新型雷电流测量用无磁芯电流传感器的研究

Research on a New Type of Non-magnetic Core Current Sensor for Lightning Current Measurement

电力系统遭受雷击导致的跳闸事故是当前电力系统运行中的主要故障之一,对雷电流进行精确的测量是研究雷电特性以及分析雷击跳闸事故的重要路径和前提。针对传统的电磁式电流互感器频带窄、易饱和、难以对雷电流进行有效测量等特点,本文研制了一种新型雷电流测量用无磁芯电流传感器。该传感器通过将6个传感器均匀安装在一个圆形印刷电路板上,搭建了用于测量雷电流的圆形阵列,并利用一种基于对小部分磁场测量的数字处理算法,减小了圆形阵列的串扰误差,设计并研制电流传感器样机测量结果与实际电流相近,证明了该无磁芯传感器具有频带宽、灵敏度高、线性度好、抗饱和能力强、测量电流范围宽等优点。

The trip accident caused by lightning stroke in power system is one of the main faults in power system operation.Accurate measurement of lightning current is an important path and premise to study lightning characteristics and analyze lightning trip accidents.In view of the characteristics of traditional electromagnetic current transformer,such as narrow frequency band,easy saturation and difficult to effectively measure lightning current,a new coreless current sensor for lightning current measurement is developed in this paper.By evenly installing six sensors on a circular printed circuit board,a circular array for measuring lightning current is built,and a digital processing algorithm based on measuring a small part of magnetic field is used to reduce the crosstalk error of the circular array.A prototype of current sensor is designed and developed,and the measurement results are close to the actual current.It is proved that the coreless sensor has the advantages of wide frequency band,high sensitivity,good linearity,strong anti saturation ability and wide measurement current range.