利用单端边界能量的直流输电线路全线速动保护  

A Whole-Line Fast Protection Scheme for HVDC Transmission Line Based on Single-Ended Boundary Energy

作　　者：杨亚宇 邰能灵[2] 谢卫[1] 郑晓冬[2] 马建军 Yang Yayu;Tai Nengling;Xie Wei;Zheng Xiaodong;Ma Jianjun(Logistics Engineering College Shanghai Maritime University,Shanghai,201306,China;Key Laboratory of Control of Power Transmission and Conversion Ministry of Education Shanghai Jiao Tong University,Shanghai,200240,China)

机构地区：[1]上海海事大学物流工程学院,上海201306 [2]上海交通大学电力传输与功率变换控制教育部重点实验室,上海200240

出　　处：《电工技术学报》2023年第9期2403-2417,共15页Transactions of China Electrotechnical Society

基　　金：国家自然科学基金(51877135);中国博士后科学基金(2021M692045);上海市科学技术委员会(19040501700)资助项目。

摘　　要：现有单端边界能量保护,难以区分整流侧区外故障和直流线路末端故障,单端复合式保护解决了此问题,但方法相对复杂。此外,利用边界对故障高频分量衰减作用的单端边界能量保护对装置采样频率要求较高。为解决以上问题,该文根据直流滤波器的分流特性、平波电抗器的分压特性,提出一种新型直流线路单端边界能量全线速动保护方案。整流侧区外故障时,整流侧保护安装处边界能量值小于整流侧平波电抗器阀侧的值;逆变侧区外故障时,整流侧保护安装处边界能量值小于区内故障时的值;区内故障时,整流侧保护安装处边界能量值大于整流侧平波电抗器阀侧的值,且大于逆变侧区外故障时保护安装处检测到的值。根据此特征构造区内外故障识别判据,考虑到利用双端故障信号选极速动性不足,进一步提出一种单端快速选极判据。该方案原理简单,对采样率要求低,易于工程实现。大量仿真结果表明,该方案速动性好,可靠性高,且具备较好的抗过渡电阻能力。Compared with high voltage alternating current(HVAC)power transmission systems,high-voltage direct current(HVDC)power transmission systems have lower power losses and more flexible power control capabilities.The HVDC transmission system plays an important role in modern new type power systems.Presently,the line protection methods operated in practical HVDC project include main protections and backup protections.The travelling-wave protection is widely used as the main protection.However,the transient travelling-wave signals would be weakened during high fault resistance grounded faults,which make it difficult to catch the wave-head.For backup protection methods,the voltage derivative protection and current differential protection operate with low reliability.As for the former,the rate of the voltage change may not reach the threshold,because high fault resistances could the attenuation of transient voltage caused by fault resistance.And the action speed of current differential protection is too slow to realize the protection function.Thus,the line protection methods in engineering applications can not completely meet the requirements of the practical HVDC project.To overcome these problems,some novel protection schemes have been proposed in recent years.However,the existing single-ended boundary energy protection schemes are not able to distinguish the remote end DC line faults from the rectifier-side-external faults.Single-ended hybrid protection methods overcome this problem,while these methods are complicated.In addition,the single-ended boundary energy protection schemes use the attenuation characteristic of line boundary on high frequency components to achieve fault identification.At the same time,these protection algorithms need a high sampling frequency.In view of the above problems,a novel single-end boundary energy based whole-line fast protection is proposed.During rectifier-side-external faults,the rectifier-line-side boundary energy is lower than the rectifier-valve-side boundary energy.During inverte

关 键 词：高压直流输电线路 线路保护 单端保护 边界能量 故障附加网络 

分 类 号：TM773[电气工程—电力系统及自动化]