Computer-aided root -locus numerical technique

Abstract

The existing technique of manual calculation and plotting of root-locus of a control system for stability studies is laborious and time consuming. computer-aided root-locus numerical technique based on simple fast mathematical iteration is developed to eliminate this rigour. Alternative iteration formulas were formed and tested for convergence. A pair of complementary formulas with highest rate of convergence was selected. The process of automatic determination of roots and plotting of root-locus were divided into steps which were analyzed, simplified and coded into computer programs. The geometric properties of the root-loci obtained with this technique are found to conform to those root described in the literature. Root-loci are drawn to scale instead of rough sketches.

Keywords: control system, stability, transient response, root-locus, iteration