Accepted version of an article from the journal: Nonlinear Dynamics and Systems Theory. Also available from the publisher: http://www.e-ndst.kiev.ua/v9n3.htm
To effectively use the network resources, a suitable event-driven communication scheme is proposed for the networked switched systems in this paper. Under the EDCS, a finite-time filter is designed for switched systems, which does not synchronize with the switched systems. Different from the existing finite-time problems, finite-time boundedness (FTBs) and input-output finite-time stability (IO-FTSy) are simultaneously considered in this paper. Some sufficient conditions are established to check the properties of the FTBs and the IO-FTSy of the event-driven asynchronous filtering error system by constructing a reasonable Lyapunov-Krasovskii functional and using the average dwell time approach. All the matrix inequalities can be converted to linear matrix inequalities so as to design the event-driven asynchronous filter. The applicability of the proposed filtering scheme is demonstrated via a mass-spring system model.
With the rapid technological development of machines in different applications such as vehicles, robotics, and manufacturing, concerns may arise with regard to complexity, safety, performance, and maintenance costs associated with the machine operation [...]
Distributed control systems for vibration control of large structures involve a large number of actuation devices and sensors that work coordinately to produce the desired control actions. Design strategies based on linear matrix inequality (LMI) formulations allow obtaining controllers for these complex control problems, which are characterized by large dimensionality, high computational cost and severe information constraints. In this paper, we conduct a comparative study of the computational effectiveness of three different LMI-based controller design strategies: H-infinity, energy-to-peak and energy-to-componentwise-peak. The H-infinity approach is a well-known design methodology and has been widely used in the literature. The energy-to-peak approach is a particular case of generalized H2 design that is gaining a growing relevance in structural vibration control. Finally, the energy-to-componentwise-peak approach is a less common case of generalized H2 design that produces promising results among the three considered approaches. These controller design strategies are applied to synthesize active state-feedback controllers for the seismic protection of a five-story building and a twenty-story building both equipped with complete systems of interstory actuation devices. To evaluate the computational effectiveness of the proposed LMI design methodologies, the corresponding computation times are compared and a suitable set of numerical simulations is carried out to assess the performance of the obtained controllers. As positive results, two main facts can be highlighted: the computational effectiveness of the energy-to-peak control design strategy and the particularly well-balanced behavior exhibited by the energy-to-componentwise-peak controllers. On the negative side, it has to be mentioned the computational inefficiency of the considered LMI design methodologies to properly deal with very-large-scale control problems.
This paper is concerned with the problems of finite-time stability (FTS) and finite-time stabilisation for a class of nonlinear systems with time-varying delay, which can be represented by Takagi–Sugeno fuzzy system. Some new delay-dependent FTS conditions are provided and applied to the design problem of finite-time fuzzy controllers. First, based on an integral inequality and a fuzzy Lyapunov–Krasovskii functional, a delay-dependent FTS criterion is proposed for open-loop fuzzy system by introducing some free fuzzy weighting matrices, which are less conservative than other existing ones. Then, the parallel distributed compensation controller is designed to ensure FTS of the time-delay fuzzy system. Finally, an example is given to illustrate the effectiveness of the proposed design approach.
In this note, the problems of stability analysis and controller synthesis of Markovian jump systems with time-varying delay and partially known transition rates are investigated via an input–output approach. First, the system under consideration is transformed into an interconnected system, and new results on stochastic scaled small-gain condition for stochastic interconnected systems are established, which are crucial for the problems considered in this paper. Based on the system transformation and the stochastic scaled small-gain theorem, stochastic stability of the original system is examined via the stochastic version of the bounded realness of the transformed forward system. The merit of the proposed approach lies in its reduced conservatism, which is made possible by a precise approximation of the time-varying delay and the new result on the stochastic scaled small-gain theorem. The proposed stability condition is demonstrated to be much less conservative than most existing results. Moreover, the problem of stabilization is further solved with an admissible controller designed via convex optimizations, whose effectiveness is also illustrated via numerical examples. Copyright © 2015 John Wiley & Sons, Ltd.
Dynamic voltage restorer (DVR) can preserve a sensitive load against electrical distribution system interruption. After connecting DVR to the system, voltage sag is quickly resolved and no voltage oscillation caused by malfunction of sensitive loads occur. When there is a high voltage sag in distribution or transmission, in order to compensate voltage to the value before fault, both reactive compensation and active power compensation should be performed which requires a DC source in DC link of power quality compensators; if there is only one capacitor in DC link, only reactive power compensation can be performed, as a result significant voltage drops cannot be modified. Distributed generation sources like photovoltaic (PV) can be used as a battery instead of DC link supply of D-FACTS devices due to DC nature of their output voltage. Performance of DVR in modifying power quality indices depends on performance of its control system. In this paper, a fuzzy adaptive controller is used instead of the conventional PI controller in the control system of the DVR-PV hybrid compensator to improve its performance in compensating voltage interruption and different types of voltage sag. DVR based on fuzzy controller performs better than DVR based on other controllers like PI. Simulation of electrical distribution system is done in the presence of DVR based on fuzzy-adaptive control scheme and PV using Matlab/Simulink.
No abstract is provided for this article.
No abstract is provided for this article.
The primary objective of this chapter is to provide readers with a comprehensive understanding of the historical origins and fundamental concepts of fractional calculus theory. It endeavors to delve into the intricate interplay between fractional calculus and its practical applications, particularly focusing on the implementation of fractional sliding mode control theory and event-triggered mechanisms across a diverse array of fractional-order systems. These systems encompass fractional-order chaotic systems, fractional-order coupled systems, and fractional-order multi-agent systems. Through an in-depth exploration of fractional sliding mode control design principles, the chapter aims to elucidate how these advanced methodologies can be effectively applied. Additionally, the chapter offers a curated selection of references to pertinent literature, aimed at enriching the scholarly discourse and stimulating further exploration in the field.
No abstract is provided for this article.
This paper is concerned with the problem of sampled-data exponential synchronization for chaotic Lur'e systems (CLSs) in the form of master-slave framework. An improved time-dependent Lyapunov functional (TDLF) is put forward to fully exploit the accessible information about sampling characteristics and nonlinearities of the CLS. By resorting to the improved TDLF, a new synchronization criterion is established, which ensures the synchronization error system is globally exponentially stable. An illustrative example is offered to demonstrate the validity and virtue of the proposed design methodology.
This paper is concerned with finite-time sliding mode control (SMC) of continuous-time semi-Markovian jump systems with immeasurable premise variables via fuzzy approach. First, an integral sliding surface is constructed based on fuzzy observer. Second, an observer-based SMC law is synthesized to guarantee finite-time reachability of the predefined sliding surface before the prescribed time. Third, through finite-time boundedness analysis, the required boundedness performance is conducted at the reaching phase first and then the sliding motion phase, respectively. Furthermore, sufficient conditions in terms of linear matrix inequalities (LMIs) are established to guarantee the required boundedness performance of the overall closed-loop controlled system during the two phases with generally uncertain transition rates (TRs) simultaneously. Finally, a practical example is given to show the validity of the established method numerically.
This paper is concerned with the network-based fault detection problem for a class of nonlinear discrete-time networked control systems with multiple communication delays and bounded disturbances. First, a sliding mode based nonlinear discrete observer is proposed. Then the sufficient conditions of sliding motion asymptotical stability are derived by means of the linear matrix inequality (LMI) approach on a designed surface. Then a discrete-time sliding-mode fault observer is designed that is capable of guaranteeing the discrete-time sliding-mode reaching condition of the specified sliding surface. Finally, an illustrative example is provided to show the usefulness and effectiveness of the proposed design method.
No abstract is provided for this article.
This paper deals with the problem of robust stability and robust stabilization for a class of continuous-time singular Takagi–Sugeno fuzzy systems. Sufficient conditions on stability and stabilization are proposed in terms of strict LMI (Linear Matrix Inequality) for uncertain T–S fuzzy models. In order to reduce the conservatism of results developed using quadratic method, an approach based on non-quadratic Lyapunov functions and S-procedure is proposed. Illustrative examples are given to show the effectiveness of the given results.
The performance of receiver, transmitter, and joint transmitter/receiver antenna array processing for interference nulling and diversity over fading radio links are compared and contrasted in this paper. Specific examples of linear and non-linear algorithms are considered in this context. To perform transmitter processing, a priori knowledge of the radio propagation channel is required at the transmitter. This is typically achieved by the provision of a feedback loop that supplies the transmitter with the channel state information (CSI). The impact on transmitter processing of non-zero delays in the CSI feedback loop is quantified in this paper. It is assumed that channel estimation is performed with perfect accuracy at the receiver, and that the feedback loop is error-free. It is shown that while transmitter processing out performs receiver processing at low relative Doppler frequencies, its performance degrades rapidly when the CSI feedback delay is greater than 2% of the channel coherence time. The results presented can be readily interpreted in the context of multi-user uplink and downlink in cellular systems, or collaborative signal processing among base stations.
