中国电机工程学报2024，Vol.44Issue(7)：2604-2615,后插8,13.DOI:10.13334/j.0258-8013.pcsee.221953
基于双端初始电流行波时频矩阵相似度的柔性直流输电线路保护原理
VSC-HVDC Line Protection Principle Based on the Similarity of the Double-ended Initial Current Traveling Wave Time-frequency Matrices
摘要
Abstract
Aiming at the problems currently existing in line protection for voltage source converter-based high voltage DC(VSC-HVDC)grids,a double-ended protection principle based on similarity of time-frequency matrix of initial current traveling wave(ICTW)is proposed.First,the fault characteristics of the ICTWs on both sides of the line in the flexible DC grids under internal and external faults are analyzed.It is concluded that within a specific time window,the frequency-domain similarities of the double-ended ICTWs under internal faults are much higher than those under external faults.Then,the double-ended ICTWs are performed S-transform,and the time-frequency matrices are obtained.Then singular value decomposition(SVD)is performed on the matrices.Afterwards,the similarity calculation formula of the double-ended ICTWs is constructed based on the feature matrices,and the internal and external faults can be identified by the value of the similarity.In addition,lightning interference is identified according to the high and low frequency energy ratio of the ICTWs at both ends of the line.Finally,the simulation results under various fault conditions show that the protection scheme does not rely on line boundary elements;it can protect the full length of lines with different lengths;it has stronger robustness against transition resistance and noise.Besides,it satisfies the quick identification requirements of the main protection for VSC-HVDC grids.关键词
双端量保护/柔性直流(VSC-HVDC)电网/初始电流行波(ICTW)/时频矩阵/相似度Key words
double-ended protection/voltage source converter-based high voltage DC(VSC-HVDC)grid/initial current traveling wave(IVTW)/time-frequency matrix/similarity分类
信息技术与安全科学引用本文复制引用
张韵琦,王聪博,余越,杨国生,曹虹..基于双端初始电流行波时频矩阵相似度的柔性直流输电线路保护原理[J].中国电机工程学报,2024,44(7):2604-2615,后插8,13.基金项目
中国电力科学研究院科技项目(JB83-21-010).Project Supported by the Science and Technology Project of China Electric Power Research Institute(JB83-21-010). （JB83-21-010）
