| 引用本文: | 张卓凡,侯俊杰,樊艳芳,等.基于主动探测式的双端弱馈交流系统模型识别纵联保护[J].电力系统保护与控制,2026,54(09):26-38. |
| ZHANG ZhuOFan,HOU Junjie,FAN Yanfang,et al.Model identification pilot protection of dual-end weak-feed AC systems based on active detection[J].Power System Protection and Control,2026,54(09):26-38 |
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| 摘要: |
| 新能源经柔性直流输电系统的送出工程已成为实现大规模新能源并网的重要发展方向。双端弱馈交流系统的电源特征不同于传统同步机系统，且换流站存在整流、逆变两种运行模式，导致故障电流方向具有不确定性，这使得常规的模型识别纵联保护方案面临适应性问题。为此，提出一种基于主动探测式的双端弱馈交流系统模型识别纵联保护方案。首先研究了常规模型识别纵联保护在双端弱馈交流系统下线路保护的适用性。在此基础上，结合控制与保护协同的思想，利用双端弱馈交流系统换流站的高可控性特征，提出一种在差模环节叠加注入特征频率信号的控制策略，并分析了注入特征频率信号下线路模型的相位差异特征。最后，结合故障识别启动判据、故障识别主判据，构建了不受运行模式影响的模型识别纵联保护方案，并通过仿真验证了该方案的有效性。仿真结果表明，所提保护方案阈值无需仿真整定，不依赖于参数计算精度，能够可靠识别区内外故障，可以耐受 300 Ω 过渡电阻和 25 dB 噪声干扰，适用于双端弱馈交流系统。 |
| 关键词: 双端弱馈交流系统 主动注入控制策略 模型识别 纵联保护 |
| DOI：10.19783/j.cnki.pspc.250935 |
| 分类号: |
| 基金项目:国家自然科学基金项目资助(52567016，52442705)；新疆维吾尔自治区自然科学基金项目资助(2022D01C662)；国家重点研发计划项目资助(2021YFB1507000)：“天池英才引进”计划项目资助 |
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| Model identification pilot protection of dual-end weak-feed AC systems based on active detection |
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ZHANG Zhuofan1, HOU Junjie1, FAN Yanfang1, SONG Guobing1,2, WU Xiaofang3, ZHANG Changjian1
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1. School of Electrical Engineering, Xinjiang University, Urumqi 830046, China; 2. School of Electrical Engineering, Xi'an Jiaotong University, Xi'an 711049, China; 3. Electric Power Research Institute of State Grid Xinjiang Electric Power Co., Ltd., Urumqi 830011, China
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| Abstract: |
| The integration of renewable energy via flexible DC transmission systems has become an important development direction for enabling large-scale renewable energy grid connection. The power supply characteristics of dual-end weak-feed AC systems differ significantly from those of traditional synchronous generator-based systems. Moreover, the converter stations operate in rectifier and inverter modes, leading to uncertainty in the direction of fault currents. This poses adaptability challenges for conventional model identification-based pilot protection schemes. To address these issues, a model identification pilot protection scheme for dual-end weak-feed AC systems based on active detection is proposed. First, the applicability of conventional model identification-based pilot protection in such systems is studied. On this basis, considering the concept of coordinated control and protection, and leveraging the high controllability of converter stations, a control strategy is proposed in which a characteristic frequency signal is superimposed and injected into the differential-mode component. The phase difference characteristics of the line model under the injection characteristic frequency signal are then analyzed. Finally, by combining a fault detection initiation criterion and a main fault identification criterion, a model identification pilot protection scheme that is independent of operating modes is constructed. Simulation results verify the effectiveness of the proposed scheme. The results show that the thresholds of the proposed protection scheme do not require simulation-based tuning and are not dependent on the accuracy of parameter calculation. The scheme can reliably identify internal and external faults, withstand transition resistances up to 300 Ω and noise interference of 25 dB, and is suitable for double-ended weak-feed AC systems. |
| Key words: dual-end weak-feed AC system active injection control strategy model identification pilot protection |
