proposed protection criterion is simple and reliable,has strong resistance to high resistance,can quickly and accurately identify internal and external faults,fault sections and fault poles under different fault conditions,does not need clock synchronous,and has low requirements for communication channels.
作者
束洪春
王广雪
田鑫萃
代月
雷顺广
何廷一
SHU Hongchun;WANG Guangxue;TIAN Xincui;DAI Yue;LEI Shunguang;HE Tingyi(Faculty of Electric Power Engineering,Kunming University of Science and Technology,Kunming 650500,China;Faculty of Land Resource Engineering,Kunming University of Science and Technology,Kunming 650032,China;Electric Power Research Institute of Yunnan Electric Power Grid Co.,Ltd.,Kunming 650011,China)
出处
《电力系统自动化》
EI
CSCD
北大核心
2022年第19期162-171,共10页
Automation of Electric Power Systems
基金
国家自然科学基金重点资助项目(52037003)
云南省重大科技专项计划项目(202002AF080001)。
关键词
高压直流输电
纵联保护
极波能量比
随机矩阵理论
high voltage direct current transmission
pilot protection
polar wave energy ratio
random matrix theory
