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1.
In this paper, an analytic solution of nonlinear H robust controller is first proposed and used in a complete six degree-of-freedom nonlinear equations of motion of flight vehicle system with mass and moment inertia uncertainties. A special Lyapunov function with mass and moment inertia uncertainties is considered to solve the associated Hamilton-Jacobi partial differential inequality (HJPDI). The HJPDI is solved analytically, resulting in a nonlinear H robust controller with simple proportional feedback structure. Next, the control surface inverse algorithm (CSIA) is introduced to determine the angles of control surface deflection from the nonlinear H control command. The ranges of prefilter and loss ratio that guarantee stability and robustness of nonlinear H flight control system implemented by CSIA are derived. Real aerodynamic data, engine data and actuator system of F-16 aircraft are carried out in numerical simulations to verify the proposed scheme. The results show that the responses still keep good convergence for large initial perturbation and the robust stability with mass and moment inertia uncertainties in the permissible ranges of the prefilter and loss ratio for which this design guarantees stability give same conclusion.  相似文献   

2.
This paper investigates the H guaranteed cost control problem for mode-dependent time-delay jump systems with norm-bounded uncertain parameters. Both distributed delays and input delays appear in the system model. Based on a matrix inequality, a sufficient condition for the existence of robust H guaranteed cost controller is derived, which stabilizes the considered system and guarantees that both the H performance level and a cost function have upper bounds for all admissible uncertainties. By the cone complementary linearization approach, the desired state-feedback controller can be constructed. A numerical example is provided to show the effectiveness of the proposed theoretical results.  相似文献   

3.
This paper is concerned with the H control problem for a class of networked control systems (NCSs) with time-varying delay that is less than one sampling period. By applying a new working mode of the actuator and considering state feedback controllers, a new discrete-time switched system model is proposed to describe the NCS. Based on the obtained switched system model, a sufficient condition is derived for the closed-loop NCS to be exponentially stable and ensure a prescribed H performance level. The obtained condition establishes relations among the delay length, the delay variation frequency, and the system performances of the closed-loop NCS. Moreover, a convex optimization problem is formulated to design the H controllers which minimize the H performance level. An illustrative example is given to show the effectiveness of the proposed results.  相似文献   

4.
This paper addresses the problem of robust H control for uncertain continuous time singular systems with state delays. A new singular-type complete quadratic Lyapunov-Krasovskii functional (LKF) is introduced, which combines with the discretization LKF method to synthesis problems. An improved bounded real lemma (BRL) is presented to ensure the system to be regular, impulse free and stable with H performance condition. Based on the BRL, a memoryless state feedback controller is designed via linear matrix inequalities (LMIs), which greatly reduces the disturbance attenuation level. Numerical examples are given to illustrate improvements over some existing results.  相似文献   

5.
The H control problem is investigated in this paper for a class of networked control systems (NCS) with time-varying delay and packet disordering. A new model is proposed to describe the packet disordering phenomenon and then converted into a parameter-uncertain system with multi-step delay. Based on the obtained system model, a sufficient condition for robust stability of the NCS is derived. Furthermore, an optimization problem with linear matrix inequalities (LMIs) constraints is formulated to design the state feedback H controller such that the closed-loop NCS is robust stable and has an optimal H disturbance attenuation level. Finally, two illustrative examples are given to demonstrate the effectiveness of the proposed method.  相似文献   

6.
This paper investigates the robust HH dynamic output feedback control problem for networked control systems (NCSs) with quantized measurements. The measurement losses of the communicated information are considered in an unreliable communication channel. The robust HH dynamic output feedback controllers are designed to handle the measurement losses and mitigate the quantization effects such that the resultant closed-loop NCS is mean-square stochastically stable with a prescribed HH disturbance attenuation performance. The controller existence conditions can be derived in terms of linear matrix inequalities (LMIs). Finally, an example is provided to illustrate the effectiveness of the proposed approach.  相似文献   

7.
This paper is concerned with the HH output-feedback control problem for a class of discrete-time systems with randomly occurring nonlinearities (RONs) as well as randomly occurring distributed delays (RODDs). Both RONs and RODDs are governed by random variables obeying the Bernoulli distributions. The measurement output is subject to the sensor saturations described by sector-nonlinearities as well as the channel fadings caused typically in wireless communication. The aim of the addressed problem is to design a full-order dynamic output-feedback controller such that, in the simultaneous presence of RONs, RODDs, sensor saturations and channel fadings, the closed-loop system is exponentially mean-square stable and satisfies the prescribed HH performance constraint. By using a combination of the stochastic analysis and Lyapunov functional approaches, sufficient conditions are derived for the existence of the desired controllers and then the characterization of such controllers is given via the semi-definite programme method. Finally, the numerical simulation result is exploited to illustrate the usefulness and effectiveness of the proposed design technique.  相似文献   

8.
Robust fault detection for a class of nonlinear time-delay systems   总被引:1,自引:0,他引:1  
In this paper, the robust fault detection filter (RFDF) design problems are studied for nonlinear time-delay systems with unknown inputs. Firstly, a reference residual model is introduced to formulate the robust fault detection filter design problem as an H model-matching problem. Then appropriate input/output selection matrices are introduced to extend a performance index to the time-delay systems in time domain. The reference residual model designed according to the performance index is an optimal residual generator, which takes into account the robustness against disturbances and sensitivity to faults simultaneously. Applying robust H optimization control technique, the existence conditions of the robust fault detection filter for nonlinear time-delay systems with unknown inputs are presented in terms of linear matrix inequality (LMI) formulation, independently of time delay. An illustrative design example is used to demonstrate the validity and applicability of the proposed approach.  相似文献   

9.
This paper deals with the problems of non-fragile robust stochastic stabilization and robust H control for uncertain stochastic nonlinear time-delay systems. The parameter uncertainties are assumed to be time-varying norm-bounded appearing in both state and input matrices. The time-delay is unknown and time-varying with known bounds. The non-fragile robust stochastic stabilization problem is to design a memoryless non-fragile state feedback controller such that the closed-loop system is robustly stochastically stable for all admissible parameter uncertainties. The purpose of robust H control problem, in addition to robust stochastical stability requirement, is to reduce the effect of the disturbance input on the controlled output to a prescribed level. Using the Lyapunov functional method and free-weighting matrices, delay-dependent sufficient conditions for the solvability of these problems are established in terms of linear matrix inequality (LMI). Numerical example is provided to show the effectiveness of the proposed theoretical results.  相似文献   

10.
This paper deals with the problems of robust delay-dependent stability and H analysis for Markovian jump linear systems with norm-bounded parameter uncertainties and time-varying delays. In terms of linear matrix inequalities, an improved delay-range-dependent stability condition for Markovian jump systems is proposed by constructing a novel Lyapunov-Krasovskii functional with the idea of partitioning the time delay, and a sufficient condition is derived from the H performance. Numerical examples are provided to demonstrate efficiency and reduced conservatism of the results in this paper.  相似文献   

11.
In this paper, the problem of robust H filtering for uncertain systems with time-varying distributed delays is considered. The uncertainties under discussion are time varying but norm bounded. Based on the Lyapunov stability theory, sufficient condition for the existence of full order H filters is proposed by linear matrix inequality (LMI) approach such that the filtering error system is asymptotically sable and satisfies a prescribed attenuation level of noise. A numerical example is given to demonstrate the availability of the proposed method.  相似文献   

12.
This paper presents the central finite-dimensional H filter for nonlinear polynomial systems with multiplicative noise, that is suboptimal for a given threshold γ with respect to a modified Bolza-Meyer quadratic criterion including the attenuation control term with the opposite sign. In contrast to the previously obtained results, the paper reduces the original H filtering problem to the corresponding optimal H2 filtering problem, using the technique proposed in [1]. The paper presents the central suboptimal H filter for the general case of nonlinear polynomial systems with multiplicative noise, based on the optimal H2 filter given in [31]. The central suboptimal H filter is also derived in a closed finite-dimensional form for third (and less) degree polynomial system states. Numerical simulations are conducted to verify performance of the designed central suboptimal filter for nonlinear polynomial systems against the central suboptimal H filters available for polynomial systems with state-independent noise and the corresponding linearized system.  相似文献   

13.
This paper is concerned with finite-time HH control problem for a class of switched linear systems by using a mode-dependent average dwell time (MDADT) method. The switching signal used in this paper is more general than the average dwell time (ADT), in which each mode has its own ADT. By combining the MDADT and Multiple Lyapunov Functions (MLFs) technologies, some sufficient conditions, which can guarantee that the corresponding closed-loop system is finite-time bounded with a prescribed HH performance, are derived for the switched systems. Moreover, a set of mode-dependent dynamic state feedback controllers are designed. Finally, two examples are given to verify the validity of the proposed approaches.  相似文献   

14.
The parametric H loop shaping technique explores more design flexibility by introducing a free parameter that ensures robust stabilization with regard to normalized coprime factor uncertainty of the shaped plant. This paper addresses a design framework for parametric H loop shaping control using linear matrix inequality (LMI) approach that provides a new set of solvability condition along with the larger feasibility region of solution space over the work of Gu et al. (1999) [6]. An equivalence between the Riccati equation based state-space approach and the proposed LMI framework is established and subsequently, an observer-based structure for parametric H loop shaping controller has been realized. A numerical example is considered to demonstrate the effectiveness of the proposed method and the results therein are compared with the work of Gu et al. (1999) [6].  相似文献   

15.
Finite-time stability concerns the boundness of system during a fixed finite-time interval. For switched systems, finite-time stability property can be affected significantly by switching behavior; however, it was neglected by most previous research. In this paper, the problems of finite-time stability analysis and stabilization for switched nonlinear discrete-time systems are addressed. First, sufficient conditions are given to ensure a class of switched nonlinear discrete-time system subjected to norm bounded disturbance finite-time bounded under arbitrary switching, and then the results are extended to H finite-time boundness of switched nonlinear discrete-time systems. Finally based on the results on finite-time boundness, the state feedback controller is designed to H finite-time stabilize a switched nonlinear discrete-time system. A numerical design example is given to illustrate the proposed results within this paper.  相似文献   

16.
This paper studies the problem of robust HH controller design for a class of uncertain Markov jump systems with time-varying transition probabilities, which follows nonhomogeneous jump processes. The time varying transition probability matrix is described as a polytope set. By Lyapunov function approach, under the designed controller, a sufficient condition is presented to ensure that the resulting closed-loop system is stochastically stable and that a prescribed HH performance index is satisfied. Finally, an application of a DC motor device is addressed to demonstrate the effectiveness of developed techniques.  相似文献   

17.
A novel H filter design methodology has been presented for a general class of nonlinear systems. Different from existing nonlinear filtering design, the nonlinearities are approximated using neural networks, and then are modeled based on linear difference inclusions, which makes the structure of the desired filter simpler and parameter turning easier and has the advantages of guaranteed stability, numeral robustness, bounded estimation accuracy. A unified framework is established to solve the addressed H filtering problem by exploiting linear matrix inequality (LMI) approach. A numerical example shows that the filtering error systems will work well against bounded error between a nonlinear dynamical system and a multilayer neural network.  相似文献   

18.
A novel input-to-state approach to the problem of robust state estimation in the presence of model uncertainty as well as plant disturbance and sensor noise is considered. A new observer structure is introduced and shown to have certain advantages over the classical Luenberger observer when studying robustness issues. This structure is then used to solve the robust estimation problem in the H framework.  相似文献   

19.
This paper presents an effective approach to stabilize nonlinear multiple time-delay (NMTD) interconnected systems via a composite of fuzzy controllers and dithers. First, a neural-network (NN) model is employed to approximate each subsystem. Then, the dynamics of the NN model is converted into a linear differential inclusion (LDI) state-space representation. Next, in terms of Lyapunov?s direct method, a delay-dependent stability criterion is derived to guarantee the exponential stability of the NMTD interconnected system. Subsequently, the stability conditions of this criterion are reformulated into a linear matrix inequality (LMI). Based on the LMI, a robustness design of fuzzy control is synthesized not only to stabilize the NMTD interconnected system but also to achieve the optimal H performance by minimizing the disturbance attenuation level. A set of high-frequency signals (commonly referred to as dithers) is simultaneously injected to stabilize the NMTD interconnected system when the designed fuzzy controllers cannot stabilize it. If the dithers’ frequencies are high enough, the outputs of the dithered interconnected system and those of its corresponding mathematical model, the relaxed interconnected system, can be made as close as desired. This makes it possible to get a rigorous prediction of the stability of the dithered interconnected system by establishing the stability of the relaxed interconnected system. Finally, a numerical example with simulations is given to illustrate the feasibility of our approach.  相似文献   

20.
In this paper, a new approach to robust H filtering for a class of nonlinear systems with time-varying uncertainties is proposed in the LMI framework based on a general dynamical observer structure. The nonlinearities under consideration are assumed to satisfy local Lipschitz conditions and appear in both state and measured output equations. The admissible Lipschitz constants of the nonlinear functions are maximized through LMI optimization. The resulting H observer guarantees asymptotic stability of the estimation error dynamics with prespecified disturbance attenuation level and is robust against time-varying parametric uncertainties as well as Lipschitz nonlinear additive uncertainty.  相似文献   

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