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Abstract This work deals with the robustness analysis of LPV (Linear Parameter-Varying) systems. The degree of robustness of a system makes possible to know if the defined level of performance is guaranteed or not. The robustness of a system is characterized by its capacity to reject perturbations, by criterion of speed, of precision or by taking into account a certain degree of imprecision of the model, often introduced during a necessary phase of linearization. It is then necessary to manipulate relatively sophisticated models in order to take all these parameters into account. The representation of the LPV systems is such a sophisticated modeling. Fuzzy Takagi–Sugeno, polytopic and norm-bounded representations are often used to describe the behavior of nonlinear dynamics of the system. This paper proposes a generic model that encompasses these representations (fuzzy TS, polytopic and norm-bounded). This generic model is denoted uncertain BPV (Bi-linear Parameter Varying). A robustness analysis technique, allowing the generation of a robustness criterion, is then proposed. It can be applied to the case of state or output feedback, as well as to paremeter-dependent controllers. The concept of D -stability is considered and the tools are expressed in terms of LMI. [ABSTRACT FROM AUTHOR]

This paper presents an intelligent strategy for optimal power management of stand-alone hybrid system. The designed management strategy aims at regulating the power flow between the generated and the consumed powers of a wind/solar/battery stand-alone system in order to satisfy the load (one family house). The chosen strategy considers the wind generator ( WG ) and the photovoltaic panel ( PV )as the main energy sources and the battery bank ( BS) as storage system. For the power source emergency, it uses the diesel engine ( DE ) as an additional source. Indeed, the optimal management strategy consists of generating power references for each subsystem. Based on the prediction of weather conditions, these power references are generated with taking into account some constraints related to the reliability of each subsystem. In order to validate the proposed strategy under real situations, measurements of the weather conditions and the power consumption data of an individual house are considered. The simulation results are highlighted to demonstrate the feasibility of our approach. [ABSTRACT FROM AUTHOR]

In this paper, fault tolerant saturated control (FTSC) problem for discrete-time T–S fuzzy systems with delay is studied. Sufficient conditions for observer based control design with saturation constraints are developed. Based on a multiple Lyapunov functions and the slack variables, design conditions are formulated in LMI terms using the cone complementarity technique. The obtained results are illustrated on a numerical example showing fault detection, its localization and reconfiguration of the control law to maintain asymptotic stability even in the presence of both permanent sensor faults and saturation on the control. [ABSTRACT FROM AUTHOR]

The topology based on permanent magnet generator (PMSG) and diode bridge rectifier is frequently used in small wind energy conversion system since it is robust and easy to control. This paper presents a robust control for the wind conversion system based on PMSG and boost DC/DC converter in the aim to maintain the generator rectified voltage at a reference voltage corresponding to the reference power imposed by the supervisory module. The reference power control is guaranteed without measuring the wind speed. The sufficient conditions for state feedback stabilizing designed controller are given in terms of solutions to a linear matrix inequality (LMI) and H ∞ . Simulation tests results are carried out for this wind conversion system topology which operates in a multi-source system, in order to visualize the feasibility of the proposed method. [ABSTRACT FROM AUTHOR]

Abstract: This paper proposes an H ∞ robust static output fuzzy controller for dc–dc converters using Takagi–Sugeno fuzzy models. In the proposed approach, the controller is designed using the output voltage which is the measured signal. Therefore, the number of sensors does not increase in comparison with traditional approaches. In addition, the proposed controller is designed to not only ensure a good reference tracking with disturbance rejection, but also provide the robustness with respect to the input voltage and load variations. The asymptotic tracking of signal is guaranteed, in the Lyapunov sense, by satisfying some sufficient conditions given in Linear Matrix Inequality form. Numerical examples show the good steady-state and dynamic behaviors. [Copyright &y& Elsevier]

This paper investigates the robust asymptotic stability analysis and the output feedback stabilization problems for a class of uncertain discrete-time switched TS fuzzy systems with immeasurable states and time-varying delays. By utilizing Generalized JSH -transformation and Rouchés’ theorems, delay-sufficient conditions are developed for achieving the mission of reducing conservatism and to break with existing ones which are formulated in terms of linear matrix inequalities (LMIs). Then, a switched TS fuzzy state observer is designed to obtain the estimations of the unmeasured states. Lastly, one comparative example and a practical example are given to illustrate the effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]