摘要
直流偏磁会加剧电流互感器铁芯过饱和磁化,导致在运电流互感器误差值越限,影响电能计量结算的可靠性,甚至可能造成继电保护装置误动。文中分析了直流偏磁工况下电流互感器二次输出波形的特点;提出一种电流互感器直流偏磁在线补偿方法,检测电流互感器二次输出中二次谐波的大小及相位,判断电流互感器直流偏磁的严重程度,调节压控电流源,向互感器补偿绕组注入反向直流电流作为负反馈补偿,减小互感器直流偏磁。
DC magnetic bias can aggravate the core saturation magnetization of current transformer,which may lead the error value of current transformer in operation is out of limit,affect the reliability of electricity metering and settlement,and even cause the misoperation of relay protection device.This paper analyzed the characteristics of the secondary output waveform of current transformer under the condition of DC magnetic bias,this paper proposed a method for online compensation of the DC magnetic bias of current transformer,the magnitude and phase of the second harmonic in the secondary output of the current transformer were detected,the severity of DC magnetic bias of the current transformer was judged,a voltage controlled current source was adjusted to inject reverse DC current into the compensation winding of the transformer as negative feedback compensation.As a result,DC magnetic bias can be alleviated.
作者
胡琛
张竹
陈刚
李敏
杨爱超
李东江
HU Chen;ZHANG Zhu;CHEN Gang;LI Min;YANG Ai-chao;LI Dong-jiang(State Grid Jiangxi Electrical Power Supply Service Management Center,Nanchang 330096,China;School of Electrical Engineering and Automations,Hefei University of Technology,Hefei 230009,China;State Grid Jiangsu Electrical Power Marketing Service Center,Nanjing 211103,China)
出处
《仪表技术与传感器》
CSCD
北大核心
2021年第4期40-44,共5页
Instrument Technique and Sensor
关键词
电流互感器
直流偏磁
在线补偿
负反馈
current transformer
DC magnetic bias
online compensation
negative feedback
