Implementation Issues in Nonlinear Predictive Control

Nonlinear predictive control is an effective strategy for controlling nonlinear processes with constaints and time delays. In this paper a number of important issues involving the implementation of nonlinear predictive control are addressed. The most important issue is the determination of the state variable initial conditions for the prediction optimization at each time step. As long as the initial conditions are accurate, a number of methods used for the model prediction phase yield nearly identical performance results. Relative computation time for the various techniques are compared using an exothermic CSTR example.