一种改进型光纤压力传感器设计  

Design of an improved fiber optic pressure sensor

作　　者：杨永亮 张羽 李雪佳[1] 于振 关丙火 吴则功 YANG Yongliang;ZHANG Yu;LI Xuejia;YU Zhen;GUAN Binghuo;WU Zegong(Shendong Coal Branch,China Shenhua Energy Company Limited,Yulin 719315,China;Tiandi(Changzhou)Automation Co.,Ltd.,Changzhou 213015,China;Laser Institute,Qilu University of Technology(Shandong Academy of Sciences),Jinan 250104,China)

机构地区：[1]中国神华能源股份有限公司神东煤炭分公司,陕西榆林719315 [2]天地(常州)自动化股份有限公司,江苏常州213015 [3]齐鲁工业大学(山东省科学院)山东省科学院激光研究所,山东济南250104

出　　处：《工矿自动化》2023年第12期12-17,共6页Journal Of Mine Automation

基　　金：国家能源集团科技创新项目(GJNY-21-26-03)。

摘　　要：针对现有光纤压力传感器压力监测范围小、灵敏度低、成本高的问题,设计了一种改进型光纤压力传感器。在悬臂梁粘贴一支应变光纤光栅,悬空一支温度光纤光栅(使其不受应力)。悬臂梁下方的限位罩将弹簧、波纹管压罩、波纹管罩于其内部,限位罩内侧上平面与弹簧上平面接触,弹簧下平面与波纹管压罩接触。当外界压力通过波纹管底部的管道到达波纹管时,高压使其产生轴向的形变,进而压缩弹簧,最终弹簧发生形变,将力传至悬臂梁,改变应变光纤光栅的受力情况。在单层波纹管增加了劲度系数更大的弹簧,以限制外界产生压力时单层波纹管发生形变,使波纹管与弹簧共同传递压力到悬臂梁。实验结果表明:改进后传感器的压力监测量程为0~5 MPa,相比改进前提升5倍,传感器的灵敏度为0.37998 nm/MPa,测量误差在0.02 MPa之内。将改进后的压力传感器应用于某井下输水管道进行验证,结果表明:与高精度电子压力计测量结果相比,该传感器的压力解调误差在0.02 MPa之内。In response to the problems of small pressure monitoring range,low sensitivity,and high cost of existing fiber optic pressure sensors,an improved fiber optic pressure sensor is designed.A strain fiber optic grating is stuck on the cantilever beam and a temperature fiber optic grating is suspended(to make it stress free).The limit cover below the cantilever beam places the spring,corrugated pipe pressure cover,and corrugated pipe cover inside it.The inner upper plane of the limit cover contacts the upper plane of the spring,and the lower plane of the spring contacts the corrugated pipe pressure cover.When external pressure reaches the corrugated pipe through the pipeline at the bottom of the corrugated pipe,the high pressure causes it to undergo axial deformation.The deformation in turn compresses the spring.Finally,the spring undergoes deformation and transmits force to the cantilever beam,changing the stress situation of the strain grating.A spring with a larger stiffness coefficient is added to the single-layer corrugated pipe to limit its deformation when external pressure is generated,allowing the corrugated pipe and spring to jointly transmit pressure to the cantilever beam.The experimental test results show that the improved sensor has a pressure monitoring range of 0-5 MPa,which is 5 times higher than before.The sensitivity of the sensor is 0.37998 nm/MPa,and the measurement error is within 0.02 MPa.The improved pressure sensor is validated in a water pipeline underground.The results show that compared with the measurement results of high-precision electronic pressure gauges,the pressure demodulation error of the sensor is within 0.02 MPa.

关 键 词：光纤压力传感器 应变光纤光栅 温度光纤光栅 单层波纹管 悬梁臂 限位罩 弹簧 

分 类 号：TD326.2[矿业工程—矿井建设]