摘要
针对变压器差动保护在识别内部故障电流与励磁涌流时的可靠性不高这一问题,提出了基于变压器差流波形密度系数的励磁涌流鉴别算法。利用励磁涌流与故障电流具有不同的正弦相关系数的特点,提出波形密度系数的概念,通过比较变压器各工况下的波形密度系数,理论上可准确识别励磁涌流和故障电流。进一步通过建立仿真模型和实际变压器合闸录波数据进行验证所提算法的可行性和快速性。研究表明,该算法具有判据简单、自带滤波效果、不受非周期分量影响的特点,且能无延时地准确判别励磁涌流与内部故障电流。
Considering that the recognition reliability of internal fault current and magnetizing inrush current by the differential protection of a transformer is relatively lower, a novel algorithm based on waveform density coefficient is proposed to identify magnetizing inrush current. The concept of waveform density coefficient is proposed based on the fact that magnetizing inrush current and fault current have different sinusoid correlation coefficients. Through the comparative analysis of the waveform density coefficients of a transformer under all kinds of operation conditions, it is found that the proposed algorithm can theoretically identify magnetizing inrush current and fault current accurately. Moreover, a simulation model of transformer with the actual closing record wave data are used to verify the applicability and rapidity of the proposed algorithm. It is shown that this algorithm has a simple criterion together with a filtering effect. Additionally, it is not affected by aperiodic components, so it can accurately distinguish magnetizing inrush current from internal fault current without delay.
作者
黄景光
罗亭然
林湘宁
翁汉琍
赵娇娇
HUANG Jingguang LUO Tingran LIN Xiangning WENG Hanli ZHAO Jiaojiao(College of Electrical Engineering and New Energy, China Three Gorges University, Yichang 443002, China School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan 430074, China)
出处
《电力系统及其自动化学报》
CSCD
北大核心
2017年第7期34-40,共7页
Proceedings of the CSU-EPSA
基金
国家自然科学基金资助项目(51477090)
关键词
变压器
差动保护
短路故障
励磁涌流
波形密度系数
transformer
differential protection
short-circuit fault
magnetizing inrush current
waveform density coefficient
