摘 要
由于常規PID控制器結構簡單、魯棒性強，被廣泛應用于過程控制中，但常規PID不能根據現場的情況進行在線自整定，非線性系統的常規PID控制往往不能獲得較好的控制效果。基于知識和不依賴于精確數學模型的模糊控制給這個問題的解決帶來了新的思路，在很多工業應用中已取得了良好的效果，但模糊控制在進入穩態后存在一定的靜差。在本設計中，將模糊控制器和常規PI控制器結合起來，選取合適的隸屬度函數和制定出模糊控制規則。同時分析輸入變量的量化因子、輸出變量的比例因子在模糊控制系統中對系統性能的影響。最后，將常規PI控制、模糊PI控制通過THJ-2 控制實驗裝置進行實際的液位控制實驗，并用MCGS對系統進行監控。實驗結果表明，采用模糊PI控制的水箱液位，較常規 PI 控制其響應速度快，且較快地達到穩態，從而改善系統的性能。
關鍵字：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.
