Modeling and Optimal Classical Control of Blending Tank Level System in Cement Plant

Abstract

Optimal material level control in blending tank can be achieved through the use of a PID controller. However, the major challenges of PID controller are high overshoot and steady-state error, prolong settling time, and slow response which practically causes wastages and equipment downtime. Thus, in this work classical techniques were employed to tune PID controllers to achieve optimum performance of the blending tank level control. The mass balance principle was used to model level of the blending tank while Zigler-Nichols (ZN), Chien-Hrones-Reswick (CHR), and Cohen-Coon (CC) techniques were used to tune the PID controller for optimal performance. The performance of the simulated control schemes MATLAB/Simulink were evaluated using rise time, settling time, peak amplitude, and overshoot. The results revealed that the ZN-PID controller gave the lowest rise time of 2.11s, settling time of 14secs, and peak amplitude of 1.04 while the lowest overshoot of 0% was achieved by both CHR and CC-PID. It can be inferred that ZN-PID gives the best way of controlling the level of the blending tank.