Observability of linear discrete-time systems with different fractional orders
Abstract
In the paper the observability problem for the linear discrete-time positive systems with different fractional orders is presented. Necessary and sufficient conditions for observability of this class of dynamical systems are given. A method for computing the initial state is proposed. Considerations are illustrated by theoretical example. Numerical calculations have been performed in the MATLAB program environment.
Keywords
discrete-time, fractional order, observability, positive, system
Obserwowalność liniowych układów dyskretnych różnych niecałkowitych rzędów
Streszczenie
W pracy rozpatrzono problem obserwowalności układów dyskretnych dodatnich przy różnych niecałkowitych rzędach w równaniu stanu. Podano warunki konieczne i wystarczające obserwowalności rozpatrywanej klasy układów dynamicznych. Zaproponowano prostą metodę wyznaczania nieujemnego stanu początkowego takiego układu. Rozważania zilustrowano przykładem teoretycznym, zaś niezbędne obliczenia wykonano w środowisku programowym MATLAB.
Słowa kluczowe
dodatni, obserwowalność, rząd niecałkowity, układ dyskretny
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