Input-Output Stability Analysis of Networked Control Systems
2016 (English)Doctoral thesis, monograph (Other academic)
The main focus of the thesis is to derive stability criteria for networked control system (NCS) models featuring imperfections such as time-varying and constant delays, quantization, packet dropouts, and non-uniform sampling intervals. The main method of proof is based on matrix algebra, as opposed to methods using Lyapunov functions or integral quadratic constraints (IQC). This work puts a particular focus on handling systems with a single integrator. This framework is elaborated in different specific directions as motivated by practical realizations of NCSs, as well as through numerical examples. A novel proof of the discrete time multivariate circle criterion and the Tsypkin criterion for systems including a single integrator is presented, as well as a stability criterion for linear systems with a single integrator subject to variable sampling periods and sector-bounded nonlinear feedback. Four stability criteria for different classes of systems subject to packet loss and time-varying delay are given. Stability criteria for a closed loop system switching between a set of linear time-invariant systems (LTIs) are proved. This result is applied to a single-link NCS with feedback subject to packet loss. Finally, necessary and sufficient conditions for delay-independent stability of an LTI system subject to nonlinear feedback are derived.
Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2016. , 147 p.
Uppsala Dissertations from the Faculty of Science and Technology, ISSN 1104-2516 ; 119
Networked control systems, L2-stability, quantization, delay, packet dropouts, switching systems
Research subject Electrical Engineering with specialization in Automatic Control
IdentifiersURN: urn:nbn:se:uu:diva-272344ISBN: 978-91-554-9452-0OAI: oai:DiVA.org:uu-272344DiVA: diva2:893789
2016-02-26, ITC 2446, Lägerhyddsvägen 2, Uppsala, 09:15 (English)
Glad, Torkel, Prof.
FunderSwedish Foundation for Strategic Research , RIT08-0065