引用本文: | 金瑞,林湘宁,时伯年.同塔双回线接地距离保护应对事故过负荷的改进整定方法[J].电力自动化设备,2021,41(7): |
| JIN Rui,LIN Xiangning,SHI Bonian.Improved setting method of distance protection under post-fault overload condition of parallel transmission lines on same tower[J].Electric Power Automation Equipment,2021,41(7): |
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摘要: |
对于同塔双回线的距离保护,目前有应对事故过负荷情况的2类通用整定方法:一类是躲过系统静稳极限运行下发生邻线断线故障时的过负荷入侵;另一类是躲过线路热稳极限运行下发生邻线跳闸故障时的过负荷入侵,这2类通用整定方法均存在不能相互覆盖彼此盲区的缺陷。为此,首先计算出上述2种事故过负荷情况下健全线路的测量阻抗的变化量,比较了其负荷入侵的严重程度,在此基础上提出了一种兼顾2种过负荷情况的过负荷入侵阻抗定值的改进整定方法,并基于PSCAD/EMTDC仿真测试对比了3类整定方法的优劣。算例分析结果表明,与已有的2类整定方法相比,所提改进方法能在保证事故过负荷不误动的情况下兼顾较强的抗过渡电阻能力,更具合理性。 |
关键词: 同塔双回线 整定方法 负荷入侵阻抗 距离保护 事故过负荷 |
DOI:10.16081/j.epae.202105008 |
分类号:TM77 |
基金项目: |
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Improved setting method of distance protection under post-fault overload condition of parallel transmission lines on same tower |
JIN Rui1, LIN Xiangning2, SHI Bonian1
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1.Simulation Analysis Innovation Department, Beijing Sifang Automation Co.,Ltd.,Beijing 100085, China;2.State Key Laboratory of Advanced Electromagnetic Engineering and Technology, Huazhong University of Science and Technology, Wuhan 430074, China
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Abstract: |
Currently there are two universal methods of setting distance protection of parallel transmission lines for post-fault overload condition. One is setting under overload encroachment after open-line fault occurs at adjacent line during static stability limit operation. The other is setting under overload encroachment after adjacent line trips during thermal stability limit operation. Both setting methods have the disadvantage that they cannot cover each other’s blind zones. Aiming at this problem, the variation of measured impedance of healthy lines under the two post-fault overload conditions is calculated, and the severity of the two post-fault overload is compared. Based on these calculations, an improved setting method of load encroachment impedance under the two conditions is proposed. The three setting methods are compared via PSCAD/EMTDC software. The result shows that compared with the current two setting methods, the proposed setting method can detect large transition resistance and prevent mal-trip under post-fault overload condition at the same time, which is more reasonable. |
Key words: parallel transmission lines on same tower setting method load encroachment impedance distance protection post-fault overload |