IEEE Transactions on Automatic Control, Vol.62, No.4, 1838-1851, 2017
Intermittent Redesign of Analog Controllers via the Youla Parameter
The paper studies digital redesign of linear time-invariant analog controllers under intermittent sampling. The sampling pattern is only assumed to be uniformly bounded, but otherwise irregular and unknown a priori. The contribution of the paper is twofold. First, it proposes a constructive algorithm to redesign any analog stabilizing controller so that the closed-loop stability is preserved. Second, it is shown that when applied to (sub) optimal H-2 and H-infinity controllers, the algorithm produces (sub) optimal sampled-data solutions under any a priori unknown sampling pattern. The proposed solutions are analytic, computationally simple, implementable, and transparent. Transparency pays off in showing the optimality, under a fixed sampling density, of uniform sampling for both performance measures studied.
Keywords:Controller parametrizations;H-2 and H-infinity optimization;intermittent sampling;sampled-data systems