Controlling the Liquid Level of Hopper Shape NonlinearTank System using PID & MPC Controller.

This article comprises of modeling, design, and analytical results of conventional and advanced controllers like P, PI, PID, and MPC algorithm for nonlinear tank system are considered to achieve desired set point tracking in level measurement. Hopper shape tank system is considered as non-linear, which comprises of numerous influence variables (output, manipulated, and input variables). Most of the processes used in the petrochemical, process, and pharmaceutical industries are non-linear. Due to the nonlinear cross-section at the hopper tank, measurement of level plays a vital role in these industries. The authors have designed four different controllers for desired level tracking and simulated in MATLAB software to achieve the closed-loop and open-loop performance analysis of the processing system. Autotune and Ziegler Nicholas method based PID algorithm has been used by some authors to find the tuning parameters of P, PI, and PID Controllers for achieving the desired set point. MATLAB Simulink model is used for the design and implementation of the controllers for a nonlinear process tank system and to obtain the rise time, overshoot, settling time, and steady-state error that indicates the performance of the process with the controller. The advanced control algorithms like MPC with linear constraints is designed for level tracking of hoper tank system within desired specified limits. Finally, the performance analysis is compared with conventional controllers like P, PI, and PID. MPC with linear constraints will be able to track the level of the hoper tank system in less time and a reduced number of control and prediction horizons. [ABSTRACT FROM AUTHOR]