基于PLC的环境模拟系统温度控制算法的研究与实现

针对环境模拟试验温度控制系统中被控对象存在的非线性、时滞等特点,本文采用区间限幅PID控制算法和模糊PID控制算法对传统控制方法进行了改进。首先为了解决模拟量三通粗调阀调节缓慢的缺点,建立了区间限幅PID控制算法的控制规则表,并将其在PLC中实现。其次提出用模糊PID控制算法来解决电加热器的非线性、大时滞性问题,并结合实际控制经验建立了模糊控制规则表,然后将模糊PID控制算法在PLC中进行实现。最后将限幅PID和模糊PID控制算法应用于某大型环境模拟试验控制系统,实验结果表明利用改进算法对温度控制具有良好的稳定性及精确度。

Research and Implementation of Temperature Control Algorithm for Environment Simulation System Base on PLC

In view of nonliner,time-delay of controlled object in a temperature control system for environment simulation test, theSrange limit PIDScontrol algorithm and fuzzy PID control algorithm is adopted to improve the traditional control method in this paper. Firstly, in order to solve the disadvantage of tardiness for Analog tee coarse adjustment valve,controlSregulation table of theSrange limit PIDScontrol algorithmSis established, then the algorithm is implemented in PLC.Then the method of using fuzzy PID control algorithm to solve nonliner, time-delay of electrical heater is proposed, the fuzzy controlSregulation table is established after combining with the actual control experience,thenthe fuzzy PID control algorithm is implemented in PLC. Finally, theSrange limit PIDScontrol algorithm and fuzzy PID control algorithm is applied to a large environmental simulation test control system,the experimental results show that it has a good stability and accuracy.