摘 要
由于常规PID控制器结构简单、鲁棒性强，被广泛应用于过程控制中，但常规PID不能根据现场的情况进行在线自整定，非线性系统的常规PID控制往往不能获得较好的控制效果。基于知识和不依赖于精确数学模型的模糊控制给这个问题的解决带来了新的思路，在很多工业应用中已取得了良好的效果，但模糊控制在进入稳态后存在一定的静差。在本设计中，将模糊控制器和常规PI控制器结合起来，选取合适的隶属度函数和制定出模糊控制规则。同时分析输入变量的量化因子、输出变量的比例因子在模糊控制系统中对系统性能的影响。最后，将常规PI控制、模糊PI控制通过THJ-2 控制实验装置进行实际的液位控制实验，并用MCGS对系统进行监控。实验结果表明，采用模糊PI控制的水箱液位，较常规 PI 控制其响应速度快，且较快地达到稳态，从而改善系统的性能。
关键字：模糊控制；PLC；液位The PLC realization of optimize PID parameter by the fuzzy algorithm and configuration design
Abstract
PID controller has simple structure and good robustness and it is widely used in process control systems. Conventional PID can not regulate itself according to the changes on-line, so the conventional PID control of nonlinear systems can not get satisfying results. Fuzzy control, which is based on knowledge and independent of accurate math model, brings a new way of resolving this problem. Fuzzy control has got good effect in many industrial applications, but it has steady error. In this design, combining fuzzy controller with PID controller to Choose suitable membership function and the fuzzy control rule, and analyze the affect to the system, which is bring by quantum gene of input-variable and proportion gene of output-variable. Finally, the general PID controller and fuzzy PID controller are used in liquid-level control experiment by the control experiment equipment of THJ-2, and monitoring the control system by MCGS. The results show that fuzzy-PID controller has quicker response and quicker to get steady state and also can improve the system performance.
