为了满足红外气体检测对高性能激光器驱动电源的要求, 文中采用PID控制算法, 设计并研制了一款高稳定的DFB激光器驱动电源。其硬件主要包括信号产生模块、压控恒流源模块、电路保护模块, 具备输出电流保护功能。信号产生模块主要通过DDS产生正弦波, 再通过比较器产生方波, 同时采用DA转换技术实现直流波、三角波、锯齿波的输出。控制方案上采用PID算法, 通过深度负反馈控制, 实现高稳定电流输出。利用此驱动电源对中心波长为1 563.09 nm的DFB激光器进行驱动实验。结果表明, 所研制的驱动电源具有输出波形类型、幅度和频率三者数控可调的功能, 电流幅度范围为0~1 A; 正弦、方波频率范围为1 Hz~1 MHz, 三角、锯齿、直流波频率范围为1 Hz~100 Hz, 频率分辨率为1 Hz; 输出电流线性度为99.93%, 长时间输出电流稳定度为0.019 7%。

In order to meet the requirements of infrared gas detection for high performance laser driving power supply, the PID control algorithm was adopted, a high stability DFB laser driving power supply was designed and manufactured. Its hardware mainly included signal generation module, voltage-controlling current source module, circuit protection module. The system had the function of output current protection. In the signal generation module, the sine wave was generated by DDS and then square waves was generated through a comparator. At the same time, DA conversion technique was adopted to realize the output of DC wave, triangular wave and sawtooth wave. Meanwhile, in respect of control scheme, the current high stability was effectively ensured by the use of PID control algorithm and veep negative feedback. With this driver, the driving test was performed on a DFB laser with a center wavelength at 1 563.09 nm. The results show that the driver has the function of the output waveform type, amplitude and frequency can be changed by digital control, the current amplitude ranges from 0 to 1 A and the frequency range is from 1 Hz to 1 MHz. The frequency resolution is 1 Hz. The linearity of the system is 99.93% and the long term output current stability reached 0.019 7%.