Delay-dependent guaranteed cost control for uncertain 2-D discrete systems with state delay in the FM second model

https://doi.org/10.1016/j.jfranklin.2008.08.003Get rights and content

Abstract

This paper is concerned with the problem of delay-dependent guaranteed cost control for uncertain two-dimensional (2-D) state delay systems described by the Fornasini and Marchesini (FM) second state-space model. Given a scalar α(0,1), a sufficient condition for the existence of delay-dependent guaranteed cost controllers is given in terms of a linear matrix inequality (LMI) based on a summation inequality for 2-D discrete systems. A convex optimization problem is proposed to design a state feedback controller stabilizing the 2-D state delay system as well as achieving the least guaranteed cost for the resulting closed-loop system. Finally, the simulation example of thermal processes is given to illustrate the effectiveness of the proposed result.

Introduction

Over the past several decades, two-dimensional (2-D) systems have received considerable attention due to their extensive applications of both theoretical and practical interest [1], [2], [3]. The key feature of a 2-D system is that the information is propagated along two independent directions. Many physical processes, such as image processing [4], signal filtering [5], and thermal processes in chemical reactors, head exchangers and pipe furnaces [3], have a clear 2-D structure. The 2-D system theory is frequently used as an analysis tool to solve some problems, e.g., iterative learning control [6], [7] and repetitive process control [8], [9]. However, the analysis and synthesis approaches for 2-D systems cannot simply extend from existing standard (1-D) system techniques because there are many 2-D system phenomena which have no 1-D system counterparts. Thus the study of 2-D systems is an interesting and challenging topic, and a lot of results have published in the literature. Among these results, Hinamoto [10] established a sufficient condition for the asymptotic stability of 2-D systems described by the Fornasini and Marchesini (FM) second model, Du and Xie [11] present a linear matrix inequality (LMI) approach to solve the robust stability problem for uncertain 2-D systems, Guan et al. [12] and Dhawan et al. [13], [14] dealt with the guaranteed cost control for 2-D systems, Paszke et al. [15] address the guaranteed cost control for discrete linear repetitive processes that are a distinct class of 2-D systems.

Delay systems represent a class of infinite dimensional systems largely used to describe propagation and transport phenomena [16]. In some physical processes which are intrinsically 2-D characteristic, delays appear in a natural way since information transmission along time and/or space require the process of spreading, the presence of delays in a system can also simplify the corresponding process model. Therefore, the control problem for 2-D state delay systems has received some attention. Paszke et al. [17] presented a sufficient stability condition and a stabilization method for discrete linear state delay 2-D systems. In order to guaranteed an adequate level of performance when designing a control system, Chang and Peng [18] first introduced the guaranteed cost control approach. Results on the guaranteed cost control for time-delay systems can be divided into two categories, i.e., delay-independent methods [19], [20] and delay-dependent methods [21], [22], [23]. In the latter methods, the designed controller and the achieved guaranteed costs depend on the size of the time-delay. The delay-dependent guaranteed cost control methods can usually give less guaranteed cost than the delay-independent ones especially when the size of the time-delay is small. In order to reduce the conservatism of delay-dependent conditions, an integral inequality was introduced and controller synthesis conditions [24].

In this paper, we first propose a delay-dependent approach to investigate the guaranteed cost control problem for uncertain 2-D discrete state delay systems described by the FM second model. A Lyapunov–Krasovskii functional is introduced for the 2-D state delay discrete systems. Based on a summation inequality for 2-D discrete state delay systems, a sufficient condition for the existence of delay-dependent guaranteed cost controllers is given in terms of an LMI. A delay-dependent optimal state feedback guaranteed cost controller is obtained by solving an LMI optimization problem. Finally, the simulation example of thermal processes is given to illustrate the effectiveness of the proposed result.

Section snippets

Problem statement and preliminaries

Consider an uncertain 2-D discrete linear system with state delay described by the following FM second state-space modelx(i+1,j+1)=A1x(i,j+1)+A2x(i+1,j)+A1dx(i-d1,j+1)+A2dx(i+1,j-d2)+B1u(i,j+1)+B2u(i+1,j),where 0i,jZ are horizontal and vertical coordinates, x(i,j)Rn is the state vector, u(i,j)Rm is the input vector, d1 and d2 are unknown positive integers representing delays along horizontal direction and vertical direction, respectively; A1,A2,A1d, A2d, B1 and B2 are time-varying matrices,

Main results

In this section, we first present a sufficient condition for the existence of a guaranteed cost controller (7) for the 2-D system (1) with any state delays d1 and d2 satisfying 0<d1d1* and 0<d2d2*.

Theorem 1

Consider the 2-D system (1) with the initial condition (5). For given integers d1*>0 and d2*>0, if there exist a positive scale α<1, matrices M11,M12,M21,M22Rn×n, KRm×n, symmetric positive definite matrices P,S1,S2Rn×n such thatH10Ω11TΩ12T0Ω14T*H2Ω21T0Ω23TΩ24T**-P-1000***-W1-100***0-W2-10*****-(d

An illustrative example

This section applies the main results on guaranteed cost control to the thermal processes in chemical reactors, heat exchangers and pipe furnaces, which can be expressed in the partial differential equation with time delays:T(x,t)x=-T(x,t)t-a0(1+δ)T(x,t)-a1(1+δ)T(x,t-τ)+b(1+δ)u(x,t),where T(x,t) is usually the temperature at x (space) [0,xf] and t (time) [0,], u(x,t) is a given force function, τ is the time delay, a0,a1,b are real coefficients, and δ (|δ|0.2) represents the uncertainty.

Conclusion

This paper has presented a solution to the problem of delay-dependent guaranteed cost control with memoryless state feedback controller for uncertain 2-D state delay systems. In order to reduce the conservatism of delay-dependent conditions, we did not limit the form of the free terms (e.g. M11 and M21) for the summation inequality in deriving delay-dependent results. A controller synthesis condition is obtained in terms of an LMI via the change of variables. A delay-dependent optimal state

References (24)

  • E. Fornasini et al.

    Doubly indexed dynamical, state-space models and structural properties

    Math. System Theory

    (1978)
  • T. Kaczorek
    (1985)
  • Cited by (33)

    • A novel constructive procedure to low-order Fornasini–Marchesini model realization

      2020, Journal of the Franklin Institute
      Citation Excerpt :

      The Fornasini–Marchesini (F–M) (second) models of multidimensional (n-D) systems have received great attention [1–6] since they have been extensively and successfully applied in various fields, such as river pollution [7], real-time implementation of distributed grid sensor networks [8–10], circuit networks [11,12].

    • An improved approach to reliable H <inf>∞</inf> guaranteed cost control for discrete time LPV systems with control input constraints

      2012, Journal of the Franklin Institute
      Citation Excerpt :

      The problem of guaranteed cost control (GCC) for uncertain systems has drawn considerable attention in [1–7].

    • On delay-independent stabilization analysis for a class of switched time-delay systems with the state-driven switching strategy

      2011, Journal of the Franklin Institute
      Citation Excerpt :

      While, considering the concept of the state-driven switching strategy, there exist many choices of switching strategy to make the whole system stable for all individual subsystems are unstable. Furthermore, the time-delay phenomenon also cannot be avoided in practical systems, for instance, chemical process, long distance transmission line, hybrid procedure, electron network, etc. [25–29]. The problem of time-delay may cause instability and poor performance of practical systems.

    • Robust stabilization of polytopic discrete-time systems with time-varying state delay: A convex approach

      2011, Journal of the Franklin Institute
      Citation Excerpt :

      In [15] LMI conditions for robust stability analysis of discrete-time delayed systems with saturation are proposed. In [37] bi-dimensional (2D) discrete-time systems with delayed states are investigated, and delay-independent conditions for norm-bounded uncertainties and constant delay are given by means of nonconvex formulations. In [26] convex conditions have been proposed for discrete-time singular systems with time-invariant delay.

    • On delay-dependent stabilization analysis for the switched time-delay systems with the state-driven switching strategy

      2011, Journal of the Franklin Institute
      Citation Excerpt :

      The switching rules can be obtained using the obtained common positive definite matrix. Furthermore, the time-delay phenomenon is also unavoidable in practical systems [18,19,23–27,29], for instance, chemical process, long distance transmission line, hybrid procedure, electron network, etc. Time-delays may cause instability and poor performance for practical systems.

    View all citing articles on Scopus

    Supported by the National Natural Science Foundation of China under Grant 60525304.

    View full text