研制开发了一种基于TMS320F28069嵌入式DSP控制模板的高精度数字温度控制系统,该系统结合变速积分PID控制算法,利用高分辨率脉宽调制(HRPWM)技术,控制热电制冷器(TEC)的驱动电流。针对热敏电阻在高温和低温时温度系数的区别,采用了不同方式的温度检测电路。该系统同时含有三路独立的常温控温模块,在10℃~40℃温控精度为±0.0045℃,一路高温控温模块,在120℃~160℃温控精度为±0.005℃。将该系统用于控制全固态连续单频绿光激光器,在输出功率高达11.07 W时功率波动仅为±0.33%。
A high-precision digital temperature-control system(HPDTCS) based on TMS320F28069 for all-solidstate single-frequency green laser is designed and built. The speed-change integral PID control algorithm and the high-resolution pulse width modulation(HRPWM) technology are utilized in this system to control the drive current of the thermoelectric cooler(TEC). Depending on the difference of the temperature efficient of the thermistor under higher and lower temperature, the different temperature detection circuits are applied. The HPDTCS consists of three lower(10 ℃ to 40 ℃) and a higher(120 ℃ to 160 ℃) temperature- control modules with precisions of± 0.0045 ℃ and ±0.005 ℃, respectively. Applying the HPDTCS to control an all-solid-state single-frequency green laser, the power fluctuation of ±0.33% is achieved at the output power of 11.07 W.