基于磁光晶体和光纤光栅的反射式磁场传感器  

Reflective Magnetic Field Sensor Based on Magneto-Optical Crystal and Fiber Bragg Grating

作　　者：侯越 周湶[1] 欧阳希 陈伟根[1] 董润榆 Hou Yue;Zhou Quan;Ouyang Xi;Chen Weigen;Dong Runyu(State Key Laboratory of Power Transmission Equipment Technology,Chongqing University,Chongqing 400044,China)

机构地区：[1]重庆大学输变电装备技术全国重点实验室,重庆400044

出　　处：《光学学报》2024年第11期272-282,共11页Acta Optica Sinica

基　　金：国家自然科学基金联合基金(U186660004);南瑞集团有限公司合作项目(0664-2160SUMEC9NR1045)。

摘　　要：设计了一种基于稀土磁光晶体和光纤光栅的宽温区反射式光纤磁场传感器,其中,选用Bi∶YIG作为磁场传感元件、光纤布拉格光栅(FBG)作为温度补偿元件与反射器件(替代传统反射镜),建立了该结构的理论传感模型以支撑磁场-温度双参数感知,设计了磁场解调方法及其温度补偿法,以实现去温度干扰下磁场的精准测量。经测试,该磁场传感器在0.02~30 mT内直流磁场下的灵敏度为0.034 rad/mT,线性相关系数高达0.9995;在50 Hz~10 kHz正弦交流信号下具有良好的动态响应能力;同时,传感器的温度特性测试证明,本文所设计的温度补偿法可在一定程度上减小环境温度对磁场传感性能的影响,且不受光源波动的影响。本文提出的磁场传感器具有集成度高、系统结构简单、体积小和灵敏度高等优点,可满足电力设备中特殊场景下的磁场传感需求。Objective The power system is a key hub in China’s power transmission network,and includes many important power equipment such as transformers,distribution cables,and motors.The safety and stability of power equipment is an important guarantee for the reliable operation of the power system.Smart grid sensor technology as a key part of the power Internet of Things continuously develops and gradually covers a variety of applications in power industry perception scenes.Traditional magnetic field sensors are susceptible to electromagnetic interference and magnetic saturation,small dynamic measurement range,slow dynamic response,and insufficient insulation,which cannot meet the demand for real-time accurate monitoring of magnetic field in the emerging smart grid.Therefore,the continuous improvement and development of magnetic field sensing and measurement technology matching the smart grid is crucial for realizing the intelligent control of the power grid and ensuring the safe and stable operation of the power grid.The magneto-optical(MO)crystal fiber-optic magnetic field sensor features small size,sound insulation,and high sensitivity compared with other fiber optic sensors,and the Verdet constant of the MO crystal can be improved by adding rare-earth elements.Thus,it has broad engineering application prospects,but the temperature sensitivity will result in the crosstalk between the magnetic field and temperature.Methods We theoretically analyze the nonlinear effects of temperature on the magnetic field measurement of the sensor and design a reflective integrated fiber optic magnetic field sensor based on the common optical path structure of rare-earth MO crystals and the fiber Bragg grating(FBG)to solve the above problems.In the sensor,Bi∶YIG is selected as the magnetic field sensing element,and FBGs are an alternative to conventional mirrors with their high-reflectivity and temperature-sensitive characteristics.The theoretical sensing model of the structure is built by adopting the Jones matrix to support the m

关 键 词：光纤光学 磁光晶体 反射式结构 光纤布拉格光栅 温度-磁场双参数解调 温度补偿法 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]