Digital Control Systems

The extraordinary development of microprocessors and their extensive use in control systems in all fields of application has brought about important changes in the design of control systems. Their performance and low cost make them much more capable, in many circumstances, than analog controllers.

In order to take full advantage of this potential, Digital Control Systems demonstrates in detail how to design and implement high-performance model-based controllers combining system identification and control design techniques extensively tested in industrial milieux. The effective use of these techniques is illustrated in the context of various systems including: d.c. motors, flexible transmissions, air heaters, distillation columns and hot-dip galvanizing. Topics covered include:

• essentials of computer-based control systems;


• controller design methods (robust pole placement, long-range-predictive control, state space, digital PID, etc.);


• system identification techniques;


• practical aspects of system identification and digital control.


A number of recent methodological developments in control design and system identification, driven by applications, are presented, including:

• robust digital control design using sensitivity function shaping;


• plant identification in closed loop operation;


• reduction of controller complexity.


The text of Digital Control Systems is enhanced, for practical and tutorial purposes, by the use of software which illustrates the various concepts and algorithms and gives a feeling for the phenomena, discussed. The MATLAB®/Scilab routines used for this purpose can be downloaded from the textbook’s website where additional material for teaching is available (slide presentations of the chapter material, data files for additional laboratory sessions and example files).

Graduate students in courses on digital control will find this text to be most helpful in learning the essential techniques of computer-based control while the wealth of additional material will make the tutor’s tasks of teaching and preparation quicker and easier. The book also provides practising engineers wishing to enhance their skills in this area with efficient and co-ordinated methods for the design and implementation of computer-based controllers.