| 引用本文: | 王 洋,赵若阳,李大勇,等.基于故障相相间电流的有源配电网新型电流差动保护方法[J].电力系统保护与控制,2025,53(21):109-120.[点击复制] |
| WANG Yang,ZHAO Ruoyang,LI Dayong,et al.A new current differential protection method for active distribution networks based on fault-phase interline currents[J].Power System Protection and Control,2025,53(21):109-120[点击复制] |
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| 摘要: |
| 为解决分布式电源(distributed generator, DG)接入配电网导致传统保护难以适用的问题，基于故障相相间电流，提出一种适用于有源配电网的新型电流差动保护方法。首先，考虑不同类型DG在低电压穿越期间的控制策略，分析了DG以T形接入和专线接入两种形式接入配电网的故障特性，揭示线路两侧保护装置量测的相电流和故障相相间电流随故障位置变化的规律。其次，根据区内外故障时故障特性差异，利用线路两侧保护装置量测的故障相相间电流信息构造新型电流差动保护判据。在此基础上，改进动作量和制动量计算方式，使二者降低通信同步性要求。最后，基于PSCAD仿真平台搭建了10 kV有源配电网模型，验证了所提方法的可靠性和有效性。仿真结果表明，该方法简单易行，在不同DG容量、不同故障位置和不同故障类型的工况下，相较于传统基于正序电流的电流差动保护方法受到DG输出影响更小。 |
| 关键词: 分布式电源 电流差动保护 有源配电网 |
| DOI：10.19783/j.cnki.pspc.243001 |
| 投稿时间：2024-10-21修订日期：2025-08-16 |
| 基金项目:智能电网国家科技重大专项资助(2024ZD0800800)；国网天津市电力公司科技项目资助(电科-研发2024-02) |
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| A new current differential protection method for active distribution networks based on fault-phase interline currents |
| WANG Yang1,ZHAO Ruoyang1,LI Dayong1,HUANG Jiakai2,JIN Yao2,ZHENG Zhiyan3,CHEN Xiaolong3 |
| (1. State Grid Tianjin Electric Power Company, Tianjin 300010, China; 2. Electric Power Research Institute, State Grid
Tianjin Electric Power Company, Tianjin 300392, China; 3. State Key Laboratory of Smart Power Distribution
Equipment and System, Tianjin University, Tianjin 300072, China) |
| Abstract: |
| To address the challenge that traditional protection schemes become unsuitable after distributed generators (DGs) are integrated into distribution networks, a novel current differential protection method is proposed for active distribution networks based on fault-phase interline current. First, considering the control strategies of various DGs during low-voltage ride-through, the fault characteristics of both T-connected and bus-connected DGs are analyzed. The variation patterns of phase currents and fault-phase interline currents measured by protection devices on both ends of the line are revealed with respect to fault location. Second, a new current differential protection criterion is constructed using the interline current information from both line terminals, leveraging the distinction between internal and external faults. On this basis, the calculation methods of the operating and restraining quantities are improved to reduce dependency on communication synchronization. Finally, a 10 kV active distribution network model built in PSCAD validates the reliability and effectiveness of the proposed method. Simulation results demonstrate that the method is simple and practical, and compared with traditional positive-sequence current-based differential protection methods, it is less affected by DG outputs under different DG capacities, fault locations, and fault types. |
| Key words: distributed generator current differential protection active distribution network |
