A controller perturbation technique for transferring closed-loop stability between systems

This brief paper presents a perturbation technique with, which a controller stabilizing one plant may be modified so that it stabilizes a second, related plant. The proposed technique produces an internally stable loop for a broad class of linear systems without requiring any further calculations on the part of the designer. Four seemingly different examples are described in terms of this result. (C) 2003 Elsevier Ltd. All rights reserved.