Continuous control protocols are extensively utilized in traditional MASs,in which information needs to be transmitted among agents consecutively,therefore resulting in excessive consumption of limited resources.To de...Continuous control protocols are extensively utilized in traditional MASs,in which information needs to be transmitted among agents consecutively,therefore resulting in excessive consumption of limited resources.To decrease the control cost,based on ISC,several LFC problems are investigated for second-order MASs without and with time delay,respectively.Firstly,an intermittent sampled controller is designed,and a sufficient and necessary condition is derived,under which state errors between the leader and all the followers approach zero asymptotically.Considering that time delay is inevitable,a new protocol is proposed to deal with the time-delay situation.The error system’s stability is analyzed using the Schur stability theorem,and sufficient and necessary conditions for LFC are obtained,which are closely associated with the coupling gain,the system parameters,and the network structure.Furthermore,for the case where the current position and velocity information are not available,a distributed protocol is designed that depends only on the sampled position information.The sufficient and necessary conditions for LFC are also given.The results show that second-order MASs can achieve the LFC if and only if the system parameters satisfy the inequalities proposed in the paper.Finally,the correctness of the obtained results is verified by numerical simulations.展开更多
This paper conducts a survey on iterative learn-ing control(ILC)with incomplete information and associated control system design,which is a frontier of the ILC field.The incomplete information,including passive and ac...This paper conducts a survey on iterative learn-ing control(ILC)with incomplete information and associated control system design,which is a frontier of the ILC field.The incomplete information,including passive and active types,can cause data loss or fragment due to various factors.Passive incomplete information refers to incomplete data and information caused by practical system limitations during data collection,storage,transmission,and processing,such as data dropouts,delays,disordering,and limited transmission bandwidth.Active incomplete information refers to incomplete data and information caused by man-made reduction of data quantity and quality on the premise that the given objective is satisfied,such as sampling and quantization.This survey emphasizes two aspects:the first one is how to guarantee good learning performance and tracking performance with passive incomplete data,and the second is how to balance the control performance index and data demand by active means.The promising research directions along this topic are also addressed,where data robustness is highly emphasized.This survey is expected to improve understanding of the restrictive relationship and trade-off between incomplete data and tracking performance,quantitatively,and promote further developments of ILC theory.展开更多
Time delay is an inherent characteristic of real-world phenomena which may affect the system's characteristic.The systems including delay are known as time-delay systems,they are represented using delay differenti...Time delay is an inherent characteristic of real-world phenomena which may affect the system's characteristic.The systems including delay are known as time-delay systems,they are represented using delay differential equations.Modeling,discretisation,stability and control design for time-delay systems are still challenging in modern control theory.This paper systematically overviews available discretisation methods of linear and nonlinear time-delay systems.Emphasis is placed on illustrating fundamental results and recent progress on discretisation methods for delay systems.Numerous methods for the discretisation of linear and nonlinear systems considering input delays,state or output delays in the system's dynamics have been presented.A particular attention will be paid to illustrate effects of the discretisation process on the stability of discretised systems.Examples of mathematical descriptions,problems,and performance analysis for delay systems are presented.The presentation of discretisation methods is as easy as possible,focussing more on the main ideas and mathematical concepts by analogy.Finally,some possible future research directions to be tackled by researchers in this field are discussed.展开更多
The main aim of this work is to design a non-fragile sampled data control(NFSDC) scheme for the asymptotic synchronization criteria for interconnected coupled circuit systems(multi-agent systems, MASs). NFSDC is used ...The main aim of this work is to design a non-fragile sampled data control(NFSDC) scheme for the asymptotic synchronization criteria for interconnected coupled circuit systems(multi-agent systems, MASs). NFSDC is used to conduct synchronization analysis of the considered MASs in the presence of time-varying delays. By constructing suitable Lyapunov functions, sufficient conditions are derived in terms of linear matrix inequalities(LMIs) to ensure synchronization between the MAS leader and follower systems. Finally, two numerical examples are given to show the effectiveness of the proposed control scheme and less conservation of the proposed Lyapunov functions.展开更多
This paper presents the sampling and feedback control techniques, which are the kernel of our experiment on adaptive Polarization Mode Dispersion (PMD) compensation for optical fiber communication systems. Some key po...This paper presents the sampling and feedback control techniques, which are the kernel of our experiment on adaptive Polarization Mode Dispersion (PMD) compensation for optical fiber communication systems. Some key points on sampling and feedback techniques are discussed and practical resolutions for them are put forward.展开更多
This paper investigates stability problem of DC micro-grid under disturbance.Tracking control based on the sampled H∞controller is designed for solving such problem.First,it sets up the model of the DC micro-grid wit...This paper investigates stability problem of DC micro-grid under disturbance.Tracking control based on the sampled H∞controller is designed for solving such problem.First,it sets up the model of the DC micro-grid with the energy storage unit.Next,it presents the model for the closed-loop control system and the design method for the sampled state feedback controller.Then,it gives the sampled H∞performance analysis by considering the sampled quantisation error as an external disturbance term of the system.It derives one sufficient condition for stabilisation of the DC micro-grid based on linear matrix inequalities and Lyapunov theory.Finally,simulations verify the validity of our results.展开更多
In this paper, finite sample properties of virtual reference feedback tuning control are considered, by using the theory of finite sample properties from system identification. To design a controller in closed loop sy...In this paper, finite sample properties of virtual reference feedback tuning control are considered, by using the theory of finite sample properties from system identification. To design a controller in closed loop system structure, the idea of virtual reference feedback tuning is proposed to avoid the identification process corresponding to the plant model. After constructing one identification cost without any knowledge of plant model, the author derives one bound on the difference between the expected identification cost and its sample identification cost under the condition that the number of data points is finite. Also the correlation between the plant input and external noise is considered in the derivation of this bound. Furthermore, the author continues to derive one probability bound to quantify this difference by using some probability inequalities and control theory.展开更多
基金supported by the National Natural Science Foundation of China under Grants 62476138 and 42375016.
文摘Continuous control protocols are extensively utilized in traditional MASs,in which information needs to be transmitted among agents consecutively,therefore resulting in excessive consumption of limited resources.To decrease the control cost,based on ISC,several LFC problems are investigated for second-order MASs without and with time delay,respectively.Firstly,an intermittent sampled controller is designed,and a sufficient and necessary condition is derived,under which state errors between the leader and all the followers approach zero asymptotically.Considering that time delay is inevitable,a new protocol is proposed to deal with the time-delay situation.The error system’s stability is analyzed using the Schur stability theorem,and sufficient and necessary conditions for LFC are obtained,which are closely associated with the coupling gain,the system parameters,and the network structure.Furthermore,for the case where the current position and velocity information are not available,a distributed protocol is designed that depends only on the sampled position information.The sufficient and necessary conditions for LFC are also given.The results show that second-order MASs can achieve the LFC if and only if the system parameters satisfy the inequalities proposed in the paper.Finally,the correctness of the obtained results is verified by numerical simulations.
基金supported by the National Natural Science Foundation of China(61673045)Beijing Natural Science Foundation(4152040)
文摘This paper conducts a survey on iterative learn-ing control(ILC)with incomplete information and associated control system design,which is a frontier of the ILC field.The incomplete information,including passive and active types,can cause data loss or fragment due to various factors.Passive incomplete information refers to incomplete data and information caused by practical system limitations during data collection,storage,transmission,and processing,such as data dropouts,delays,disordering,and limited transmission bandwidth.Active incomplete information refers to incomplete data and information caused by man-made reduction of data quantity and quality on the premise that the given objective is satisfied,such as sampling and quantization.This survey emphasizes two aspects:the first one is how to guarantee good learning performance and tracking performance with passive incomplete data,and the second is how to balance the control performance index and data demand by active means.The promising research directions along this topic are also addressed,where data robustness is highly emphasized.This survey is expected to improve understanding of the restrictive relationship and trade-off between incomplete data and tracking performance,quantitatively,and promote further developments of ILC theory.
文摘Time delay is an inherent characteristic of real-world phenomena which may affect the system's characteristic.The systems including delay are known as time-delay systems,they are represented using delay differential equations.Modeling,discretisation,stability and control design for time-delay systems are still challenging in modern control theory.This paper systematically overviews available discretisation methods of linear and nonlinear time-delay systems.Emphasis is placed on illustrating fundamental results and recent progress on discretisation methods for delay systems.Numerous methods for the discretisation of linear and nonlinear systems considering input delays,state or output delays in the system's dynamics have been presented.A particular attention will be paid to illustrate effects of the discretisation process on the stability of discretised systems.Examples of mathematical descriptions,problems,and performance analysis for delay systems are presented.The presentation of discretisation methods is as easy as possible,focussing more on the main ideas and mathematical concepts by analogy.Finally,some possible future research directions to be tackled by researchers in this field are discussed.
基金Project supported by the National Natural Science Foundation of China(No.62103103)the Natural Science Foundation of Jiangsu Province,China(No.BK20210223)。
文摘The main aim of this work is to design a non-fragile sampled data control(NFSDC) scheme for the asymptotic synchronization criteria for interconnected coupled circuit systems(multi-agent systems, MASs). NFSDC is used to conduct synchronization analysis of the considered MASs in the presence of time-varying delays. By constructing suitable Lyapunov functions, sufficient conditions are derived in terms of linear matrix inequalities(LMIs) to ensure synchronization between the MAS leader and follower systems. Finally, two numerical examples are given to show the effectiveness of the proposed control scheme and less conservation of the proposed Lyapunov functions.
文摘This paper presents the sampling and feedback control techniques, which are the kernel of our experiment on adaptive Polarization Mode Dispersion (PMD) compensation for optical fiber communication systems. Some key points on sampling and feedback techniques are discussed and practical resolutions for them are put forward.
基金The work was supported by the Natural Science Foundation of China[grant numbers 61673188,61603212,61761130081 and 61876097]the Foundation for Innovative Research Groups of Hubei Province of China[grant number 2017CFA005]+1 种基金the Fundamental Research Funds for the Central Universities of HUST[grant number 2018KFYXKJC051]the Research Funds for Hubei Key Laboratory of Applied Mathematics(Hubei University).
文摘This paper investigates stability problem of DC micro-grid under disturbance.Tracking control based on the sampled H∞controller is designed for solving such problem.First,it sets up the model of the DC micro-grid with the energy storage unit.Next,it presents the model for the closed-loop control system and the design method for the sampled state feedback controller.Then,it gives the sampled H∞performance analysis by considering the sampled quantisation error as an external disturbance term of the system.It derives one sufficient condition for stabilisation of the DC micro-grid based on linear matrix inequalities and Lyapunov theory.Finally,simulations verify the validity of our results.
基金supported by Jiangxi Provincial National Science Foundation under Grant No.20142BAB206020
文摘In this paper, finite sample properties of virtual reference feedback tuning control are considered, by using the theory of finite sample properties from system identification. To design a controller in closed loop system structure, the idea of virtual reference feedback tuning is proposed to avoid the identification process corresponding to the plant model. After constructing one identification cost without any knowledge of plant model, the author derives one bound on the difference between the expected identification cost and its sample identification cost under the condition that the number of data points is finite. Also the correlation between the plant input and external noise is considered in the derivation of this bound. Furthermore, the author continues to derive one probability bound to quantify this difference by using some probability inequalities and control theory.
