利用位置式数字PID 算法提高DFB 激光器驱动电源稳定性

由于分布反馈式(DFB)激光器输出光功率受其激射电流的影响,为了保证其稳定的光功率输出,研制了基于位移式数字PID算法的高稳定性DFB激光器驱动电源。在硬件设计方面,该驱动电源主要由控制器模块、恒流源模块和保护电路模块组成。采用模拟PI深度负反馈环节有效地提高了驱动电流的稳定性。在软件方面,采用位置式数字PID算法,消除了实际驱动电流值与理论值之间的微小差异。利用该驱动电源,对中心波长为1 563.01 nm的DFB激光器做了驱动测试。实验表明,长期稳定性(220 h)优于410-5,中心波长未出现漂移,为其在红外气体检测中提供了优越性能保障。

Stability improvement of DFB laser driving power using digital position PID algorithm

To ensure the stability of output power of Distributed Feedback(DFB) lasers, which was effected by the emitting current, a high stable DFB lasers driver using positional digital PID algorithm was proposed. In terms of hardware design, the aforementioned driver was composed of controller model, constant current model and protection circuit model. The analog Proportion-Integral(PI) deep negative feedback loop was utilized to enhance the stability and precision of driving current effectively. In consider of software design, a positional digital PID algorithm was introduced to eliminate the micro deviation between the real driving current and the theory current value. Using the aforementioned driver, a driving test was performed on a DFB laser with a center wavelength at 1 563.01 nm. Experimental results show that long term(more than 100 h) stability is better than 410-5 and the center wavelength without any shift, which could provide DFBs with excellent performance security for the application of infrared gas detection.