基于遗传算法优化PID控制器参数的环境测试舱温湿度控制

Temperature and humidity control for environmental test chamber based on genetic algorithm optimized parameters of PID controller

大容积环境测试舱内温湿度控制系统具有非线性、时变性和耦合性的特点,传统的比例积分微分(Proportion integral differential,PID)控制器参数整定方法不能满足环境测试舱温湿度控制的要求。只有获得PID控制器的最优参数才能实现环境测试舱温湿度的优化控制。该文提出一种遗传算法(Genetic algorithm,GA)优化PID控制器参数的控制算法—GA-PID。首先通过预估解耦方法对温湿度解耦,然后将目标函数作为控制器的评估值,通过遗传算法的选择、交叉、变异、迭代功能获得PID控制器参数的最优解,以弥补常规PID算法在环境测试舱温湿度控制系统中的不足。通过MATLAB进行了仿真实验,实验结果表明预估解耦可有效地对温湿度进行解耦,提出的GA-PID控制算法可实现快速、准确以及稳定的环境测试舱温湿度控制,具有更好的控制性能。

The control system of temperature and humidity in the big volume environmental test chamber has the characteristics of nonlinearity, time-varying and coupling. The traditional parameter tuning method of proportion integral differential （ PID） can not meet the requirements of the temperature and humidity control in the environmental test chamber. The intelligent control of the temperature andhumidity of the environmental test chamber can be realized only by obtaining the optimal parameters of the PID controller. This paper proposes a control algorithm based on genetic algorithm （ GA） optimized parameters of PID controller, which is named as GA-PID. Firstly, the temperature and humidity is decoupled by the predictive decoupling method. The objective function is used as the evaluation value of the controller, and the optimal solution of PID control parameters can be obtained through the selection, crossover and mutation of genetic algorithm. The proposed control algorithm can make up the deficiency of conventional PID in temperature and humidity control system. Simulation experiment is carried out by MATLAB. The results show that the temperature and humidity can be effectively decoupled, the GA-PID control algorithm can achieve a more rapid, accurate and stable temperature and humidity control. The proposed control system has better control performance.