摘要
本文提出了一种基于偏振检测原理,采用Bi4Ge3O12(BGO)晶体的磁光式冲击电流传感器,可以测量幅值范围10 kA到90 kA的8/20μs冲击电流。由于冲击电流的持续时间极短,光源功率漂移对测量的干扰可以忽略,偏振检测结构可以保证测量结果的正确性。由于BGO晶体具有维尔德常数大的突出优点,传感器可以获得较高的测量灵敏度。利用小波分解法,并以信噪比(SNR)和平滑度(SR)作为去噪结果的评价标准,确定了合适的小波函数(Daubechies Db7)和分解层数(5层),有效地去除了测量结果中的干扰噪声。此电流传感器的灵敏度达到0.262 2°/kA,具有较好的线性度,且冲击电流幅值的测量误差控制在±5%以内。本文所提出的电流传感器具有结构简单、性能可靠的优点,适用于雷电流测试、核物理实验和高功率脉冲激光研究等恶劣环境下的冲击电流测量。
A magneto-optical current sensor based on Bi4Ge3O12(BGO) crystal is proposed in this paper.The sensor which adapts polarimetric detection scheme is used to measure 8/20 μs impulse current whose amplitude is in the range from 10 kA to 90 kA. Compared with the variation of light source intensity,impulse current duration time is very short and the measurement disturbance caused by light source is negligible.Thus,polarimetric current sensing configuration scheme can guarantee the correctness of measurement results. Since BGO crystal has the prominent advantage of large Verdet constant,the proposed current sensor can obtain high measurement sensitivity. In order to remove noise effectively,wavelet decomposition method is used as specific denoising technique. According to the signal-to-noise ratio(SNR) and smoothness(SR) of denoised signals,Db7 and decomposition level of 5 are chosen as appropriate wavelet function and decomposition level,respectively.Experimental results reveal that sensor has a good linear sensitivity of 0.262 2°/kA and the measurement error of impulse current peak value is within ±5%.The proposed sensor has the advantage of simple and reliable structure,showing a potential application in impulse current measurement in harsh environment including lightning current test,nuclear physics experiment and high-power laser pulse research.
作者
王良江
黄怿
邓传鲁
胡程勇
王廷云
WANG Liang-jiang;HUANG Yi;DENG Chuan-lu;HU Cheng-yong;WXNG Ting-yun(Key Laboratory of Specialty Fiber Optics and Optical Access Net works,Joint International Research Laboratory of Specialty Fiber Optics and Advanced Communication,Shanghai Institute for Advanced Communication and Data Science,Shanghai University,Shanghai 200444,China)
出处
《光电子．激光》
EI
CAS
CSCD
北大核心
2019年第9期917-923,共7页
Journal of Optoelectronics·Laser
基金
国家自然科学基金(61475096)资助项目
关键词
光学电流传感器
法拉第效应
冲击电流测量
小波分解法去噪
optical current sensor
Faraday effect
impulse current measurement
wavelet decomposition denoising
