南方电网技术2024，Vol.18Issue(10)：107-115,9.DOI:10.13648/j.cnki.issn1674-0629.2024.10.011
基于功率因数角双端测量的配电网单相接地故障检测新方法
New Method of Single-Phase Grounding Fault Detection in Distribution Network Based on Power Factor Angle Two-Terminal Measurement
摘要
Abstract
In order to solve the problem that single-phase grounding fault detection(especially high-resistance grounding fault)in traditional distribution network is affected by weak fault characteristics and difficult to detect,this paper proposes a new detection method for single-phase grounding fault detection in eutral point ungrounded distribution network based on two-terminal measure-ment of power factor angle from the perspective that the power of distribution network system will change significantly before and after the fault.The two voltage transformers connected with the neutral point inject controllable current signals into the neutral point and measure the return voltage signals,so as to accurately measure the active and reactive power of the distribution network at the cur-rent operating state,and then obtain the power factor angle of the system.Combined with the power factor angle of the distribution network under normal operation,the ratio coefficient of power factor angle before and after the system failure is measured in real time.Based on the comparison between the ratio coefficient and the ratio threshold coefficient,the sensitive detection of high resistance grounding fault is realized.The smart application of dual voltage transformer eliminates the measurement error caused by internal resistance and detuning resistance of the transformer in principle and greatly improves the effective detection range of high resistance grounding fault in distribution network.The proposed method is verified by setting up a 10 kV neutral point ungrounded distribution network in the simulation environment of PSCAD/EMTDC.Different types of high resistance grounding faults are simulated to verify the proposed method.The simulation results show that the proposed method can detect high resistance grounding faults reliably,and the detection range is up to 20 kΩ.关键词
双电压互感器/注入信号/单相接地故障/功率因数角/配电网Key words
dual voltage transformers/injection signal/single-phase grouding fault/power factor angle/distribution network分类
信息技术与安全科学引用本文复制引用
欧阳剑,白浩,杨海军,杨乾,刘红文,叶升言..基于功率因数角双端测量的配电网单相接地故障检测新方法[J].南方电网技术,2024,18(10):107-115,9.基金项目
国家重点研发计划资助项目(2017YFB0902902) （2017YFB0902902）
中国南方电网有限责任公司科技项目(YNKJXM20210175). Supported by the National Key Research and Development Program of China(2017YFB0902902) （YNKJXM20210175）
the Science and Technology Project of China Southern Power Grid Co.,Ltd.(YNKJXM20210175). （YNKJXM20210175）
