| 引用本文: | 李振兴,谭洪,叶诗韵,翁汉,李振华.应用DI极性与信号处理的UHVDC输电线路保护新方案[J].电力系统保护与控制,2018,46(15):68-75.[点击复制] |
| LI Zhenxing,TAN Hong,YE Shiyun,WENG Hanli,LI Zhenhua.A new scheme for UHVDC transmission line protection using ΔI polarity and signal processing[J].Power System Protection and Control,2018,46(15):68-75[点击复制] |
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| 摘要: |
| 行波传输延时、干扰信号直接影响到基于比幅式的直流输电线路电流突变保护的可靠性。为解决此问题，提出增加纵联电流差值作为启动判据，利用两端电流突变量构成极性判据，并基于极性的比较构成新的保护判据。为解决行波传输延时问题，详细分析了延时机理，提出了一种在正常及区外故障时完全补偿延时的误差修正方案。为解决直流特征谐波、双极间的电磁耦合以及雷电高频脉冲等干扰信号的影响，通过采取Chebyshev数字滤波器得到较好的信号提取结果。基于PSCAD/EMTDC的仿真验证，该保护方案原理简单、可靠性高、采样率低。仿真结果显示，该方案具有很强的耐过渡电阻能力。 |
| 关键词: 行波保护 电流突变特性 分布参数模型 Chebyshev滤波器 |
| DOI：10.7667/PSPC171113 |
| 投稿时间：2017-07-25修订日期：2017-09-20 |
| 基金项目:国家自然科学基金项目资助(51607106);湖北省教育厅科学技术研究计划重点资助项目(D20171203) |
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| A new scheme for UHVDC transmission line protection using ΔI polarity and signal processing |
| LI Zhenxing,TAN Hong,YE Shiyun,WENG Hanli,LI Zhenhua |
| (College of Electrical Engineering & New Energy, China Three Gorges University, Yichang 443002, China;Hubei Provincial Key Laboratory for Operation and Control of Cascaded Hydropower Station, China Three Gorges University, Yichang 443002, China) |
| Abstract: |
| The transmission delay and interference signal of traveling wave directly affect the reliability of current mutation protection based on amplitude ratio DC transmission line. In order to solve this problem, this paper proposes to increase the longitudinal current difference as the starting criterion. The polarity criterion is constructed by using the current sudden change at both ends, and a new protection criterion is constructed based on the polarity comparison. Furthermore, in order to solve the delay problem of traveling wave transmission, the delay mechanism is analyzed in detail, and an error correction scheme is proposed to compensate the full delay in normal and out of the loop faults. In order to solve the DC characteristics of bipolar harmonics, the electromagnetic coupling between lightning and high-frequency pulse interference signals, Chebyshev window filter are adopted to get a better signal extraction results. Through the simulation of PSCAD/EMTDC, the protection scheme has simple principle, high reliability and low sampling rate. The result shows that the scheme has strong resistance to excessive resistance. This work is supported by National Natural Science Foundation of China (No. 51607106). |
| Key words: traveling wave protection characteristics of changing current distributed parameter model Chebyshev window filter |
