A new approach to optimum loop synthesis

Abstract

The need for optimum synthesis procedures for closed loop systems containing plants subject to large parameter variations has long been acknowledged and appropriate design techniques have been developed and refined. However, historically these techniques have been essentially manual in nature and although computer aided design (CAD) implementation of them, where feasible, has eased the designer's burden, it has still been necessary for the designer to provide a considerable amount of interaction with the CAD programs at a routine level. This paper presents a procedure that has been developed specifically for CAD and which synthesizes the loop transfer function directly from plant variation data. In addition, the procedure clarifies two aspects of the synthesis problem which often receive only cursory attention, namely : the choice of the nominal plant and the translation of system time response bounds into the frequency domain.