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This paper focuses on a class of nonlinear switching multi-agent systems about event-triggered adaptive tracking control. Compared with existing results, the event-triggered mechanism is first employed in nonlinear switched multi-agent systems with unknown parameters, and it can reduce the amount of computation and the frequency of the controller updates. By utilizing the backstepping technology, adaptive laws are designed to analyze the unknown parameters. In the sequel, all signals of multi-agent systems are bounded, the tracking errors converge to a small neighborhood of the origin. Finally, simulation results verify the effectiveness of the proposed scheme. [ABSTRACT FROM AUTHOR]

The event‐triggered hybrid control is proposed in this study to realise multi‐model switching when the microgrid system is operating in the island mode. The hybrid control includes decentralised control strategy and coordinated control strategy. Firstly, control commands in the hybrid control strategy are triggered by the event triggering mechanism including trigger events and trigger conditions. When a trigger condition is met, the corresponding event is triggered to execute the corresponding control command. Secondly, the microgrid system is divided into an upper control layer and a lower execution layer by using the multi‐agent system theory. For the upper control layer, a coordinated control strategy based on decision tree algorithm is designed, which can not only issue switching control commands to the lower execution layer, but also reduce the number of switching, improve system stability, and enrich the control strategy. For the lower execution layer, a decentralised control strategy is designed to realise distributed operation of the underlying units. Finally, the model of hybrid automata of each unit is established to ensure the smooth switching of working modes of each unit. The simulation results verify the effectiveness of the event‐triggered hybrid control strategy for controlling the microgrid. [ABSTRACT FROM AUTHOR]

In this study, a two‐hierarchical decentralised coordinated control scheme based on the multi‐agent system (MAS) is proposed to improve the security and the stability of the microgrid. The coordinated switching control strategies are constructed in upper level agent to ensure the microgrid security. The making process of the coordinated switching control strategies is regarded as searching the optimal switching operation mode by means of designing constraint violation function and colour Petri‐net, so that the operation mode of the microgrid can be switched during larger power unbalance. The decentralised continuous control is designed by integrating the outer loop droop controller with the inner loop prescribed performance controller in the lower level unit agents to guarantee its unit system stability. Finally, the simulation results demonstrate the effectiveness of the decentralised coordination control based on MAS. [ABSTRACT FROM AUTHOR]

• A prescribed tracking accuracy containment control scheme for non-affine nonlinear uncertain multi-agent systems is proposed in this paper. In the existing results, the presented strategy just ensure that the containment errors gather to a small neighborhood around the origin. In this note, each containment error can converge to a assigned precision value by the proposed method, and the magnitude of each error can be confirmed precisely before the containment controller is designed. • Two important auxiliary functions are used to help deal with the precision tracking issue. With the aid of these two n-order differentiable functions, the Lyapunov functions can be created. And in combination with adaptive and the backstepping techniques, the technical difficulties of the desire controller design are overcome for non-affine nonlinear uncertain multi-agent systems. • A novel analysis method of containment errors is proposed in this note. By using this method, we can conclude that the convergence error for each agent is a given constant. This paper concentrates on a containment control issue for multi-agent systems in non-affine form with a given accuracy. In comparison with the existing studies on multi-agent systems, precision-based containment control idea is first formulated. With the aid of the proposed strategy, the main merit of this note is that the synchronization errors converge to arbitrary given positive number. Simultaneously, the particular Layapunov functions are constructed by feat of two auxiliary functions. By employing the backstepping and adaptive control technique, the key variables and the actual controller are designed. Unlike the traditional stability analysis, a novel method is used to analyse the convergence of containment errors. In the end, some simulation results demonstrate the correctness for the proposed protocol. [ABSTRACT FROM AUTHOR]

Relative states between neighbors are ubiquitous in large-scale systems, and the relative state saturations need to be considered when designing controllers based on this relative state information. This article investigates the consensus control of the delayed multiagent systems under the relative state saturations. By means of an incidence matrix, the consensus under the relative state saturations is transformed into the stability of edge dynamics operating on constrained sets. To enable the edge states to stay within the constrained sets, a novel nonlinear protocol is designed by embedding an elaborate saturation function. Sufficient conditions are identified, under which not only consensus is achieved but also relative state saturations do not occur. Moreover, this analytical result can address the consensus problem while preserving connectivity, within the limited communication range framework. Simulations illustrate the theoretical results. [ABSTRACT FROM AUTHOR]

This article investigates the consensus tracking of exponentially unstable multiagent systems with time-varying input delay. The truncated predictor feedback approach is utilized for designing delay-dependent state and output feedback protocols. And the explicit conditions that can realize consensus tracking are established in terms of parametric Lyapunov equations and scalar inequalities. Besides, the protocol design algorithms under the maximum allowable delay and the maximum convergence rate are, respectively, provided. Compared with the existing results, the salient characteristic of the current results is to reveal the quantitative relationship among the time delay, unstable plant, network topologies, and the convergence rate. Specifically, for achieving the consensus tracking, the synchronization force from network connectivity needs to dominate the anti-synchronization force from unstable open-loop poles and input delays; the maximum allowable input delay is inversely proportional to the sum of the unstable open-loop poles; the convergence rate becomes smaller as the input delay bounds or/and the sum of the unstable poles in plant increase. Numerical simulations confirm the effectiveness of the proposed theoretical design. [ABSTRACT FROM AUTHOR]

This paper investigates leaderless consensus and leader-following consensus of multiagent systems with Lipschitz nonlinearity and input delay. For such systems, the observer-based truncated prediction feedback protocols are designed via dropping the distributed term and remaining the exponential term of the solution of the system equation over the delay period. Using Lyapunov–Krasovskii functional approach, two sufficient criteria are, respectively, established for achieving leaderless and leader-following consensus. The observer and controller gains are then obtained by means of an iterative linear matrix inequality procedure. A numerical simulation verifies the effectiveness of the proposed control design approach. [ABSTRACT FROM AUTHOR]

Within the framework of multiagent systems, relative information can be directly acquired by vehicle-mounted sensors and the relative information constraints inevitably occur due to limited sensing capabilities. This paper investigates observer-based consensus of nonlinear multiagent systems subject to relative state estimate constraints. Each agent’s state is constructed via a state observer, and the relative state estimate is assumed to be confined into a hypercube. In virtue of the edge Laplacian, the consensus problem of nonlinear multiagent systems under this constraint is converted into the stabilization problem of edge dynamics operating on the constrained set. Observer-based intermittent protocol and adaptive protocol are, respectively, designed for achieving consensus. A convergence analysis is provided with the help of state saturation theory, switched system theory and adaptive theory. Finally, the results on consensus with relate state estimate constraints are applied into the consensus problem while preserving the connectedness, and are validated by a simulation example. [ABSTRACT FROM AUTHOR]