一种自校准光纤珐珀动态应变检测系统的实验研究

针对工程中光纤珐珀传感器的工作点容易偏离线性工作区而使解调系统无法正常工作的实际问题,设计了一种可实现自动校准工作点的动态应变检测系统。该系统利用数字信号处理器控制可调珐珀滤波器自动输出波长满足工作点要求的窄带光,同时还通过软件校准的办法消除了因光源的不稳定、系统老化等缓变因素引起的信号波动对测量结果的影响。实验结果表明该动态应变检测系统能完成工作点自动校准,并且在500με范围内线性度可达99．79％,实验分辨率约为±0．5με。

Experimental Study of Fiber Fabry-Perot Dynamic Strain Detection System with Self-Calibration

Because the operating point of the fiber Fabry-Perot sensor is easily affected by the surrounding condition, such as temperature and pressure, in the practical applications, a dynamic strain measurement system that can automatically calibrate its operating point is reported in this paper. In this system, the wavelength of the narrow-bandwidth optical source from the Fabry-Perot tunable filter and broadband source could be adjusted by the digital signal processor （DSP） after the operating point is changed. Moreover, the influence of the factors such as the instability of the light source and the slowly unaecelerated aging of the system, can be eliminated or decreased by the auto-calibration method based on the software. The experimental results show that the operating point of this system can be automatically calibrated. In the strain range of 500με, the linearity is up to 99.79%, and the resolution of ＋0. 5με is achieved. Such a system is of great significance in practical engineering applications.