针对时分复用光纤光栅(TDM-FBG)传感阵列中使用的分布反馈(DFB)激光器高波长稳定度的要求,设计了一个高精度的DFB温控方案,包括温度测量与设定、热敏电阻线性化、PID补偿回路、H桥驱动、温度电压采集与显示等。使用DFB内置的热敏电阻和半导体制冷器(TEC)对温控电路进行了测试,其精度在180s内达到±0.04℃,温控后激光器温度变化引起的应变测量误差为±3.4με左右,满足TDM-FBG传感阵列的要求。
In order to meet high wavelength stability of DFB in time division multiplexing fiber Bragg grating(TDM-FBG)sensing array,temperature control circuits of DFB are designed,including temperature measurement and set circuits,thermistor linearization,H-bridge driving circuits,PID compensation network,temperature voltage sampling circuits and display circuits.The parameters of DFB ’ s temperature control circuits are tested by using the built-in thermistor and TEC,its accuracy can reach ±0.04 ℃ within 180 seconds.This result shows that the strain measurement error from laser ’ s temperature drift will be ±3.4με after temperature control.