Application of fuzzy self-tuning PID control to water level control system

Considering the characteristics of long lag,nonlinearity and variation with time in the process of level control,a fuzzy self-tuning PID control algorithm is put forward. The water level system of a double-tank is studied in this paper and the mathematical model is constructed through step response test. Membership function and fuzzy PID control rules are selected to design a fuzzy self-tuning PID controller. Finally,the comparison between fuzzy self-tuning PID control algorithm and conventional PID control algorithm is conducted through the MATLAB simulation. The simulation results demonstrated that,fuzzy self-tuning PID control has more advantages over conventional PID control on small overshoot and short setting time.