基于故障行波差异性的柔性直流输电线路纵联保护  

Pilot Protection for Flexible HVDC Transmission Lines Based on the Difference of Fault Traveling Waves

作　　者：贾科 姚昆鹏 刘子奕 陈淼 李再男 毕天姝 JIA Ke;YAO Kunpeng;LIU Ziyi;CHEN Miao;LI Zainan;BI Tianshu(State Key Laboratory of Alternate Electrical Power System With Renewable Energy Sources(North China Electric Power University),Changping District,Beijing 102206,China;State Grid Tianjin Electric Power Company High Voltage Branch,Hebei District,Tianjin 300232,China)

机构地区：[1]新能源电力系统国家重点实验室(华北电力大学),北京市昌平区102206 [2]国网天津市电力公司高压分公司,天津市河北区300232

出　　处：《中国电机工程学报》2024年第7期2616-2627,I0009,共13页Proceedings of the CSEE

基　　金：国家自然科学基金(面上项目)(51777071)。

摘　　要：柔性直流输电对解决大规模新能源的消纳问题具有重要意义,其中行波保护是保障系统安全的关键。然而采用行波幅值比较判据区内外故障的保护对故障前、反行波幅值关系分析并不严谨,行波反射关系式仅在复频域下成立,若将此关系推广到时域中可能影响保护的动作性能,给系统安全埋下隐患。针对这一问题,该文首先从理论上分析行波幅值比较式方向纵联保护的不足,并从区内故障验证出保护失效的边界。为具体揭示故障前、反行波的差异性,该文定量分析电压反行波与电流行波在一定时间内的极性,进而提出一种采用多点均值的电压行波方向识别判据并构成纵联保护。大量仿真结果表明,所提保护能够快速、可靠地识别线路区内外故障,具有较强的耐受过渡电阻能力与抗干扰能力。Flexible HVDC transmission is of great significance to solve the problem of long-distance consumption of large-scale new energy,and its traveling wave protection is the key to ensuring system safety.However,the existing traveling wave amplitude comparison protection is not rigorous in analyzing the relationship on traveling wave amplitude,and the traveling wave reflection relationship is only valid in the complex frequency domain.If this relationship is extended to the time domain,it may affect the protection action performance and bury hidden dangers for the system safety.To solve this problem,this paper first theoretically analyzes the shortcomings of the existing traveling wave amplitude comparison protection,and verifies the time period when the amplitude of the forward traveling wave is greater than that of the backward traveling wave.In order to reveal the difference of traveling waves,the polarity of voltage backward traveling wave and current traveling wave is quantitatively analyzed,and then a voltage traveling wave fault identification criterion using multi-point mean is proposed.A large number of simulation results indicate that the proposed protection is not affected by the fault resistance,and it can quickly and reliably discriminate internal fault from external faults,as well as has strong sensitivity and anti-interference ability.

关 键 词：柔性直流输电 行波差异性 多点均值 纵联保护 

分 类 号：TM721[电气工程—电力系统及自动化] TM773