A unified procedure for discrete-time root locus and Bode design

As an alternative to the numerous distinct controller design algorithms in discrete-time textbooks, a simple, unified design approach is presented for all standard discrete-time, classical compensators independent of the form of the system information. This approach is based on a simple root locus design procedure for a proportional-derivative (PD) compensator. From this procedure, design procedures for discrete-time lead, proportional-integral (PI), lag, proportional-integral-derivative (PID), and PI-lead compensators are developed. With this proposed approach, students can concentrate on the larger control system design issues, such as compensator selection and closed-loop performance, rather than the intricacies of a particular design procedure. To demonstrate this approach, an example of a lead design from a digital control system laboratory is presented.