用于单光路TDLAS气体检测的激光器降噪驱动系统设计

Design of laser noise reduction drive system for single optical path TDLAS gas detection

为了去除单光路TDLAS气体检测系统中环境背景和系统本身的噪声干扰,提高系统检测精度,提出了一种激光器降噪驱动方案,并完成了激光器驱动系统设计。选定乙炔气体作为检测对象,首先构建激光器驱动模型,通过时分复用的方式将一路检测激光分为检测段和参考段,结合乙炔气体检测时对检测激光波长的需求给出具体的激光器驱动参数。然后阐述针对该激光器驱动模型的数据处理算法。最后进行电路设计,电路部分首先由主控器控制信号发生单元分别产生所需要的低频信号和高频信号,之后经过信号叠加单元和电压电流转换单元生成激光器驱动信号。经实验测试,结果表明将该激光器驱动系统应用于单光路TDLAS气体检测中能够在一定程度上提高系统检测精度。

In order to remove the noise in the single-optical TDLAS gas detection system, and improve the detec tion accuracy of the system , a laser noise reduction driving scheme is proposed , and the laser driving system design is completed. The acetylene gas is selected as the detection object. Firstly, the laser driving model is constructed. The detection laser is divided into the detectionand the reference segments by time division multiplexing. Combined with the acetylene gas detection, the specific laser driving parameters are given for the requirement of detecting the laser wavelength. A data processing algorithm for the laser driven model is then set forth. Finally, the circuit design is per formed . The circuit part firstly generates the required low frequency signal and high frequency signal by the main con troller control signal generating units, and then generates the laser driving signal through the signal superimposing unit and the voltage-current converting unit. The experimental results show that the laser drive system can improve the sys tem detection accuracy to some extent in the single-optical TDLAS gas detection.