ABSTRACT
This chapter introduces the principles involved in digital control systems and discusses the issues that arise in the design and implementation of digital controllers. It proceeds by covering sampled-data systems, discrete-time systems, and the design of discrete time controllers. The chapter discusses the principles of the sample-and-hold process, which is divided into two parts, the "sampler" and the "hold." It should be recalled that although under digital control one deals with discrete signals, the ultimate goal is to recover the continuous-time (analog) signals that are natural using the D/A converter. The chapter extends the ideas presented under the sampling process section to generate difference equations from the continuous-time differential equations giving the discrete form of describing the dynamics of the system. It explores the description of the transfer function using both the -transform and the time shift operator q. The chapter explains the methods of breaking higher-order difference equations.
