Simplifying controller for process control of systems with large dead time

Abstract

Large dead time is a significant control problem and source of instability for the control loop. A Smith Predictor scheme provides a conventional large dead time compensation leaving other process dynamics to the separate controller. The real long dead time processes, such as heat transfer and flow control systems, typically exhibit long time delays intertwined with other process dynamics. One of the authors, Roman Gorecki, proposed and implemented a new algorithm, based on the principle of simplification of the control system transfer function, to deal with this issue. The concept of this new algorithm, called a Simplifying Controller, is briefly presented. It is followed by the real system example where a heat transfer process control system with use of the Simplifying Controller is described. The Simplifying Controller algorithm offers improved control for large dead-time process control applications.