Design of IFLC for a Three Tank System

Conventional PID controllers have been widely applied in industrial process control for about half a century because of their simple structure and convenience of implementation. The implementation of PID controllers needs proper tuning of proportional gains, integral gains, and derivative gains of the controllers. Among the existing gain tuning techniques, the method proposed by Ziegler and Nichols is probably the bestknown and most popular. However, a conventional PID controller may have poor control performance, when it is used for controlling non-linear and complex processes, for which there are no precise mathematical models available. It is well known that the conventional controllers are suitable to control linear processes and their design is based on the exact mathematical model. In this research work, to improve the performances of PID controller, a FLC is integrated with the PID controller (IFLC) and IFLC design is formulated as an optimization problem and GA, PSO and Modified PSO algorithms are applied to design the parameters of IFLC. The evolutionary IFLC is applied to control a three tank system and the performances are evaluated.