基于首行波曲率半径的交直流互联电网交流输电线路单端量保护  

Single-terminal Protection of AC Transmission Lines in AC-DC Network Based on Curvature Radius of First Traveling Wave

作　　者：高淑萍[1,3] 段云青 宋国兵 郑瀚[1,3] 李晓芳 GAO Shuping;DUAN Yunqing;SONG Guobing;ZHENG Han;LI Xiaofang(School of Electrical and Control Engineering,Xi’an University of Science and Technology,Xi’an 710054,China;School of Electrical Engineering,Xi’an Jiaotong University,Xi’an 710049,China;Xi’an Key Laboratory of Electrical Equipment Condition Monitoring and Power Supply Security,Xi’an 710054,China)

机构地区：[1]西安科技大学电气与控制工程学院,陕西西安710054 [2]西安交通大学电气工程学院,陕西西安710049 [3]西安市电气设备状态监测与供电安全重点实验室,陕西西安710054

出　　处：《湖南大学学报（自然科学版）》2024年第6期148-158,共11页Journal of Hunan University:Natural Sciences

基　　金：国家自然科学基金资助项目(51777166);国家自然科学基金国际合作与交流项目(52061635105);国家电网有限公司总部科技项目(52094020006U)。

摘　　要：交直流互联电网中逆变侧交流输电线路故障特征与纯交流系统具有较大的差异性,传统交流输电线路的保护方案已经不再适用于逆变侧交流输电线路.首先,基于逆变侧交流输电线路发生区内、外故障时拓扑结构的不同,分别推导了两种情况下线模故障分量电流首行波的表达式,理论上明确了交流输电线路在发生区内、外故障时首行波波形特征的差异性.其次,采用小波变换模极大值法和Levenberg-Marquardt算法提取首行波曲率半径,构造了利用首行波曲率半径进行故障区域识别的高可靠性单端量保护方案.最后,在PSCAD/EMTDC中搭建交直流互联电网模型,使用MATLAB对保护方案进行验证.仿真结果表明:所提保护方案快速有效,可靠性高,耐受过渡电阻的能力较强,具有良好的抗噪声能力.The fault characteristics of inverter AC transmission lines in AC-DC interconnection networks are quite different from those of pure AC systems.The protection scheme of traditional AC transmission lines is no longer suitable for inverter AC transmission lines.First,based on the different topological structures of the inverter AC transmission line when the fault occurs inside and outside,the expressions of the first traveling wave of the down-mode fault component current are derived,respectively,and the difference of the first traveling wave characteristics of the AC transmission line when the fault occurs inside and outside is clarified theoretically.Then,wavelet transform mode maximum method and Levenberg-Marquardt algorithm are used to extract the curvature radius of the first traveling wave,and a high-reliability single-terminal protection scheme is constructed by using the curvature radius of the first traveling wave to identify the fault region.Finally,the AC-DC interconnection network model is built in PSCAD/EMTDC,and the protection scheme is verified by MATLAB.The simulation results show that the proposed protection scheme is fast and effective,has high reliability,strong resistance to transition resistance,and good anti-noise ability.

关 键 词：交直流互联电网 单端量保护 LEVENBERG-MARQUARDT算法 小波变换模极大值法 首行波曲率半径 

分 类 号：TM773[电气工程—电力系统及自动化] TM75