Shaping time-domain response with discrete controllers

GIOVANINI L, MARCHETTI J

Industrial & Engineering Chemical Research

ACS Publications

Año: 1999 vol. 38 p. 4777 - 4789

1520-5045

A model-based design and tuning method for discrete controllers for single-input-single-output systems is presented in this article. It stresses the possibility of specifying the desired closed-loop behavior by using a set of time-domain conditions defining the performance that is desirablein the controlled output. The problem formulation is developed in the time domain since this is the domain where many important and different design conditions can be visualized and written in an easy mathematical form, particularly for most continuous chemical processes. This approach allows shaping the time-domain closed-loop response by one or more constraints representing the limits of minimum performance desired when specific changes on either the setpoint or theload disturbance are expected. Model uncertainties caused by slow  time-variant or nonlinear systems can also be accounted for, guaranteeing robust performance and stability of the closed- loop system.