引用本文: | 郝奕华,陈朝晖,何进锋,李银红,石东源.非全相运行对线路零序电流保护的影响分析[J].电力系统保护与控制,2022,50(18):10-17.[点击复制] |
HAO Yihua,CHEN Zhao,huiHE Jinfeng,LI Yinhong,SHI Dongyuan.Analysis of the influence of non-full-phase operation on line zero-sequence current protection[J].Power System Protection and Control,2022,50(18):10-17[点击复制] |
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摘要: |
非全相运行是电力系统中一种常见的不对称运行状态,可能会对线路零序电流保护造成影响,使其失去选择性,发生越级动作。为此,研究了线路零序电流保护的整定计算原则,推导了发生短路故障和出现非全相运行状态时零序分支系数的计算公式,对两种情况下的零序分支系数计算公式进行了对比分析,并在此基础上分析了非全相运行状态下零序电流保护越级动作的原因,与短路故障相比,非全相运行时的零序分支系数越大,越容易发生越级动作。结合IEEE39节点系统算例,验证了非全相运行时零序分支系数的增大可能引起线路零序电流保护发生越级动作。最后,针对非全相运行时零序电流保护可能越级动作这一问题,从定值离线校验和在线管理两个方面给出了应对策略。 |
关键词: 非全相运行 线路零序电流保护 整定计算 零序分支系数 越级动作 |
DOI:DOI: 10.19783/j.cnki.pspc.211662 |
投稿时间:2021-12-07修订日期:2022-01-21 |
基金项目:国家重点研发计划项目资助(2016YFB0900100);国家自然科学基金项目资助(51777081) |
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Analysis of the influence of non-full-phase operation on line zero-sequence current protection |
HAO Yihua,CHEN Zhao,huiHE Jinfeng,LI Yinhong,SHI Dongyuan |
(1. State Key Laboratory of Advanced Electromagnetic Engineering and Technology (Huazhong University of Science and
Technology), Wuhan 430074, China; 2. China Southern Power Grid Power Dispatching and Control Center, Guangzhou
510663, China; 3. Liupanshui Power Supply Bureau, Guizhou Power Grid Co., Ltd., Liupanshui 553001, China) |
Abstract: |
Non-full-phase operation is a common asymmetric operational state in a power system. It will affect line zero-sequence current protection, causing it to lose selectivity and override. Therefore, the setting calculation principle of line zero-sequence current protection is studied. Then the calculation formulas of the zero-sequence branch coefficient under short-circuit fault and non-full-phase operation are deduced. By comparing the calculation formula of zero-sequence branch coefficient in two cases, the reason for the override of zero-sequence current protection under non-full-phase operation is analyzed. Compared with the zero-sequence branch coefficient of a short-circuit fault, the greater the zero-sequence branch coefficient of non-full-phase operation is, the easier the occurrence of override. Combined with the example of the IEEE39 bus system, it is verified that the increase of zero-sequence branch coefficient may cause the line zero-sequence current protection to override in the condition of non-full-phase operation. Finally, given the problem that zero-sequence current protection may override during non-full-phase operation, coping strategies are given from the two aspects of settings off-line verification and on-line management.
This work is supported by the National Key Research and Development Program of China (No. 2016YFB0900100). |
Key words: non-full-phase operation line zero-sequence current protection setting calculation zero-sequence branch coefficient override |