基于PID控制和遗传算法的半导体激光器温控系统

摘要

In order to achieve the accurate control for the temperature of diode laser, a high precision temperature control system combining PID control and genetic algorithm was designed.The temperature value of diode laser was measured and fed back with the thermistor and photodiode in the system.Meanwhile, thermo electric cooler (TEC) was used as the actuator to control the temperature.Therefore, a double close-loop control system was constructed.The method of optimizing PID parameters in an on-line way with genetic algorithm was proposed.According to the real-time measured error, controller output and rising time, a function was established as the performance index to be optimized.And thus, the parameters for the controller could be dynamically adjusted.The results show that the system can achieve the accurate and stabilized temperature control.The stability and temperature error are 0.027％ and 0.002℃, respectively.Furthermore, the control effect is obviously superior to that of traditional PID control.Therefore, the better application value can be obtained.%为了实现半导体激光器温度的精确控制,设计了将PID控制与遗传算法相结合的高精度温度控制系统.该系统使用热敏电阻与光电二极管进行测量和反馈半导体激光器的温度值,并用热电制冷器作为温控执行器,构成了双闭环控制系统,提出了利用遗传算法在线优化PID参数的方法,根据实时测量偏差、控制器输出和上升时间构建函数作为待优化的性能指标,从而动态调整控制器的参数.结果表明,系统能够实现高精度的温度稳定控制,稳定度达到0.027％,温度偏差为0.002℃,控制效果优于传统的PID控制,具有较好的应用价值.