Selection of the move suppression coefficients in tuning dynamic matrix control

Abstract

Presents an easy-to-use and reliable tuning strategy for unconstrained multivariable dynamic matrix control (DMC). The tuning strategy achieves setpoint tracking with minimal overshoot and modest manipulated input move sizes and is applicable to a broad class of open loop stable processes. The derivation of an analytical expression for the move suppression coefficients, /spl lambda//sup 2//sub i/, and its demonstration in a DMC tuning strategy are some of the significant contributions of this work. The compact form for the analytical expression for /spl lambda//sub i//sup 2/ is derived as a function of first order plus dead time (FOPDT) parameters fit to approximate process dynamics. With tuning parameters computed, DMC is then implemented in the classical fashion using a dynamic matrix formulated from step response coefficients of the actual process. Just as the FOPDT model approximation has proved a valuable tool in tuning rules such as Cohen-Coon, ITAE and IAE for PID implementations, the tuning strategy presented here is significant because it offers an analogous approach for DMC.