An advanced fuzzy C-mean （FCM） algorithm was proposed for the efficient regional clustering of multi-nodes interconnected systems. Due to various locational prices and regional coherencies for each node and point, m...An advanced fuzzy C-mean （FCM） algorithm was proposed for the efficient regional clustering of multi-nodes interconnected systems. Due to various locational prices and regional coherencies for each node and point, modified similarity measure was considered to gather nodes having similar characteristics. The similarity measure was needed to contain locafi0nal prices as well as regional coherency. In order to consider the two properties simultaneously, distance measure of fuzzy C-mean algorithm had to be modified. Regional clustering algorithm for interconnected power systems was designed based on the modified fuzzy C-mean algorithm. The proposed algorithm produces proper classification for the interconnected power system and the results are demonstrated in the example of IEEE 39-bus interconnected electricity system.展开更多
This paper considers a fault-tolerant control and vibration suppression problem of flexible spacecraft.The attitude dynamics is modeled by an interconnected system,in which the rigid part and the flexible part are cou...This paper considers a fault-tolerant control and vibration suppression problem of flexible spacecraft.The attitude dynamics is modeled by an interconnected system,in which the rigid part and the flexible part are coupled with each other.Such a model allows us to use the interconnected system approach to analyze the flexible spacecraft.Both distributed and decentralized observer-based fault-tolerant control schemes are developed,under which the closed-loop stability of flexible spacecraft can be ensured by using the cycle-small-gain theorem.Compared with the traditional method,this paper considers the faults occurred not only in the rigid parts,but also in the flexible parts.In addition,the application of the interconnected system approach simplifies the system model of flexible spacecraft,thereby the difficulty of theoretical analysis and engineering practice of fault-tolerant control of flexible spacecraft are greatly reduced.Simulation results show the effectiveness of the proposed methods and the comparison of different fault-tolerant control approach.展开更多
This paper deals with analysis and synthesis problems of spatially interconnected systems where communicated information may get lost between subsystems. Spatial shift operator and temporal forward shift operator are ...This paper deals with analysis and synthesis problems of spatially interconnected systems where communicated information may get lost between subsystems. Spatial shift operator and temporal forward shift operator are introduced to model the interconnected systems as discrete time-space multidimensional linear systems with Markovian jumping parameters which reflect the state of communication channels. To ensure the whole system＇s well-posedness and mean square stability for a given packet loss rate, a condition is derived through analysis. Then a procedure of designing distributed dynamic output feedback controllers is proposed. The controllers have the same structure as the plants and are solved within the linear matrix inequality （LMI） framework. Finally, we apply these results to study the effect of communication losses on the multiple vehicle platoon control system, which further illustrates the effectiveness of the proposed model and method.展开更多
This article considers delay dependent decentralized H∞ filtering for a class of uncertain interconnected systems, where the uncertainties are assumed to be time varying and satisfy the norm-bounded conditions. First...This article considers delay dependent decentralized H∞ filtering for a class of uncertain interconnected systems, where the uncertainties are assumed to be time varying and satisfy the norm-bounded conditions. First, combining the Lyapunov-Krasovskii functional approach and the delay integral inequality of matrices, a sufficient condition of the existence of the robust decentralized H∞ filter is derived, which makes the error systems asymptotically stable and satisfies the H∞ norm of the transfer function from noise input to error output less than the specified up-bound on the basis of the form of uncertainties. Then, the above sufficient condition is transformed to a system of easily solvable LMIs via a series of equivalent transformation. Finally, the numerical simulation shows the efficiency of the main results.展开更多
This paper is concerned with the decentralized stabilization of continuous and discrete linear interconnected systems with the structural constraints about the interconnection matrices. For the continuous case,the mai...This paper is concerned with the decentralized stabilization of continuous and discrete linear interconnected systems with the structural constraints about the interconnection matrices. For the continuous case,the main improvement in the paper as compared with the corresponding results in the literature is to extend the considered class of systems from S to S (both will be defined in the paper) without resulting in high decentralized gain and difficult numerical computation. The algorithm for obtaining decentralized state feedback control to stable the overall system is presented. The discrete case and some very useful results are discussed as well.展开更多
This paper studies the problem of robust H∞ control design for a class of uncertain interconnected systems via state feedback. This class of systems are described by a state space model, which contains unknown nonlin...This paper studies the problem of robust H∞ control design for a class of uncertain interconnected systems via state feedback. This class of systems are described by a state space model, which contains unknown nonlinear interaction and time-varying norm-bounded parametric uncertainties in state equation. Using the Riccati-equation-based approach we design state feedback control laws, which guarantee the decentralized stability with disturbance attenuation for the interconnected uncertain systems. A simple example of an interconnected uncertain linear system is presented to illustrate the results.展开更多
In this paper,a novel finite-time distributed identification method is introduced for nonlinear interconnected systems.A distributed concurrent learning-based discontinuous gradient descent update law is presented to ...In this paper,a novel finite-time distributed identification method is introduced for nonlinear interconnected systems.A distributed concurrent learning-based discontinuous gradient descent update law is presented to learn uncertain interconnected subsystems’dynamics.The concurrent learning approach continually minimizes the identification error for a batch of previously recorded data collected from each subsystem as well as its neighboring subsystems.The state information of neighboring interconnected subsystems is acquired through direct communication.The overall update laws for all subsystems form coupled continuous-time gradient flow dynamics for which finite-time Lyapunov stability analysis is performed.As a byproduct of this Lyapunov analysis,easy-to-check rank conditions on data stored in the distributed memories of subsystems are obtained,under which finite-time stability of the distributed identifier is guaranteed.These rank conditions replace the restrictive persistence of excitation(PE)conditions which are hard and even impossible to achieve and verify for interconnected subsystems.Finally,simulation results verify the effectiveness of the presented distributed method in comparison with the other methods.展开更多
This paper focuses on the problem of non-fragile decentralized guaranteed cost control for uncertain neutral large-scale interconnected systems with time-varying delays in state,control input and interconnections.A no...This paper focuses on the problem of non-fragile decentralized guaranteed cost control for uncertain neutral large-scale interconnected systems with time-varying delays in state,control input and interconnections.A novel scheme,viewing the interconnections with time-varying delays as effective information but not disturbances,is developed.Based on Lyapunov stability theory,using various techniques of decomposing and magnifying matrices,a design method of the non-fragile decentralized guaranteed cost controller for unperturbed neutral large-scale interconnected systems is proposed and the guaranteed cost is presented.The further results are derived for the uncertain case from the criterion of unperturbed neutral large-scale interconnected systems.Finally,an illustrative example shows that the results are significantly better than the existing results in the literatures.展开更多
The paper addresses the decentralized optimal control and stabilization problems for interconnected systems subject to asymmetric information.Compared with previous work,a closed-loop optimal solution to the control p...The paper addresses the decentralized optimal control and stabilization problems for interconnected systems subject to asymmetric information.Compared with previous work,a closed-loop optimal solution to the control problem and sufficient and necessary conditions for the stabilization problem of the interconnected systems are given for the first time.The main challenge lies in three aspects:Firstly,the asymmetric information results in coupling between control and estimation and failure of the separation principle.Secondly,two extra unknown variables are generated by asymmetric information(different information filtration)when solving forward-backward stochastic difference equations.Thirdly,the existence of additive noise makes the study of mean-square boundedness an obstacle.The adopted technique is proving and assuming the linear form of controllers and establishing the equivalence between the two systems with and without additive noise.A dual-motor parallel drive system is presented to demonstrate the validity of the proposed algorithm.展开更多
The notion of string stability of a countably infinite interconnection of a class of nonlinear system was introduced. Intuitively, string stability implies uniform boundedness of all the stares of the interconnected s...The notion of string stability of a countably infinite interconnection of a class of nonlinear system was introduced. Intuitively, string stability implies uniform boundedness of all the stares of the interconnected system for all time if the initial states of the interconnected system are uniformly bounded. Vector V-function method used to judge the stability is generalized for infinite interconnected system and sufficient conditions which guarantee the asymptotic string stability of a class of interconnected system are given. The stability regions obtained here are much larger than those in previous papers. The method given here overcomes some difficulties to deal with stability of infinite nonlinear interconnected system in previous papers.展开更多
The problem of robust exponential stability for a class of switched nonlineardynamical systems with uncertainties and unbounded delay is addressed. On the assump-tion that the interconnected functions of the studied s...The problem of robust exponential stability for a class of switched nonlineardynamical systems with uncertainties and unbounded delay is addressed. On the assump-tion that the interconnected functions of the studied systems satisfy the Lipschitz condition,by resorting to vector Lyapunov approach and M-matrix theory, the sufficient conditions toensure the robust exponential stability of the switched interconnected systems under arbi-trary switching are obtained. The proposed method, which neither require the individualsubsystems to share a Common Lyapunov Function （CLF）, nor need to involve the values ofindividual Lyapunov functions at each switching time, provide a new way of thinking to studythe stability of arbitrary switching. In addition, the proposed criteria are explicit, and it isconvenient for practical applications. Finally, two numerical examples are given to illustratethe correctness and effectiveness of the proposed theories.展开更多
The robust decentralized adaptive output-feedback stabilization for a class of interconnected systems with static and dynamic interconnections by using the MT-filters and backstepping design method is studied. By intr...The robust decentralized adaptive output-feedback stabilization for a class of interconnected systems with static and dynamic interconnections by using the MT-filters and backstepping design method is studied. By introducing a new filtered transformation, the adaptive laws were derived for measurement. Under the assumption of the nonlinear growth conditions imposed on the nonlinear interconnections and by constructing the error system and using a new proof method, the global stability of the closed-loop system was effectively analyzed, and the exponential convergence of all the signals except for parameter estimates were guaranteed.展开更多
This paper focuses on a class of T-S fuzzy interconnected systems with time delays and time-varying parameter uncertainties. Observer-based output feedback decentralized controller is designed such that the closed-loo...This paper focuses on a class of T-S fuzzy interconnected systems with time delays and time-varying parameter uncertainties. Observer-based output feedback decentralized controller is designed such that the closed-loop interconnected system is asymptotically stable in the Lyapunov sense in probability for all admissible uncertainties and time delays. Sufficient conditions for robustly asymptotically stability of the systems are given in terms of a set of linear matrix inequalities （LMIs）.展开更多
This paper studies the delay-dependent stability problem of discrete-time interconnected systems with time-varying delays.By using vector Lyapunov function approach and linear matrix inequalities （LMIs）,new stabilit...This paper studies the delay-dependent stability problem of discrete-time interconnected systems with time-varying delays.By using vector Lyapunov function approach and linear matrix inequalities （LMIs）,new stability conditions are derived.These results proposed in this paper are all at subsystems level.After comparing with the existing results,it is shown that these conditions are less conservative.A numerical example is presented to demonstrate the effectiveness of the results.展开更多
A great deal of stabilization criteria has been obtained from study of stabilizing interconnected systems. The results obtained are usually based on continuous systems by state feedback. In this paper, decentralized i...A great deal of stabilization criteria has been obtained from study of stabilizing interconnected systems. The results obtained are usually based on continuous systems by state feedback. In this paper, decentralized impulsive control is presented to stabilize a class of uncertain interconnected systems based on Lyapunov theory. The system under consideration involves parameter uncertainties and unknown nonlinear interactions among subsystems. Some new criteria of stabilization under impulsive control are established. Two numerical examples are offered to prove the effectiveness and practicality of the proposed method.展开更多
The decentralized stabilization conditions for large-scale linear interconnection systems with time-varying delays were established by using some different decomposition cases of interconnection matrices, and a method...The decentralized stabilization conditions for large-scale linear interconnection systems with time-varying delays were established by using some different decomposition cases of interconnection matrices, and a method for designing the decentralized local memoryless state feedback controllers was proposed. All of the considered delays are continuous function, and satisfy some conditions.展开更多
This paper deals with the control of arbitrarily topological interconnected systems where information communicated between subsystems may be lost due to unreliable links.First,the stochastic variable that is responsib...This paper deals with the control of arbitrarily topological interconnected systems where information communicated between subsystems may be lost due to unreliable links.First,the stochastic variable that is responsible for the communication status of lossy network is regarded as a source of model uncertainty.The system is modeled in the framework of linear fractional transformation with a deterministic nominal system and a stochastic model uncertainty.Then,the robust control theory is employed for system analysis.The largest probability of communication failure,tolerated by the interconnected systems keeping mean square stable,can be obtained by solving aμsynthesis optimization problem.Decentralized state feedback controllers are designed to ensure that the whole system is mean square stable for a given communication failure rate,based on the technique of linear matrix inequalities.An illustrative example is presented finally to verify the effectiveness of the proposed model and method.展开更多
This paper considers the design of distributed control architecture for spatially interconnected systems that are composed of several similar interconnected sub-units.Each sub-unit is a linear continuous time system a...This paper considers the design of distributed control architecture for spatially interconnected systems that are composed of several similar interconnected sub-units.Each sub-unit is a linear continuous time system and directly interacts with its nearest neighbors.This class of systems exists in several applications such as automated highway systems,power systems,and computer networks.Hybrid Lyapunov criterion and the hybrid real bounded lemma are derived to determine the stability and Hoo performance of the overall system.In order to stabilize this class of systems,distributed dynamic output feedback controllers are considered,and tractable linear matrix inequality(LMI)-based algorithms for the derivation of distributed controllers are presented.The change variable approach is introduced in the LMI-based algorithms due to its higher efficiency and numerically stable implementation than the elimination algorithm as introduced in previous works.It is shown through a numerical example that the distributed Ho~controllers developed in this article are superior to decentralized controllers in several aspects.展开更多
Energy equity refers to the condition in which access to the cleaner energy required by individuals is equally available to all.To relieve the energy expenditures-the key component in the concept of energy equity–of ...Energy equity refers to the condition in which access to the cleaner energy required by individuals is equally available to all.To relieve the energy expenditures-the key component in the concept of energy equity–of low-income communities,governments worldwide have imposed caps on soaring energy prices.However,the inherent mechanisms within the operational schedule remain undiscussed.This paper innovatively provides guidelines for operators to embed energy burden policies into the bulk power system model,by answering two critical questions.①What is the impact on system price pattern when embedding the locational price constraints?②How to reformulate the tie-line schedule to meet the equity thresholds?Consequently,a novel bi-level energy equity-constrained tie-line scheduling model is proposed.The conventional economic dispatch is solved at the upper level,and then a preliminary operational schedule is given to the lower level,where we propose an energy equity slackness component variable to evaluate the gap between preliminary and desired equity-satisfied operational schedules.The implicit constraints on the price are converted into explicit feasibility cuts with dual theory.Case studies on test systems demonstrate the reduced energy expenditure for underserved communities,and the optimal tie-line schedule is also validated.展开更多
The paper considers a class of interconnected nonlinear systems with unknown sensor faults and uncertain interactions.Each subsystem is subject not only to the local sensor faults but also to the possible effects of f...The paper considers a class of interconnected nonlinear systems with unknown sensor faults and uncertain interactions.Each subsystem is subject not only to the local sensor faults but also to the possible effects of faults from other subsystems through uncertain interactions.Both multiplicative and time-varying additive sensor faults are taken into consideration,which are allowed to be unknown.A decentralized adaptive fault-tolerant control(FTC)scheme has been established.To eliminate the effects of faults in the control loop,several auxiliary quantities are constructed wisely and estimated by the designed adaptive mechanism.A smooth function is proposed,by which the uncertain interactions can be compensated even if they are coupled with sensor faults.It is proved that,by using only the corrupted states,all the closed-loop signals are globally uniformly bounded,and the output tracking error converges into an adjustable residual set.Finally,simulation and comparison studies are presented to illustrate the effectiveness of the proposed scheme.展开更多
基金Work supported by the Second Stage of Brain Korea 21 ProjectsWork(2010-0020163) supported by Priority Research Centers Program through the National Research Foundation (NRF) funded by the Ministry of Education,Science and Technology of Korea
文摘An advanced fuzzy C-mean （FCM） algorithm was proposed for the efficient regional clustering of multi-nodes interconnected systems. Due to various locational prices and regional coherencies for each node and point, modified similarity measure was considered to gather nodes having similar characteristics. The similarity measure was needed to contain locafi0nal prices as well as regional coherency. In order to consider the two properties simultaneously, distance measure of fuzzy C-mean algorithm had to be modified. Regional clustering algorithm for interconnected power systems was designed based on the modified fuzzy C-mean algorithm. The proposed algorithm produces proper classification for the interconnected power system and the results are demonstrated in the example of IEEE 39-bus interconnected electricity system.
基金supported by National Natural Science Foundation of China(Nos.61622304,61773201)Natural Science Foundation of Jiangsu Province,China(No.BK20160035)Fundamental Research Funds for the Central Universities,China(No.NE2015002)。
文摘This paper considers a fault-tolerant control and vibration suppression problem of flexible spacecraft.The attitude dynamics is modeled by an interconnected system,in which the rigid part and the flexible part are coupled with each other.Such a model allows us to use the interconnected system approach to analyze the flexible spacecraft.Both distributed and decentralized observer-based fault-tolerant control schemes are developed,under which the closed-loop stability of flexible spacecraft can be ensured by using the cycle-small-gain theorem.Compared with the traditional method,this paper considers the faults occurred not only in the rigid parts,but also in the flexible parts.In addition,the application of the interconnected system approach simplifies the system model of flexible spacecraft,thereby the difficulty of theoretical analysis and engineering practice of fault-tolerant control of flexible spacecraft are greatly reduced.Simulation results show the effectiveness of the proposed methods and the comparison of different fault-tolerant control approach.
文摘This paper deals with analysis and synthesis problems of spatially interconnected systems where communicated information may get lost between subsystems. Spatial shift operator and temporal forward shift operator are introduced to model the interconnected systems as discrete time-space multidimensional linear systems with Markovian jumping parameters which reflect the state of communication channels. To ensure the whole system＇s well-posedness and mean square stability for a given packet loss rate, a condition is derived through analysis. Then a procedure of designing distributed dynamic output feedback controllers is proposed. The controllers have the same structure as the plants and are solved within the linear matrix inequality （LMI） framework. Finally, we apply these results to study the effect of communication losses on the multiple vehicle platoon control system, which further illustrates the effectiveness of the proposed model and method.
基金the National Natural Science Foundation of China (60634020)the Hunan Provincial Natural Science Foundation of China (07JJ6138)+1 种基金the Postdoctoral Science Foundation of China (20060390883)the China Ph.D. Discipline Special Foundation (20050533028).
文摘This article considers delay dependent decentralized H∞ filtering for a class of uncertain interconnected systems, where the uncertainties are assumed to be time varying and satisfy the norm-bounded conditions. First, combining the Lyapunov-Krasovskii functional approach and the delay integral inequality of matrices, a sufficient condition of the existence of the robust decentralized H∞ filter is derived, which makes the error systems asymptotically stable and satisfies the H∞ norm of the transfer function from noise input to error output less than the specified up-bound on the basis of the form of uncertainties. Then, the above sufficient condition is transformed to a system of easily solvable LMIs via a series of equivalent transformation. Finally, the numerical simulation shows the efficiency of the main results.
基金National Natural Science Foundation of China(1 970 1 0 2 2 )
文摘This paper is concerned with the decentralized stabilization of continuous and discrete linear interconnected systems with the structural constraints about the interconnection matrices. For the continuous case,the main improvement in the paper as compared with the corresponding results in the literature is to extend the considered class of systems from S to S (both will be defined in the paper) without resulting in high decentralized gain and difficult numerical computation. The algorithm for obtaining decentralized state feedback control to stable the overall system is presented. The discrete case and some very useful results are discussed as well.
文摘This paper studies the problem of robust H∞ control design for a class of uncertain interconnected systems via state feedback. This class of systems are described by a state space model, which contains unknown nonlinear interaction and time-varying norm-bounded parametric uncertainties in state equation. Using the Riccati-equation-based approach we design state feedback control laws, which guarantee the decentralized stability with disturbance attenuation for the interconnected uncertain systems. A simple example of an interconnected uncertain linear system is presented to illustrate the results.
基金This work was partially supported by the European Union’s Horizon 2020 research and innovation programme(739551)(KIOS CoE)from the Republic of Cyprus through the Directorate General for European Programmes,Coordination and Development.
文摘In this paper,a novel finite-time distributed identification method is introduced for nonlinear interconnected systems.A distributed concurrent learning-based discontinuous gradient descent update law is presented to learn uncertain interconnected subsystems’dynamics.The concurrent learning approach continually minimizes the identification error for a batch of previously recorded data collected from each subsystem as well as its neighboring subsystems.The state information of neighboring interconnected subsystems is acquired through direct communication.The overall update laws for all subsystems form coupled continuous-time gradient flow dynamics for which finite-time Lyapunov stability analysis is performed.As a byproduct of this Lyapunov analysis,easy-to-check rank conditions on data stored in the distributed memories of subsystems are obtained,under which finite-time stability of the distributed identifier is guaranteed.These rank conditions replace the restrictive persistence of excitation(PE)conditions which are hard and even impossible to achieve and verify for interconnected subsystems.Finally,simulation results verify the effectiveness of the presented distributed method in comparison with the other methods.
基金supported by the National Natural Science Foundation of China(6057401160972164+1 种基金60904101)the Scientific Research Fund of Liaoning Provincial Education Department(2009A544)
文摘This paper focuses on the problem of non-fragile decentralized guaranteed cost control for uncertain neutral large-scale interconnected systems with time-varying delays in state,control input and interconnections.A novel scheme,viewing the interconnections with time-varying delays as effective information but not disturbances,is developed.Based on Lyapunov stability theory,using various techniques of decomposing and magnifying matrices,a design method of the non-fragile decentralized guaranteed cost controller for unperturbed neutral large-scale interconnected systems is proposed and the guaranteed cost is presented.The further results are derived for the uncertain case from the criterion of unperturbed neutral large-scale interconnected systems.Finally,an illustrative example shows that the results are significantly better than the existing results in the literatures.
基金supported by the National Natural Science Foundation of China(62273213,62073199,62103241)Natural Science Foundation of Shandong Province for Innovation and Development Joint Funds(ZR2022LZH001)+4 种基金Natural Science Foundation of Shandong Province(ZR2020MF095,ZR2021QF107)Taishan Scholarship Construction Engineeringthe Original Exploratory Program Project of National Natural Science Foundation of China(62250056)Major Basic Research of Natural Science Foundation of Shandong Province(ZR2021ZD14)High-level Talent Team Project of Qingdao West Coast New Area(RCTD-JC-2019-05)。
文摘The paper addresses the decentralized optimal control and stabilization problems for interconnected systems subject to asymmetric information.Compared with previous work,a closed-loop optimal solution to the control problem and sufficient and necessary conditions for the stabilization problem of the interconnected systems are given for the first time.The main challenge lies in three aspects:Firstly,the asymmetric information results in coupling between control and estimation and failure of the separation principle.Secondly,two extra unknown variables are generated by asymmetric information(different information filtration)when solving forward-backward stochastic difference equations.Thirdly,the existence of additive noise makes the study of mean-square boundedness an obstacle.The adopted technique is proving and assuming the linear form of controllers and establishing the equivalence between the two systems with and without additive noise.A dual-motor parallel drive system is presented to demonstrate the validity of the proposed algorithm.
文摘The notion of string stability of a countably infinite interconnection of a class of nonlinear system was introduced. Intuitively, string stability implies uniform boundedness of all the stares of the interconnected system for all time if the initial states of the interconnected system are uniformly bounded. Vector V-function method used to judge the stability is generalized for infinite interconnected system and sufficient conditions which guarantee the asymptotic string stability of a class of interconnected system are given. The stability regions obtained here are much larger than those in previous papers. The method given here overcomes some difficulties to deal with stability of infinite nonlinear interconnected system in previous papers.
基金supported by the Natural Science Foundation of China(11572264)the Foundation for Distinguished Young Talents in Higher Education of Guangdong(2016KQNCX103)
文摘The problem of robust exponential stability for a class of switched nonlineardynamical systems with uncertainties and unbounded delay is addressed. On the assump-tion that the interconnected functions of the studied systems satisfy the Lipschitz condition,by resorting to vector Lyapunov approach and M-matrix theory, the sufficient conditions toensure the robust exponential stability of the switched interconnected systems under arbi-trary switching are obtained. The proposed method, which neither require the individualsubsystems to share a Common Lyapunov Function （CLF）, nor need to involve the values ofindividual Lyapunov functions at each switching time, provide a new way of thinking to studythe stability of arbitrary switching. In addition, the proposed criteria are explicit, and it isconvenient for practical applications. Finally, two numerical examples are given to illustratethe correctness and effectiveness of the proposed theories.
基金This work was supported by the National Natural Science Foundation of China (No. 60304003), the Natural Science Foundation of Shandong Province (Q2002G02), and the Doctoral Foundation of Shandong Province (No. 03BS092).
文摘The robust decentralized adaptive output-feedback stabilization for a class of interconnected systems with static and dynamic interconnections by using the MT-filters and backstepping design method is studied. By introducing a new filtered transformation, the adaptive laws were derived for measurement. Under the assumption of the nonlinear growth conditions imposed on the nonlinear interconnections and by constructing the error system and using a new proof method, the global stability of the closed-loop system was effectively analyzed, and the exponential convergence of all the signals except for parameter estimates were guaranteed.
基金This work was supported by the National Nature Science Foundation of China (No. 60474038, No.70431002)the NSF for Distinguished Young Scholars of P. R.China (No. 60225013)
文摘This paper focuses on a class of T-S fuzzy interconnected systems with time delays and time-varying parameter uncertainties. Observer-based output feedback decentralized controller is designed such that the closed-loop interconnected system is asymptotically stable in the Lyapunov sense in probability for all admissible uncertainties and time delays. Sufficient conditions for robustly asymptotically stability of the systems are given in terms of a set of linear matrix inequalities （LMIs）.
基金supported by the Postdoctoral Science Foundation of China(No.20090451275)the Scientific Research Program for the Education Department of Liaoning Province of China(No.2008017)the National Nature Science foundation of China(No.61074040)
文摘This paper studies the delay-dependent stability problem of discrete-time interconnected systems with time-varying delays.By using vector Lyapunov function approach and linear matrix inequalities （LMIs）,new stability conditions are derived.These results proposed in this paper are all at subsystems level.After comparing with the existing results,it is shown that these conditions are less conservative.A numerical example is presented to demonstrate the effectiveness of the results.
文摘A great deal of stabilization criteria has been obtained from study of stabilizing interconnected systems. The results obtained are usually based on continuous systems by state feedback. In this paper, decentralized impulsive control is presented to stabilize a class of uncertain interconnected systems based on Lyapunov theory. The system under consideration involves parameter uncertainties and unknown nonlinear interactions among subsystems. Some new criteria of stabilization under impulsive control are established. Two numerical examples are offered to prove the effectiveness and practicality of the proposed method.
文摘The decentralized stabilization conditions for large-scale linear interconnection systems with time-varying delays were established by using some different decomposition cases of interconnection matrices, and a method for designing the decentralized local memoryless state feedback controllers was proposed. All of the considered delays are continuous function, and satisfy some conditions.
文摘This paper deals with the control of arbitrarily topological interconnected systems where information communicated between subsystems may be lost due to unreliable links.First,the stochastic variable that is responsible for the communication status of lossy network is regarded as a source of model uncertainty.The system is modeled in the framework of linear fractional transformation with a deterministic nominal system and a stochastic model uncertainty.Then,the robust control theory is employed for system analysis.The largest probability of communication failure,tolerated by the interconnected systems keeping mean square stable,can be obtained by solving aμsynthesis optimization problem.Decentralized state feedback controllers are designed to ensure that the whole system is mean square stable for a given communication failure rate,based on the technique of linear matrix inequalities.An illustrative example is presented finally to verify the effectiveness of the proposed model and method.
基金Supported by the Funds for Creative Graduate Groups of Beijing Institute of Technology(GA200803)
文摘This paper considers the design of distributed control architecture for spatially interconnected systems that are composed of several similar interconnected sub-units.Each sub-unit is a linear continuous time system and directly interacts with its nearest neighbors.This class of systems exists in several applications such as automated highway systems,power systems,and computer networks.Hybrid Lyapunov criterion and the hybrid real bounded lemma are derived to determine the stability and Hoo performance of the overall system.In order to stabilize this class of systems,distributed dynamic output feedback controllers are considered,and tractable linear matrix inequality(LMI)-based algorithms for the derivation of distributed controllers are presented.The change variable approach is introduced in the LMI-based algorithms due to its higher efficiency and numerically stable implementation than the elimination algorithm as introduced in previous works.It is shown through a numerical example that the distributed Ho~controllers developed in this article are superior to decentralized controllers in several aspects.
文摘Energy equity refers to the condition in which access to the cleaner energy required by individuals is equally available to all.To relieve the energy expenditures-the key component in the concept of energy equity–of low-income communities,governments worldwide have imposed caps on soaring energy prices.However,the inherent mechanisms within the operational schedule remain undiscussed.This paper innovatively provides guidelines for operators to embed energy burden policies into the bulk power system model,by answering two critical questions.①What is the impact on system price pattern when embedding the locational price constraints?②How to reformulate the tie-line schedule to meet the equity thresholds?Consequently,a novel bi-level energy equity-constrained tie-line scheduling model is proposed.The conventional economic dispatch is solved at the upper level,and then a preliminary operational schedule is given to the lower level,where we propose an energy equity slackness component variable to evaluate the gap between preliminary and desired equity-satisfied operational schedules.The implicit constraints on the price are converted into explicit feasibility cuts with dual theory.Case studies on test systems demonstrate the reduced energy expenditure for underserved communities,and the optimal tie-line schedule is also validated.
文摘The paper considers a class of interconnected nonlinear systems with unknown sensor faults and uncertain interactions.Each subsystem is subject not only to the local sensor faults but also to the possible effects of faults from other subsystems through uncertain interactions.Both multiplicative and time-varying additive sensor faults are taken into consideration,which are allowed to be unknown.A decentralized adaptive fault-tolerant control(FTC)scheme has been established.To eliminate the effects of faults in the control loop,several auxiliary quantities are constructed wisely and estimated by the designed adaptive mechanism.A smooth function is proposed,by which the uncertain interactions can be compensated even if they are coupled with sensor faults.It is proved that,by using only the corrupted states,all the closed-loop signals are globally uniformly bounded,and the output tracking error converges into an adjustable residual set.Finally,simulation and comparison studies are presented to illustrate the effectiveness of the proposed scheme.
