基于零序电流-电压波形相似度的小电阻接地系统高阻接地故障检测方法  

High-resistance Grounding Fault Detection in Low-resistance Grounding System Based on Similarity Difference of Zero-sequence Current-voltage Waveform

作　　者：肖瑞超 徐涵 Xiao Ruichao;Xu Han(South China University of Technology,Guangzhou 510641,China;Guangzhou Bureau of China Southern Grid EHV Transmission Company,Guangzhou 510670,China)

机构地区：[1]华南理工大学,广州510641 [2]南方电网超高压输电公司广州局,广州510670

出　　处：《机电工程技术》2021年第12期64-67,共4页Mechanical & Electrical Engineering Technology

基　　金：广东省基础与应用基础研究基金项目(编号:2021A1515010631)。

摘　　要：由于配电馈线往往深入负荷中心,所处环境较为复杂,对于小电阻接地系统,现阶段采用的阶段式零序电流保护方案无法有效解决高阻接地故障难以检测的问题。针对此现象,通过分析高阻接地故障时故障线路与健全线路零序电流-电压之间不同的约束关系,进而提出一种基于零序电流电压波形相似度的高阻接地故障检测方法。所提方法通过对各馈线检测点零序电流与母线零序电压进行采样,并通过计算波形相似度相关系数进行故障检测,该方法可显著提高保护耐受过渡电阻的能力。最后,通过PSCAD对典型系统的仿真测试验证了该方法的有效性。Since the distribution feeder is often deep into the load center and the environment is more complicated,for the low-resistance grounding system,the staged zero-sequence current protection scheme adopted at this stage cannot effectively solve the problem of high-resistance grounding fault detection.In response to this phenomenon,the different constraint relationships between the zero sequence current-voltage of the faulty line and the sound line when the high resistance ground fault occurs were analyzed,and then a high resistance ground fault detection method based on the difference in the similarity of the zero sequence current and voltage waveforms was proposed.The proposed method sampled the zero-sequence current and the zero-sequence voltage of the busbar at each feeder detection point,and used the waveform similarity correlation coefficient for fault detection.The method could significantly improve the ability of the protection to withstand the transition resistance.Finally,the simulation test of PSCAD on a typical system verifies the effectiveness of the method.

关 键 词：小电阻接地系统 单相接地故障 高阻接地故障 波形相似度 PSCAD 

分 类 号：TM77[电气工程—电力系统及自动化]