American Journal of Mathematics and Statistics 2014, 4(5): 222-230
DOI: 10.5923/j.ajms.20140405.03
Robust Asymptotically Stabilization of Special Uncertain
Descriptor Fractional-Order Systems with Fractional
Feedback Control
Sameer Qasim Hasan
*
, Ala Muhsien Abd
Department of Mathematics, Almustansiriyah University, Baghdad, Iraq
Abstract In this paper we investigate the asymptotically stabilization of a special type of singular fractional order α
belongs to interval (0,1) with uncertain parameter as time-invariant and norm-bounded appearing in the state matrix and
suitable feedback fractional control by using Dynamics decomposition form.
Keywords Fractional order, Descriptor system, Fractional, System, Fractional control, Feedback control
1. Introduction
Recently, fractional-order control systems have attracted
increasing interest [15, 9, 11]. On the one hand, this is
mainly due to the fact that many real-world physical systems
are well characterized by fractional-order state equations
[15], i.e., equations involving the so-called fractional
derivatives and integrals. On the other hand, with the success
in the synthesis of real noninteger differentiators and the
emergence of a new electrical circuit element called
“fractance” [10, 21], fractional-order controllers [16, 18, 12]
have been designed and applied to control a variety of
dynamical processes, including integer-order and
fractional-order systems, so as to enhance the robustness and
performance of the control systems. Singular fractional
systems (known as generalized, descriptor of Fractional
systems) describe a large class of systems, which are not
only theoretical interest but also have a great importance in
practice.
Stability is fundamental to all control systems, certainly
including fractional-order control systems [20, 19]. Recently,
stability and stabilization problems of fractional-order linear
time-invariant interval systems have been investigated in [1],
[2, 4]. For example, for fractional-order linear time-invariant
interval systems described in the transfer function form, the
stability issue was discussed first in [13] and then further in
[14]. In this paper we consider the problem of the robust
asymptotical Stabilization for uncertain descriptor
fractional-order systems.
* Corresponding author:
dr.sameer_kasim@yahoo.com (Sameer Qasim Hasan)
Published online at http://journal.sapub.org/ajms
Copyright © 2014 Scientific & Academic Publishing. All Rights Reserved
The descriptor multi-fractional-order systems by applying
a derivative multi-controller and a state feedback.
Controller is given to achieve the robust asymptotical
stabilization of the obtained two sub system, first is
fractional-order systems and the second is zero state.
We using canonical form for the descriptor
fractional-order systems and by applying a derivative
controller and a state feedback controller is given to achieve
the robust asymptotical stabilization of the fractional-order
systems.
In section II, the paper are organized as follow in section II,
we introduce the definition of fractional derivative in brief;
we present also some mathematical results. In section III, we
propose robust linear uncertainty descriptor multi-fractional
controller for the stabilization of system.
2. Preliminaries
A. Some definition
Now we review some important and definition:
The Caputo derivative on the other, defined [17],
α
t
α
α
α-n+1
a
d f(t)
1
dt
D f(t) = dτ
Γ(n - α) (t - τ)
∫
, ( 1 ) n n α − ≤ <
For ( 1 ) n n α − ≤ < and Γ(x) is the well-known
Euler’s gamma function.
Definition (2.1), [22]:
Let [ ]
m n
ij
A aB
×
= ∈ ,
pq
B
×
∈ . Their Kronecker
product (i.e., the direct product or tensor product), denoted
as ( ) A B ⊗ , is defined by