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State Feedback (state + feedback)

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Engineering100%

Terms modified by State Feedback

  • state feedback control
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  • state feedback controller
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  • state feedback controllers
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    Selected Abstracts

    Reduced pole placement method for cascaded frequency control via dispersed pulse inverters

    EUROPEAN TRANSACTIONS ON ELECTRICAL POWER, Issue 4 2005
    J. Sachau
    Abstract For modular power systems, structures with parallel power inverters are favourable in view of both easy expandability and supply security. The inverters' embedded controllers are implementing voltage and frequency droops and the superimposed frequency control is coupled via fieldbus. This is a case where a superimposed control is acting via one or more locally dispersed subimposed control-loops. As the states of the subimposed loops are inaccessible, their feedback is no longer viable. The method of reduced pole placement allows reformulation of the design task as complete state feedback without employing a feedback of the single virtual state that just globally describes the one or more subimposed systems. Results are presented for a robust grid frequency controller acting via dispersed pulse inverters. Copyright © 2005 John Wiley & Sons, Ltd. [source]

    Nonlinear adaptive tracking-control synthesis for functionally uncertain systems

    INTERNATIONAL JOURNAL OF ADAPTIVE CONTROL AND SIGNAL PROCESSING, Issue 2 2010
    Zenon Zwierzewicz
    Abstract The paper is concerned with the problem of adaptive tracking system control synthesis. It is assumed that a nonlinear, feedback linearizable object dynamics (model structure) is (partially) unknown and some of its nonlinear characteristics can be approximated by a sort of functional approximators. It has been proven that proportional state feedback plus parameter adaptation are able to assure its asymptotic stability. This form of controller permits online compensation of unknown model nonlinearities and exogenous disturbances, which results in satisfactory tracking performance. An interesting feature of the system is that the whole process control is performed without requisite asymptotic convergence of approximator parameters to the postulated ,true' values. It has been noticed that the parameters play rather a role of slack variables on which potential errors (that otherwise would affect the state variables) cumulate. The system's performance has been tested via Matlab/Simulink simulations via an example of ship path-following problem. Copyright © 2009 John Wiley & Sons, Ltd. [source]

    Semi-global stabilization of discrete-time systems subject to non-right invertible constraints

    INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 11 2010
    Xu Wang
    Abstract This paper investigates time-invariant linear systems subject to input and state constraints. We study discrete-time systems with full or partial constraints on both input and state. It has been shown earlier that the solvability conditions of stabilization problems are closely related to important concepts such as the right invertibility or non-right invertibility of the constraints, the location of constraint invariant zeros, and the order of constraint infinite zeros. In this paper, for general time-invariant linear systems with non-right invertible constraints, necessary and sufficient conditions are developed under which semi-global stabilization in the admissible set can be achieved by state feedback. Sufficient conditions are also developed for such a stabilization in the case where measurement feedback is used. Such sufficient conditions are almost necessary. Controllers for both state feedback and measurement feedback are constructed as well. Copyright © 2009 John Wiley & Sons, Ltd. [source]

    H, control for discrete-time Markovian jump linear systems with partly unknown transition probabilities

    INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 8 2009
    Lixian Zhang
    Abstract In this paper, the problem of H, control for a class of discrete-time Markovian jump linear system with partly unknown transition probabilities is investigated. The class of systems under consideration is more general, which covers the systems with completely known and completely unknown transition probabilities as two special cases. Moreover, in contrast to the uncertain transition probabilities studied recently, the concept of partly unknown transition probabilities proposed in this paper does not require any knowledge of the unknown elements. The H, controllers to be designed include state feedback and dynamic output feedback, since the latter covers the static one. The sufficient conditions for the existence of the desired controllers are derived within the matrix inequalities framework, and a cone complementary linearization algorithm is exploited to solve the latent equation constraints in the output-feedback control case. Two numerical examples are provided to show the validness and potential of the developed theoretical results. Copyright © 2008 John Wiley & Sons, Ltd. [source]

    A new finite sum inequality approach to delay-dependent H, control of discrete-time systems with time-varying delay

    INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 6 2008
    Xian-Ming Zhang
    Abstract This paper deals with delay-dependent H, control for discrete-time systems with time-varying delay. A new finite sum inequality is first established to derive a delay-dependent condition, under which the resulting closed-loop system via a state feedback is asymptotically stable with a prescribed H, noise attenuation level. Then, an iterative algorithm involving convex optimization is proposed to obtain a suboptimal H, controller. Finally, two numerical examples are given to show the effectiveness of the proposed method. Copyright © 2007 John Wiley & Sons, Ltd. [source]

    Feedback stabilization of bifurcations in multivariable nonlinear systems,Part II: Hopf bifurcations

    INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 4 2007
    Yong Wang
    Abstract In this paper we derive necessary and sufficient conditions of stabilizability for multi-input nonlinear systems possessing a Hopf bifurcation with the critical mode being linearly uncontrollable, under the non-degeneracy assumption that stability can be determined by the third order term in the normal form of the dynamics on the centre manifold. Stabilizability is defined as the existence of a sufficiently smooth state feedback such that the Hopf bifurcation of the closed-loop system is supercritical, which is equivalent to local asymptotic stability of the system at the bifurcation point. We prove that under the non-degeneracy conditions, stabilizability is equivalent to the existence of solutions to a third order algebraic inequality of the feedback gains. Explicit conditions for the existence of solutions to the algebraic inequality are derived, and the stabilizing feedback laws are constructed. Part of the sufficient conditions are equivalent to the rank conditions of an augmented matrix which is a generalization of the Popov,Belevitch,Hautus (PBH) rank test of controllability for linear time invariant (LTI) systems. We also apply our theory to feedback control of rotating stall in axial compression systems using bleed valve as actuators. Copyright © 2006 John Wiley & Sons, Ltd. [source]

    The Liapunov's second method for continuous time difference equations

    INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 15 2003
    P. PepeArticle first published online: 10 OCT 200
    Abstract Among many other cases such as economic and lossless propagation models, continuous time difference equations are encountered as the internal dynamics in a class of non-linear time delay systems, when controlled by a suitable state feedback which drives the output exponentially to zero. The Liapunov's second method for these infinite dimensional systems has not been extensively investigated in the literature. This paper has the aim of filling this gap. Liapunov's second method theorems for checking the stability and the asymptotic stability of this class of infinite dimensional systems are built up, in both a finite and an infinite dimensional setting. In the finite dimensional setting, the Liapunov function is defined on finite dimensional sets. The conditions for stability are given as inequalities on continuous time. No derivatives are involved, as in the dynamics of the studied systems. In the infinite dimensional setting, the continuous time difference equation is transformed into a discrete time system evolving on an infinite dimensional space, and then the classical Liapunov theorem for the system in the new form is written. In this paper the very general case is considered, that is non-linear continuous time difference equations with multiple non commensurate delays are considered, and moreover the functions involved in the dynamics are allowed to be discontinuous, as well as the initial state. In order to study the stability of the internal dynamics in non-linear time delay feedback systems, an exogenous disturbance is added, which goes to zero exponentially as the time goes to infinity. An example is considered, from non-linear time delay feedback theory. While the results available in the literature are inconclusive as far as the stability of that example is concerned, such stability is proved to hold by the theorems developed in this paper, and is validated by simulation results. Copyright © 2003 John Wiley & Sons, Ltd. [source]

    Some conditions which make the constantly scaled H, control synthesis problems convex

    INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 1 2002
    Toru Asai
    Abstract In this paper, we present some computationally tractable conditions which make the constantly scaled H, control synthesis problem convex. If one of the conditions proposed in this paper holds, the constantly scaled H, control synthesis problem can be solved efficiently as an LMI problem. The results presented here include the existing results such as the state feedback and the full information problems as special cases. In addition, the results are generalized to the case that some of state variables are exactly available. Owing to this generalization, a larger class of problems can be reduced to convex problems, while reduced order controllers can be obtained. Copyright © 2001 John Wiley & Sons, Ltd. [source]

    Robust H, control of stochastic time-delay jumping systems with nonlinear disturbances

    OPTIMAL CONTROL APPLICATIONS AND METHODS, Issue 5 2006
    Guoliang Wei
    Abstract This paper deals with the problems of robust stabilization and H, control for a class of uncertain stochastic jumping systems with nonlinear disturbances and time delays. The uncertain parameters are assumed to be norm-bounded and mode dependent, and the time delays enter into the state matrix, the stochastic perturbation term, as well as the state feedback. The stochastic robust stabilization problem addressed in this paper is to design a state feedback controller with input delay such that, for all admissible uncertainties and the nonlinear disturbances, the closed-loop system is robustly, stochastically, exponentially stable in the mean square. Moreover, the purpose of the robust H, control problem is to guarantee a specified H, performance index, while still achieving the mean-square exponential stability requirement for the closed-loop system. By resorting to the Itô's differential formula and the Lyapunov stability theory, sufficient conditions are derived, respectively, for the robust stabilization and the robust H, control problems. It is shown that the addressed problems can be solved if a set of linear matrix inequalities (LMIs) are feasible. A numerical example is employed to illustrate the usefulness of the proposed LMI-based design methods. Copyright © 2006 John Wiley & Sons, Ltd. [source]

    Optimal disturbance rejection control for singularly perturbed composite systems with time-delay,

    ASIAN JOURNAL OF CONTROL, Issue 3 2009
    Bao-Lin Zhang
    Abstract The optimal control problem for a class of singularly perturbed time-delay composite systems affected by external disturbances is investigated. The system is decomposed into a fast linear subsystem and a slow time-delay subsystem with disturbances. For the slow subsystem, the feedforward compensation technique is proposed to reject the disturbances, and the successive approximation approach (SAA) is applied to decompose it into decoupled subsystems and solve the two-point boundary value (TPBV) problem. By combining with the optimal control law of the fast subsystem, the feedforward and feedback composite control (FFCC) law of the original composite system is obtained. The FFCC law consists of analytic state feedback and feedforward terms and a compensation term which is the limit of the adjoint vector sequence. The compensation term can be obtained from an iteration formula of adjoint vectors. Simulation results are employed to test the validity of the proposed design algorithm. Copyright © 2009 John Wiley and Sons Asia Pte Ltd and Chinese Automatic Control Society [source]

    NON-BLOCKING SUPERVISORY CONTROL FOR INITIALISED RECTANGULAR AUTOMATA

    ASIAN JOURNAL OF CONTROL, Issue 2 2004
    Michael P. Spathopoulos
    ABSTRACT We consider the problem of supervisory control for a class of rectangular automata and more specifically for compact rectangular automata with uniform rectangular activity, i.e. initialised. The supervisory controller is state feedback and disables discrete-event transitions in order to solve the non-blocking forbidden state problem. The non-blocking problem is defined under both strong and weak conditions. For the latter maximally permissive solutions that are computable on a finite quotient space characterised by language equivalence are derived. [source]