Extension of continuous-data system design techniques to sampled-data control systems

THE purpose of this paper is to extend the utility of certain synthesis techniques, which have proved useful in the design of continuous feedback systems, to the study of sampled-data systems. In recent publications,1,3,6 the z-transformation has been utilized to advantage in simplifying the analysis of sampled-data systems. However, several useful techniques applicable to the design of continuous-data systems have not been made available for the design of sampled-data systems. In this paper, by means of an extension of the concepts embodied in the z-transformation, the application to sampled-data systems of root-locus plots, asymptotic frequency plots, and Routh's criterion is shown to be feasible. Through the use of these techniques, a digital program giving the desired system compensation is readily synthesized.