分布式光纤传感器测量数据可靠性分析方法

Reliability analysis method of measurement data for distributed optical fiber sensors

分析了分布式光纤传感器测量结果的可靠性,提出从应变系数和温度系数标定到分布式光纤传感器物理量测量以及结果评价的方法,设计了分布式光纤传感器的应变系数和温度系数标定装置,同时分析了应变标定装置的不确定度来源,采用基于光频域反射技术的分布式光纤解调仪进行了实验验证。应变标定范围为-5000με~5000με,温度标定范围为20℃~50℃,第一次测量得到应变系数和温度系数分别为:-6.6775με/GHz和-0.5921℃/GHz。使用获得的应变系数和温度系数再次测量,得到在测量范围内,应变测量相对误差为1%,温度测量相对误差为2%,满足工程应用要求。上述结果表明,设计、发展的数据标定及分析方法可用于分布式光纤传感器应变系数和温度系数的标定。

The reliability of the measurement results of distributed optical fiber sensors is analyzed.The methods from strain coefficient and temperature coefficient calibration to physical quantity measurement and result evaluation for distributed optical fiber sensors are proposed.The strain coefficient and temperature coefficient calibration devices of distributed optical fiber sensors are designed,and the sources of uncertainty of the strain calibration device are analyzed.Experimental validation is performed using a distributed fiber demodulator based on optical frequency domain reflection technology.The strain calibration range is-5000με~5000με,and the temperature calibration range is 20℃~50℃.The strain coefficient and temperature coefficient are-6.6775με/GHz and-0.5921℃/GHz,respectively.Furthermore,the measurements are carried out again using the obtained strain coefficient and temperature coefficient.It is found that within the measurement range,the relative error of strain measurement is 1%,and the relative error of temperature measurement is 2%,which can meet the engineering application requirements.The results show that the data calibration and analysis methods designed and developed can be used to calibrate the strain coefficient and temperature coefficient of distributed fiber optic sensors.