引用本文: | 李倍,和敬涵,Tony Yip.一种基于相位相关电流差动的站域后备保护算法[J].电力系统保护与控制,2014,42(24):1-5.[点击复制] |
LI Bei,HE Jing-han,Tony YIP.A study of substation-area backup protection based on phase related current differential[J].Power System Protection and Control,2014,42(24):1-5[点击复制] |
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摘要: |
传统站域电流差动后备保护,存在当比率系数单调变化时,区内区外故障的灵敏性呈现相斥变化的缺点;以及在区外故障CT饱和情况下保护误动的弊端。为了克服上述缺点,提出了相位相关电流差动的站域后备保护算法。理论分析表明其随着比率系数的单调增加,在区内与区外故障灵敏性都增加;而随着接地电阻的增大,其相较传统差动灵敏性提高;同时其还能克服传统站域电流差动在区外故障CT饱和情况下保护误动的缺点。最后利用PSCAD软件搭建了站域模型,仿真结果验证了理论分析的正确性。 |
关键词: 相位相关 站域电流差动 CT饱和 接地电阻 后备保护 |
DOI:10.7667/j.issn.1674-3415.2014.24.001 |
投稿时间:2014-03-15修订日期:2014-05-25 |
基金项目:国家自然科学基金项目(51277009) |
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A study of substation-area backup protection based on phase related current differential |
LI Bei,HE Jing-han,Tony YIP |
(School of Electrical Engineering, Beijing Jiaotong University, Beijing 100044, China) |
Abstract: |
There is a drawback in traditional substation area current differential protection, when the scale factor k monotonously changes, the sensitivity of the internal and external fault will vary oppositely. This paper proposes a substation-area backup protection based on phase related current differential which use the multi points redundancy information. The analysis shows that when the scale factor k monotonically increases, sensitivity of the internal and external fault will increase together. As the increasing of ground resistance, sensitivity of fault will increase. On the other hand, when the external faults cause CT saturation, the traditional protection will mis-operate, but the new algorithm can overcome the shortcoming. At last, PSCAD/EMTDC is used to build a 220 kV substation model, simulation results verify the theoretical analysis. |
Key words: phase related substation area current differential CT saturation grounding impedance backup protection |