ABSTRACT
This chapter presents some of the classical approaches to control system analysis and design and extends these to computerized controllers. It outlines the digital control concepts that are implemented in a number of ways. Computerized control offers many benefits over conventional analog control. One of the main tools used in the analysis and design of control systems is the block diagram. A first-order system is one that contains one storage element or capacitor. Cohen and Coon used a first-order with dead time process model to develop a set of initial controller settings. Control systems implemented using digital computers have many advantages over the older analog units. Digital computers can use more complex control schemes to achieve better performance, can include alarms or fail safe procedures, and can log process data for report generation. Controllers can also be designed to adapt to changing process dynamics.
