Fractional-Order PI Control of a TITO System Using Particle Swarm Optimization Algorithm

This paper presents the application of fractional order operator to improve the control quality of multivariable systems. The basic ideas of this tuning method are based, in the first place, on the existed tuning methods for setting the parameters of the fractional order PI (FO-PI) controller for λ=l, which means setting the parameters of the integer order PI (IO-PI) controller, the minimum integral criterion by using Particle Swarm Optimization (PSO) algorithm for setting the fractional integration action order λ and the gains of the fractional order PI controller. The integral criterion is formulated to improve the dynamic response of the system, while causing minimum control effort. The Distillation Column, which is a multivariable system with two inputs and two outputs (TITO), in closed loop TITO with decoupling control structure, is analyzed. Simulation results are presented to show the control quality improvement of this proposed FO- PI controller tuning method compared to the IO-PI controller tuned using any existed tuning method.