Solution of some model predictive control problems using slopes between unconstrained and constrained optimums

At times, the number of controlled Variables equals the number of manipulated variables and the objective of the control system is to minimize the difference in the desired and predicted output trajectories subject only to constraints on the manipulated variables. If a simplified model predictive control algorithm is used for such applications, then solution to the optimization problem can be obtained by using the slopes between the unconstrained and constrained optimums. The solution procedure is described for a two-input-two-output case. A comparison with a linear programming (LP) formulation showed that the computational time for the proposed solution was about 35 times less than the time for the LP solution. Copyright (C) 1999 John Wiley & Sons, Ltd.