| 引用本文: | 李晓波,彭超红,袁璐健,等.融合两阶段暂态信息的灵活接地系统高阻接地故障选线研究[J].电力系统保护与控制,2025,53(23):75-89.[点击复制] |
| LI Xiaobo,PENG Chaohong,YUAN Lujian,et al.Research on fault line selection method for high-resistance grounding faults in flexible grounding systems based on integration of two-stage transient information[J].Power System Protection and Control,2025,53(23):75-89[点击复制] |
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| 摘要: |
| 灵活接地系统兼具谐振接地系统与小电阻接地系统的优点，但其采用零序过电流保护，存在耐过渡电阻能力低的问题。对此，提出了综合利用灵活接地系统中小电阻投入阶段与消弧线圈补偿阶段暂态信息的选线方法。首先分析了消弧线圈补偿阶段和小电阻投入阶段各线路的零序暂态电流，发现在消弧线圈补偿阶段故障线路暂态零序电流比非故障线路多了一个流经过渡电阻的电流分量，而在小电阻投入阶段各线路的暂态零序电流表达式相同。其次根据小电阻投入阶段的暂态零序电流计算各线路对地电容比值，利用该比值对消弧线圈补偿阶段各条线路的暂态零序电流做差，发现故障线路与非故障线路暂态零序电流之差为流经过渡电阻的电流，非故障线路间的暂态零序电流之差为0。再次通过构建零序电流差值矩阵，比较矩阵各行各列元素实现故障选线。最后在PSCAD/EMTDC和低压实验平台验证了所提方法的正确性和有效性。 |
| 关键词: 灵活接地 高阻接地故障 消弧线圈补偿阶段 小电阻投入阶段 暂态零序电流 |
| DOI：10.19783/j.cnki.pspc.250003 |
| 投稿时间：2025-01-02修订日期：2025-06-06 |
| 基金项目:国家自然科学基金面上项目资助(52077215) |
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| Research on fault line selection method for high-resistance grounding faults in flexible grounding systems based on integration of two-stage transient information |
| LI Xiaobo,PENG Chaohong,YUAN Lujian,ZHANG Shile,ZHOU Jun,LIU Jianhua,LIANG Rui |
| (School of Electrical Engineering, China University of Mining and Technology, Xuzhou 221116, China) |
| Abstract: |
| Flexible grounding systems combine the advantages of resonant grounding and low-resistance grounding systems. However, when using zero-sequence overcurrent protection, they exhibit poor tolerance to transition resistance. To address this issue, a fault line selection method is proposed to comprehensively utilize transient information in the low-resistance input stage and arcing coil compensation stage in flexible grounding systems. First, the zero-sequence transient currents of each line during the arc suppression coil compensation stage and the low-resistance input stage are analyzed. It is found that, during the arc suppression coil compensation stage, the faulted line has an additional current component passing through the transitional resistance compared to the healthy lines, while the expressions of transient zero-sequence currents of each line are the same during the low-resistance input stage. Next, by calculating the line-to-ground capacitance ratio based on the transient zero-sequence currents during the low-resistance input stage, the difference between the transient zero-sequence currents of each line during the arc suppression coil compensation stage is obtained using this ratio. The difference of transient zero-sequence currents between the faulted and healthy lines is the current passing through the transitional resistance, while that among the healthy lines is zero. Furthermore, by constructing a matrix of zero-sequence current difference, the fault selection is achieved by comparing the elements of each row and column of the matrix. Finally, the correctness and effectiveness of the proposed method are validated in PSCAD/EMTDC and a low-voltage experimental platform. |
| Key words: flexible grounding high-resistance grounding fault arc suppression coil compensation stage low-resistance input stage transient zero-sequence current |
