摘要
在高压直流输电系统中,换流变压器空载合闸时会出现励磁涌流,励磁涌流中包含非对称性励磁涌流和对称性励磁涌流,在不同的工况下励磁涌流的幅值和衰减速度不同,依靠传统的二次谐波制动方法难以准确地识别励磁涌流。为此,提出一种基于换流变差流模值分布特征的励磁涌流识别方法。该方法通过分相识别的方式构建励磁涌流识别的启动判据,并根据换流变不同差流的模值特征提出了基于换流变差流模值原始采样值和微分采样值的励磁涌流识别判据。借助仿真软件对不同励磁涌流工况进行仿真,结果表明,基于换流变差流模值分布特征的励磁涌流识别方法准确可靠,能有效识别励磁涌流,防止差动保护误动作。
In high-voltage direct current transmi-ssion systems,converter transformers experience significant inrush currents during no-load switching operations.These currents exhibit both asymmetrical and symmetrical components,with amplitudes and decay rates varying considerably under diverse conditions.Traditional methods depending solely on second harmonic braking often fail to accurately identify inrush currents.Consequently,this paper proposes a novel inrush current identification method for converter transformers based on the distinct distribution characteristics of differential current magnitudes.The method develops initiation criteria for identifying excitation inrush currents through phase-based analysis and establishes precise identification criteria.These criteria utilize the original and differential sampling values of differential current magnitudes,specifically tailored to the unique characteristics of different differential currents in converter transformers.With the help of simulation software,various inrush current scenarios were modeled.Results demonstrate that the proposed identification method is both accurate and reliable,successfully distinguishing inrush currents and effectively preventing maloperation of differential protection.
作者
李振兴
王钧杰
张红跃
胡聪
翁汉琍
LI Zhenxing;WANG Junjie;ZHANG Hongyue;HU Cong;WENG Hanli(School of Electrical Engineering and New Energy,China Three Gorges University,Yichang 443002,Hubei,China;XJ Electric Co.,Ltd.,Xuchang 461000,Henan,China)
出处
《电网与清洁能源》
北大核心
2025年第8期20-30,39,共12页
Power System and Clean Energy
基金
国家自然科学基金项目(52077120)。
关键词
换流变压器
差流模值
差动保护
励磁涌流
分相识别
converter transformers
differential current magnitudes
differential protection
inrush current
phase-based recognition
作者简介
李振兴(1977-),男,博士,教授,研究方向为电力系统继电保护;王钧杰(1999-),男,硕士研究生,研究方向为电力系统继电保护;翁汉琍(1980-),女,博士,教授,研究方向为电力系统继电保护。
