引用本文: | 曾志辉,肖宇.基于变异系数与高阶累积量的小电流接地故障选线[J].电力系统保护与控制,2020,48(13):99-109.[点击复制] |
ZENG Zhihui,XIAO Yu.Small current grounding fault selection based on coefficient of variation and high order cumulant[J].Power System Protection and Control,2020,48(13):99-109[点击复制] |
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摘要: |
针对现有谐振接地系统的暂态量选线法准确性不高的问题,提出一种基于变异系数与高阶累积量的小电流接地故障选线。首先利用变异系数求解零序电流故障分量的初始极性,判断其是线路故障或是母线故障。若为线路故障,则利用变分模态分解对各出线零序电流进行分解,提取出零序电流的直流分量和工频交流分量。最后结合直流分量的高阶累积量和工频交流分量的初始极性构造判据,最终实现双重极性选线。仿真结果表明,该方法不受故障合闸角、过渡电阻的影响。 |
关键词: 谐振接地系统 故障选线 变异系数 高阶累积量 变分模态分解 双重极性 |
DOI:10.19783/j.cnki.pspc.190848 |
投稿时间:2019-07-19修订日期:2019-10-24 |
基金项目:国家自然科学基金项目资助(61703144);河南省科技攻关项目资助(182102210051) |
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Small current grounding fault selection based on coefficient of variation and high order cumulant |
ZENG Zhihui,XIAO Yu |
(School of Electrical Engineering & Automation, Henan Polytechnic University, Jiaozuo 454000, China) |
Abstract: |
In order to solve the problem that the accuracy of transient fault line selection method of resonant earthing system is not high, a small current fault line selection method based on the coefficient of variation and high order cumulant is proposed. First, the initial polarity of the fault component of zero-sequence current is solved using the coefficient of variation. If it is a line fault, the zero-sequence current of each outgoing line is decomposed by means of variational mode decomposition, and the DC component and power-frequency AC component of zero-sequence current are extracted. Finally, the dual polarity selection is realized by combining the high order accumulator of the DC component and the initial polarity construction criterion of the AC component of the power frequency. Simulation results show that this method is not affected by fault closing angle and transition resistance. This work is supported by National Natural Science Foundation of China (No. 61703144) and Science and Technology Key Project of Henan Province (No. 182102210051). |
Key words: resonant grounding system fault line selection coefficient of variation higher order cumulant variational modal decomposition dual polarity |