On the selection of poles in the single-input pole placement problem

It is well known that the single-input pole placement problem can be quite sensitive to perturbations in the data. Recent results by Mehrmann and Xu s how how this sensitivity depends on the location of the poles. In many appl ications it suffices to prescribe a set K in the complex plane that contain s the poles. Mehrmann and Xu formulated a minimization problem for allocati ng the poles in a given set K so that the sensitivity to perturbations is r educed, The present paper uses methods of potential theory to derive simple algorithms that yield approximate solutions of this minimization problem. (C) 1999 Elsevier Science Inc. All rights reserved. AMS classification: 93B 55; 65F15; 65B05.