Sensitivity and Robustness of Sampled-data Control Systems: A
frequency Domain Viewpoint
Julio H. Braslavsky, Rick H. Middleton and Jim S.
Freudenberg
Abstract
In this paper we consider a frequency domain, input-output based
approach to the analysis of hybrid sampled-data systems. Based on
previous works, we expound a frequency-domain lifting
technique as an alternative to the time-domain
lifting framework for sampled-data systems. In some cases, the
approach pursued here can provide simpler, more intuitive methods
than time-domain lifting techniques to the analysis of the same
problems. As applications, we consider the induced L2 norms
of the hybrid Sensitivity and Complementary Sensitivity Operators,
and the stability robustness of the hybrid system to linear
time-invariant perturbations. In particular, for the SISO case,
``closed form'' expressions arise for the induced norms, and the
conditions for robust stability with multiplicative uncertainty
reduce to a rank-one structured singular value test.
Keywords: Sampled-data systems, Frequency response,
Sensitivity, Robust stability.
25 pages
35 references
112 Kb
