基于经验小波变换(EWT)的贯通式同相牵引直接供电系统纵向保护研究
Research on the longitudinal protection of a through-type cophase traction direct power supply system based on the empirical wavelet transform
李璐 1张泽端 2蔡旺 3庄启康 2毕贵红 2邓健 2陈仕龙 2阚小瑞2
作者信息
- 1. Faculty of Electric Power Engineering,Kunming University of Science and Technology,Kunming 650500,P.R.China;Brunel University London,London UB8 3PH,United Kingdom
- 2. Faculty of Electric Power Engineering,Kunming University of Science and Technology,Kunming 650500,P.R.China
- 3. Yunnan Power Grid Co.,Ltd.,Kunming 650041,P.R.China
- 折叠
摘要
根据贯通式同相牵引直接供电系统牵引网线路两端特有的边界结构特点,提出一种基于经验小波变换的牵引网线路纵联保护方案.由于边界对故障信号高频分量的衰减作用,导致区内外故障时,边界两侧高频暂态能量比值不同.区内故障时,区内线路两端检测点高频暂态能量均大于相邻线路检测点高频能量；区外故障时,区内线路检测点高频能量将小于相邻线路检测点高频能量.故采用经验小波变换对所采集的故障电流信号进行分解处理,得到故障信号高频暂态能量,利用牵引网线路两端,边界两侧高频暂态能量的差异构造牵引网线路纵联保护方案,在不同故障初始角,不同故障距离,不同过渡电阻故障场景下对所提保护方案进行仿真验证,实验结果表明,所提保护方案均能准确动作.
Abstract
This paper proposes a longitudinal protection scheme utilizing empirical wavelet transform(EWT)for a through-type cophase traction direct power supply system,where both sides of a traction network line exhibit a distinctive boundary structure.This approach capitalizes on the boundary's capacity to attenuate the high-frequency component of fault signals,resulting in a variation in the high-frequency transient energy ratio when faults occur inside or outside the line.During internal line faults,the high-frequency transient energy at the checkpoints located at both ends surpasses that of its neighboring lines.Conversely,for faults external to the line,the energy is lower compared to adjacent lines.EWT is employed to decompose the collected fault current signals,allowing access to the high-frequency transient energy.The longitudinal protection for the traction network line is established based on disparities between both ends of the traction network line and the high-frequency transient energy on either side of the boundary.Moreover,simulation verification through experimental results demonstrates the effectiveness of the proposed protection scheme across various initial fault angles,distances to faults,and fault transition resistances.
关键词
贯通式/同相牵引直接供电系统/牵引网/经验小波/纵联保护Key words
Through-type/Cophase traction direct power supply system/Traction network/Empirical wavelet transform(EWT)/Longitudinal protection引用本文复制引用
基金项目
National Natural Science Foundation of China(51767012)
Curriculum Ideological and Political Connotation Construction Project of Kunming University of Science and Technology(2021KS009)
Kunming University of Science and Technology Online Open Course(MOOC)Construction Project(202107)
出版年
2024
国家科技期刊平台
NSTL
万方数据