Comparative Study Of The Pid, Nonlinear Pid, And Fopid Controllers For A Mimo Distillation Column Process

Abstract

Distillation Column Is One Of The Most Important Units In A Chemical Plant. The Distillation Column Is A Multiple Input Multiple Output (MIMO) Process That Means All The Inputs, And Outputs Are Coupled To Each Other. Usually, MIMO System Introduce Challenges To Design Controller Without Decoupling. This Thesis Provides A Comparative Analysis Of Different Control Strategies Used To Control The Top, And Bottom Product Of A Distillation Column By Considering The Effect Of Decoupling. The Wood-Berry (WB) Distillation Column Model Is Considered Which Separates Methanol From Water. The Influence Of The Feed Flow Rate Disturbance Is Considered For This Model. In Order To Reduce Or Eliminate The Cross interaction Between The Inputs And Outputs, It Is Necessary To Design A Decouple Which Enables The Process To Convert Into Two Independent Single Input And Single Output System (SISO). The Proportional-Integral-Derivative (PID), Nonlinear PID (NPID), And Fractional Order PID (FOPID) Controllers Are Designed For The DC Control And Their Parameters Are Optimally Tuned Using A Genetic Algorithm (GA). Performance Evaluation Of The Corresponding Controllers Is Done Using MATLAB/Simulink. The Simulation Result Reveals That The System With Decoupling Reduced Total Error Compared With The System Without Decoupling In Terms Of SP Tracking And Disturbance Rejection.