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
高淑萍 1段云青 1宋国兵 2郑瀚 1李晓芳1
作者信息
- 1. 西安科技大学 电气与控制工程学院,陕西 西安 710054;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
- 2. 西安交通大学 电气工程学院,陕西 西安 710049
- 折叠
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.
Abstract
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Key words
AC/DC interconnection network/single end protection/levenberg-marquardt algorithm/wavelet transform mode maximum method/radius of curvature of first traveling wave引用本文复制引用
基金项目
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)
出版年
2024
国家科技期刊平台
NSTL
万方数据