The problem of realisation of linear control systems with the h−difference of Caputo-, Riemann–Liouville- and Grünwald–Letnikov-type fractional vector-order operators is studied. The problem of existing minimal realisation is discussed.
The problem of realization of a linear input-output map as a positive linear system on a time scale is studied. To state the criteria of existence of realization, modified Markov parameters corresponding to the input-output map are introduced. It is necessary for the existence of a positive realization that the modified Markov parameters be nonnegative. A necessary and sufficient condition for realizability is expressed in the language of positive cones in an infinite dimensional space. The sequence of modified Markov parameters generates one of the cones that appear in the criterion of realizability.
3
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
Linear constant-coefficients control systems with output on arbitrary time scales are studied. Kalman criteria of controllability and observability are extended to such systems. The main problem is to find criteria for an abstract input/output map to have a realization as a system on the time scale. Two different characterizations of realizability are proved. They extend the classical results obtained for continuous-time and discrete-time systems. Minimal realizations and their uniqueness are also studied.
4
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
The question how the classical definition of the Smith zeros of an LTI continuous-time singular control system S(E,A,B,C,D) can be generalized and related to state-space methods is discussed. The zeros are defined as those complex numbers for which there exists a zero direction with a nonzero state-zero direction. Such a definition allows an infinite number of zeros (then the system is called degenerate). A sufficient and necessary condition for nondegeneracy is formulated. Moreover, some characterization of invariant zeros, based on the Weierstrass-Kronecker canonical form of the system and the first nonzero Markov parameter, is obtained.
5
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
In a standard multi-input, multi-output linear time invariant (MIMO LTI) continuous-time system S9A,B,C) the classical notion of the Smith zeros does not characterize fully the output-zeroing problem nor the zero dynamics. The question how this notion can be extended and related to the state-space methods is discussed. Nothing is assumed about the ralationship of the number of inputs to the number of outputs nor about the normal rank of the underlying system matrix. The proposed extension treats multivariable zeros as the triples. Such a treatment is strictly connected with the output zeroing problem and in that spirit the zeros can be easily interpreted even in the degenerate case.
6
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
W niniejszym artykule omówione zostaną metody identyfikacji dynamiki obiektów mechanicznych poprzez identyfikację ich wartości własnych i wektorów własnych, czyli parametrów modalnych. Tym samym zostaną określone parametry, które w pełni opisują dynamikę, przy pominięciu natury fizycznej wybranej konstrukcji, a więc rozkładu w niej: masy, sztywności czy tłumienia. Parametry te są niezbędne nie tylko na potrzeby badań wytężenia konstrukcji, ale również na potrzeby projektowania układów sterowania jego ruchem podstawowym lub drganiami. Omówione metody można stosować zarówno dla obiektów sterowanych jak i niesterowanych.
EN
A short survey of the identification methods of controlled and non-controIled systems is given in the paper. The plant is replacement by its state observer and the observer Markov parameters are calculated. They are used to derive the open-loop system Markov parameters. The Hankel matrices are formed from these parameters to obtain the system realisation.
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.