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In this paper, the formation consensus problem for a class of leader–follower networked multi‐agent systems under communication constraints and switching topologies is investigated. A networked predictive control scheme is proposed to achieve stability and output formation consensus with the switching topology, capable of compensating for data loss and time delays in the network. By equating the whole closed‐loop networked multi‐agent system with the proposed control scheme to the corresponding switched system, the sufficient and necessary condition of output formation consensus and stability for agents is given. Finally, using three‐degree‐of‐freedom air‐bearing spacecraft simulators as the control objects, the proposed scheme is demonstrated to be able to actively compensate for the communication constraints through numerical simulations, and it is also verified to have a good control performance by further realizing the formation task of the simulators through practical experiments. [ABSTRACT FROM AUTHOR]

The reliability of the microgrid (MG) can be improved by interconnecting MGs that are in close proximity, because the power shortfall in one MG can be compensated by the excess power available from other interconnected MGs. For multiple dc MG clusters consisting of a large number of heterogeneous distributed generators (DGs), this article establishes a master–slave cooperation framework containing a two-layer voltage estimator. All master-DGs implement current economical allocation among multiple MG clusters and drive their respective slave-DGs to realize current sharing accuracy. Compared with the previous work, the proposed control strategy has the advantages of simultaneous achievement of accurate current sharing and current economical allocation, short time consumption and faster convergence, and robustness against uncertain communication environments. Moreover, all distributed controllers are allowed to be implemented in a variable cyber network, thus well matching the characteristics of frequent switching operation in MG systems. Sufficient conditions in terms of control time constants for the two-layer cyber network are also deduced to ensure entire system stability. Different cases are tested to verify the effectiveness of the results in MATLAB/SimPowerSystems. [ABSTRACT FROM AUTHOR]

This brief investigates the consensus for networked delayed multi-agent systems with switching topologies and time-varying communication delays. Novel consensus protocol that uses (pseudo) predictive scheme is proposed to synchronize the states of agents. Sufficient consensus conditions are derived, and the results show that the state consensus can be guaranteed if the graphs contain a joint spanning tree as frequently as the system evolves and no eigenvalues of system matrix exist outside the unit circle. Numerical examples illustrate the theoretic results. [ABSTRACT FROM AUTHOR]

To improve the poor dynamic consensus in multiple dc–dc converter systems caused by parameter differences, this article proposes a global optimal cooperative control strategy. The proposed control strategy achieves dynamic consensus of output currents by minimizing a global performance index, which consists of local errors and neighbor synchronization errors. In this system, each converter is regarded as an agent in the communication digraph, so as to construct a cyber-physical model. Accordingly, a cooperative control method based on the linear quadratic regulator (LQR) is proposed, with the help of nonlinear coordinate transformation techniques. Different from conventional LQR, integral action is introduced to eliminate steady-state errors and improve coordinated performance. Meanwhile, the proof of the stability and consensus of the closed-loop system is given using Lyapunov approach. Moreover, the design guidelines to tune the dynamic response are provided through simulations. The experimental results further demonstrate the effectiveness and superiority of the proposed control method in a multiconverter prototype. [ABSTRACT FROM AUTHOR]

The problem of leader–following consensus is investigated for heterogeneous discrete‐time linear networked multi‐agent systems with data packet losses and network delays. Two kinds of networked protocols are presented to derive the states of followers to reach an agreement on leader's state under the switching topologies, in the meanwhile, the asymptotic stability of all agents are guaranteed. Due to unavailable agents' states and communication constraints, the networked predictive control method is used to compensate network delays and data packet losses actively. Sufficient criteria of leader–following consensus and asymptomatic stability are obtained when at least one follower is connected to the leader by a directed edge. The simulation example is presented to illustrate that states of followers can track leader's state, and all agents' states also asymptotically converge to the equilibrium under the proposed theoretical results. [ABSTRACT FROM AUTHOR]

This paper investigates the control problem of networked nonlinear multiagent systems with communication constraints and unknown dynamics, based on system input–output data. A cost function for the design of networked nonlinear multiagent control systems is presented, which considers not only the coordination performance between agents but also the performance of individual agents. Utilizing a data model to represent discrete-time nonlinear multiagent systems, a networked data-driven predictive control scheme is proposed to optimize control performance, compensate for communication constrains, and achieve both consensus and stability of networked nonlinear multiagent systems. An optimal control protocol is derived, which minimizes the cost function and makes compensation for communication constraints. The criteria of achieving both consensus and stability of networked nonlinear multiagent systems are provided. An example illustrates the performance of the proposed networked data-driven predictive control scheme. [ABSTRACT FROM AUTHOR]

In this brief, the coordinated path-following control for multiple nonlinear autonomous vehicles connected by digital networks is studied. To compensate for the time delays of the network actively, a novel networked predictive control strategy is proposed. Compared with existing networked control strategies, the control strategy proposed in this brief admits advantages such as high computational efficiency, robustness to disturbances, and relaxed restriction on the communication topology. The theoretical analysis of the proposed method is given and the conditions to achieve the control objectives are derived. Finally, the experiments are implemented to validate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This article examines the complex issue of coordinating networked multi-agent control systems through distributed cloud computing, with a specific focus on compensating for time-varying transmission delays using a predictive control scheme. Unlike the general approach, which treats the time-varying delays as a constant at their maximum value, this paper aims to minimize transmission delays as much as possible. This objective leads to a consensus problem characterized by a time-varying upper-triangular topology. In this study, stability criteria are established to ensure the stability of the time-varying error systems, and a simultaneous similar method is proposed to facilitate feedback designation. The effectiveness of the devised scheme is demonstrated through illustrative examples. [ABSTRACT FROM AUTHOR]

This paper investigates consensus problems of networked linear time invariant (LTI) multi‐agent systems, subject to variable network delays and switching topology. A new protocol is proposed for such systems with matrix B that has full row rank, based on stochastic, indecomposable, aperiodic (SIA) matrix and the predictive control scheme. With the predictive scheme the network delay is compensated. Consensus analysis based on the seminorm is provided. The conditions are obtained for such systems with periodic switching topology to reach consensus. The proposed protocol can deal with time‐varying delays, switching topology, and an unstable mode. The numerical examples demonstrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

This study investigates the output consensus problem for a class of non‐linear networked multi‐agent systems with switching topology and time‐varying delays. To synchronise the outputs of the agents, novel distributed data‐driven consensus protocols are proposed, where the reference input is designed to be the time‐varying average of the agents' output. To avoid the self‐tracking phenomenon, the delayed information is introduced in the protocol. The proposed methods merely depend on the input and output data of the neighbouring agents, without using explicit or implicit information of its mathematical model. Sufficient conditions are derived to guarantee the closed‐loop stability and consensus, with the convergence rate obtained. Numerical and practical examples are conducted to demonstrate the effectiveness of the proposed protocols. [ABSTRACT FROM AUTHOR]

This paper focuses on the admissible consensus problem for heterogeneous descriptor multi-agent systems. Based on algebra, graph and descriptor system theory, the necessary and sufficient conditions are proposed for heterogeneous descriptor multi-agent systems achieving admissible consensus. The provided conditions depend on not only the structure properties of each agent dynamics but also the topologies within the descriptor multi-agent systems. Moreover, an algorithm is given to design the novel consensus protocol. A numerical example demonstrates the effectiveness of the proposed design approach. [ABSTRACT FROM AUTHOR]

In this study, the containment control problems in second‐order multi‐agent systems for both static leaders and dynamic leaders under directed topologies are studied. The authors propose the impulsive containment control algorithms without using velocity measurements. Some necessary and sufficient conditions depending on the eigenvalues of the Laplacian matrix associated with the communication graph, the impulsive period and the gain parameters, are obtained to guarantee the containment control. Then, the containment control of multi‐agent systems with input delay using impulsive algorithms is investigated. Also, some necessary and sufficient conditions are given. Finally, some simulations are conducted to verify the effectiveness of the proposed algorithms. [ABSTRACT FROM AUTHOR]

This paper investigates the global bounded consensus problem of networked multiagent systems consisting of nonlinear nonidentical node dynamics with the communication time-delay topology. We derive globally bounded controlled consensus conditions for both delay-independent and delay-dependent conditions based on the Lyapunov–Krasovskii functional method. The proposed consensus criteria ensure that all agents eventually move along the desired trajectory in the sense of boundedness. Meanwhile, the bounded consensus criteria can be viewed as an extension of the case of identical agent dynamics to the case of nonidentical agent dynamics. We finally demonstrate the effectiveness of the theoretical results by means of a numerical simulation. [ABSTRACT FROM PUBLISHER]

The consensus problem of discrete-time networked multi-agent systems (NMASs) with a communication delay is investigated in this article, where the dynamics of agents described by discrete-time linear time-invariant systems can be either uniform or non-uniform. For the NMASs with a directed topology and constant delay, a novel protocol based on the networked predictive control scheme is proposed to compensate for communication delay actively. Using algebraic graph theories and matrix theories, necessary and/or sufficient conditions of achieving consensus are obtained, which indicates that, under the proposed protocol, the consensus is independent of the network delay and only dominated by agents' dynamics and communication topology. Meanwhile, the protocol design and consensus analysis are also presented in the case of no network delay. Simulation results are further presented to demonstrate the effectiveness of theoretical results. [ABSTRACT FROM AUTHOR]

In this paper, the design problem of recursive state estimator is discussed for a class of coupled nonlinear dynamical networks with randomly switching topologies and multiple missing measurements under the event-triggered mechanism. A sequence of random variables obeying the Bernoulli distribution with certain occurrence probabilities is adopted to model the multiple missing measurements and the random change manners of the network topologies. The event-based communication protocol is introduced to adjust the transmission frequency, thereby improving the energy utilization efficiencies of the communication networks. The objective of the addressed variance-constrained estimation problem is to construct a recursive state estimator such that, in the simultaneous presence of event-based transmission strategy, randomly switching topologies as well as multiple missing measurements, a locally optimal upper bound is guaranteed on the estimation error covariance by properly determining the estimator gain, where the desired estimator gain matrix is formulated via the solutions to certain recursive matrix equations. Besides, theoretical analysis is conducted on the monotonicity regarding the missing probabilities of degraded measurements and the obtained upper bound matrix. Finally, some simulations with comparisons are carried out to demonstrate the effectiveness and feasibility of proposed event-triggered state estimation method. [ABSTRACT FROM AUTHOR]