基于DFB激光器解调技术的光学电流互感器

An optical current transformer based on DFB laser demodulation

针对交流电流的测量,提出了一种基于分布式反馈(DFB)激光器解调技术的光学电流互感器(OCT)。OCT的传感部分运用光纤Bragg光栅(FBG)和超磁致伸缩材料(GMM)作为传感器探头,同时应用DFB激光器对FBG进行解调,实现交流电流的测量。对于这种新型的OCT进行了理论分析和实验研究,实验测得系统传感灵敏度可达到11.822×10-3 nm/A,可获0.63%的满量程精度,线性拟合度达到0.996 2,适用于小电流的高精度检测。

For the measurement of AC current, an optical current transformer （OCT） based on distributed feedback （DFB） demodulation is proposed. The fiber Bragg grating （FBG） and the giant magnetostrictive material （GMM） are used as the sensor probe of the current transformer. By using the DFB laser, we realize the demodulation of fiber grating and the measurement of alternative current. By theoretical analysis and experiment, the sensing sensitivity of the system can reach 11. 822 × 10^-3 nm/A with 0. 63 full scale accuracy, and the linearity-fitted degree is 0. 996 2. So it is suitable for detection of small current with high-precision.