A PRACTICAL METHOD OF REMOVING ILL-CONDITIONING IN INDUSTRIAL CONSTRAINED PREDICTIVE CONTROL

At any control execution of large scale Dynamic Matrix Control [DMC](T M), the process may require excessive input movements. This problem ar ises from the ill-conditioned internal models of the predictive contro ller. In this paper, a practical method of removing the ill-conditioni ng is developed by making the best use of the Singular value Analysis (SVA) and the characteristic of LP optimizer in DMC. The proposed meth od is applied to an industrial ammonia plant, where non-square (25 con trolled - 12 manipulated variables) DMC controller is installed By red esigning some internal models which are indicated by the method the re sulting controller can suppress the excessive input movements and impr ove the control performance.