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Metro450 Members Publications

A new view of anti-windup design for uncertain linear systems in the frequency domain

7 August, 2014

Authors: Ari Berger & Per-Olof Gutman

Abstract: This paper presents a somewhat new perspective on the stability problem for uncertain LTI feedback systems with actuator input amplitude saturation. The solution is obtained using the QFT theory and a 3 Dof non-interfering control structure. Describing function analysis is used as a criterion for closed stability and limit cycle avoidance, but the Circle or Popov criteria could also be employed. The novelty is the parameterization of the three degrees of freedom. Two examples are given. The first is a benchmark problem from [1] and a comparison is made with other proposed solutions. The second is an example which was implemented and tested on an X-Y linear stage used for nano-positioning applications. Design and implementation considerations are given.