Antiwindup PID controller design of TITO system based on ideal and inverted decoupling

Abstract

In the present paper a simple anti-reset windup solution is derived for TITO PID control based on the ideal decoupler. Difficult examples are used to demonstrate performance of the proposed anti-reset windup TITO controller. The first example is the model of a typical industrial process, with significant multivariable interactions, a non-self regulatory nature, non-minimum-phase behavior and with integral action in the decoupler. The second example is a stable process with high relative gain array RGA of 13.7 in the nominal operating regime and significant multiple dead-times. An anti-reset windup solution is proposed also for inverted decoupling. Closed-loop system responses, obtained by antiwindup implementations based on the ideal and inverted decoupling, are compared on a stable process with an RHP zero and multiple time delays.