Chapter 1. Introduction

Objectives of the Chapter

• Introduce the hierarchical approach to process automation and control.

• Introduce the role of model-based control in the overall process control hierarchy.

• Introduce the concepts of model-based control.

• Discuss the outline of the book.

The term model-based control (MBC) is used in this text to mean control systems that explicitly embed a process model in the control algorithm. In particular, we consider control algorithms such as Internal Model Control (IMC) and Model-Predictive Control (MPC) which have found applications in the process industry. Beginning in the early 1970s, the concept of using a predictive model of the process to determine the control actions to be taken has been accepted widely by industrial practitioners. The impetus for this came from the difficulties encountered with decentralized PID (proportional integral derivative) based control approaches that had been the norm in the past. The emergence of computer-based control allowed complex calculations to be performed online. At the same time, the increased cost of energy and raw materials provided greater economic incentives to push the plants to their optimal operating points.