| 引用本文: | 李 军,朱劲涛,张玉琼,等.基于双电流突变量比值的含光伏电源低压配电网触电故障检测和定位方法[J].电力系统保护与控制,2025,53(18):97-108. |
| LI Jun,ZHU Jintao,ZHANG Yuqiong,et al.Electric shock fault detection and positioning method for low-voltage distribution networks with PV power supply based on the ratio of dual-current mutant amount[J].Power System Protection and Control,2025,53(18):97-108 |
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| 摘要: |
| 针对分布式光伏接入的低压配电网中，剩余电流波形复杂、幅值随机多变，现有剩余电流保护装置频繁误动作、难以投入使用的问题，提出剩余电流与重复接地点电流突变量的比值结合剩余电流动作整定值的双重判据。首先，分析含光伏电源的TN-C-S系统发生触电故障时、重复接地点和负荷数量逐渐增加的情况下剩余电流的组成成分以及变化情况，提出剩余电流与重复接地点电流突变量的比值的阈值作为触电判据。接着分析重复接地点对触电电流分流的影响，提出利用比值的平均值大小定位故障区段。通过仿真验证，所提判据可以准确检测触电故障，抗干扰能力强，有效改善保护装置的误动作问题，实现不同故障位置下的故障区段准确定位。 |
| 关键词: 光伏电源 低压配电网 剩余电流 生物触电 故障定位 |
| DOI：10.19783/j.cnki.pspc.241577 |
| 分类号: |
| 基金项目:江苏省科技创新专项基金重点项目资助(BE2022003) |
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| Electric shock fault detection and positioning method for low-voltage distribution networks with PV power supply based on the ratio of dual-current mutant amount |
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LI Jun, ZHU Jintao, ZHANG Yuqiong, LÜ Ganyun, LIU Ketian, HUANG Jiawei
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School of Electrical Power Engineering, School of SHEN Guorong, Nanjing Institute of Technology, Nanjing 210000, China
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| Abstract: |
| In low-voltage distribution networks with distributed photovoltaic (PV) integration, residual current waveforms are complex and their amplitudes vary randomly. This often leads to frequent maloperation of existing residual current protection devices, making them difficult to apply effectively. To address this issue, a dual-criterion approach is proposed, combining the ratio of the mutation values of residual current and repeated grounding current with the residual current setting threshold. First, the composition and variation of residual current in a TN-C-S system with PV power supply under electric shock faults are analyzed, considering increasing numbers of repeated grounding points and loads. Based on this, a threshold for the ratio of the residual current and repeated grounding current mutation is established as fault detection criterion. Then, the influence of repeated grounding points on the diversion of electric shock current is examined, and a method for fault location is proposed using the average value of the mutation ratio. Simulation results verify that the proposed criteria can accurately detect electric shock faults, demonstrate strong anti-interference capability, effectively reduce maloperation of protection devices, and achieve accurate positioning of fault sections under different fault positions. |
| Key words: PV power supply low-voltage distribution network residual current human electric shock fault location |
