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This paper deals with the problem of adaptive fuzzy control for a class of nonlinear uncertain systems with hysteresis input. Fuzzy logic systems are employed to approximate the unknown nonlinear behaviors, and the sliding mode technique is used to synthesize an adaptive fuzzy controller. A proportional integral control term is adopted to reduce the chattering phenomenon engendered by both sliding mode control technique and hysteretic characteristic of the system. The proposed control scheme ensures the boundedness of all closed-loop signals, and forces the tracking error to converge to zero. The main contribution of this work is the development of a control strategy for a class of nonlinear hysteretic systems subject to external disturbances and uncertainties. Two case studies are given to illustrate and to prove the effectiveness of the presented approach.

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This study provides an adaptive fuzzy control scheme for the class of nonlinear uncertain strict-feedback systems with external disturbances. The backstepping and synergetic control theories are used to develop a robust control approach for this class of systems. The unknown behaviors of the system are estimated through fuzzy systems. The stability is analyzed using the Lyapunov method, which shows that the proposed control method ensures that all the signals of the closed-loop system are bounded, and the tracking error converges approximately to zero. Two simulation examples are given to demonstrate the efficiency of the developed control approach.

This paper deals with the stabilization of DC/DC boost converter and the nonlinear phenomena elimination using a constrained Backstepping technique. Based on the converter averaged model, the pro- posed control approach is designed and the input to state stability concept is used to proof the system global stability. Furthermore, the structural stability is proven to show the efficiency of the proposed approach to suppress the nonlinear phenomena exhibited by the converter. The simulation results illustrate the different regions of stability of the system and the bifurcation diagrams are given to show the effectiveness of the proposed approach in terms of nonlinear phenomena suppression.

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In this paper, we investigate a competitive Multilevel Inverter (MLI) named by Packed U Cell (PUC). This converter is capable to generate more levels with fewer components compared with existing MLI topologies. The system consists of a PV arrays supply connected to a single-phase PUC5 inverter. A boost converter is employed to extract the Maximum Power (MPP) controlled by an MPP tracking (MPPT) algorithm. Then, A nonlinear control strategy with Pulse Width Modulation (PWM) is used to control the 5-level PUC (PUC5) to ensure good tracking and high-quality convention. Some simulations were performed in MATLAB/SIMULINK to demonstrate the effectiveness of this topology with the proposed control scheme.

The aim of this paper is to construct an adaptive fuzzy controller for strict feedback nonlinear uncertain disturbed systems. The backstepping and synergetic control techniques are combined to develop a robust controller for the considered class of systems. In this paper, fuzzy systems are utilized to estimate the unknown behaviors of the system. The proposed approach guarantees that all signals in the closed-loop adaptive control system are semi-globally uniformly ultimately bounded, and the tracking error eventually converges to a small neighbourhood of the origin. Numerical simulations are provided to show the effectiveness of the presented control technique.

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The nonlinear hysteretic behavior exists in many systems and makes their analysis and control an arduous task. Based on adaptive fuzzy synergetic control strategy, this paper deals with the control of a class of nonlinear systems preceded by an unknown backlash nonlinearity. Fuzzy logic systems are used to estimate the unknown nonlinear behaviors of the system, and a novel adaptive fuzzy controller is designed via synergetic control theory. Stability is proven, theoretically, in the sense of bounded closed-loop signals, and a tracking error converges to the origin. Simulation results validate the proposed approach and give an overview on the achieved tracking performances.

The paper deals with the problem of switched dynamical systems modeling especially in DC-DC converters case study consideration. It presents two approaches to describe accurately the behavior of this class of systems. To clarify the paper's contribution, the proposed approaches are validated through simulations and experimental results. A comparative study, between the obtained results and those of other techniques from the literature, is given to evaluate the performances of the studied approaches.

The main objective of this paper lies in providing a control strategy for a class of nonlinear hysteretic systems in presence of external disturbances and system uncertainties. Fuzzy logic systems are utilized to approximate the unknown nonlinear behaviors and sliding mode technique is used to construct an adaptive controller. The proposed control scheme ensures that all signals in the closed-loop system are bounded, and the tracking error eventually converges to a small neighborhood of the origin. Simulation results are provided to illustrate the efficiency of the suggested approach.

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This paper introduces a recursive identification methods toolbox (called RIM) running under Matlab environment for dynamic system identification from available data. The RIM includes many methods which are generally used. The RIM helps users to validate the theoretical results and to carry out comparison between identifications methods without the need of algorithms programming. Furthermore, the RIM can be used as an education platform to study the identification parameters effect on model validity and results accuracy. To show its performance and capability, the RIM is evaluated through many application examples.

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The modeling process presents a key step on the analysis and the control of DC–DC converters that can exhibit complicated nonlinear phenomena. In order to describe accurately the converter behavior, a discrete modeling technique is proposed; it allows the exact description of the system with a minimum of simplifying assumptions and validity hypothesis of the mode. The validation of the proposed method is achieved through simulation and comparative study results using some criteria such as the approximation error, computing time and allocated memory for data processing and storage.

DC–DC converters are an important element in photovoltaic systems to attain desired level of energy and to shape it according to the demand. This paper proposes new optimized sliding mode controller (SMC) with fixed switching frequency for a boost converter to step up a fluctuating solar panel voltage to a higher constant DC voltage. Based on the converter functioning principle, a sliding mode controller (SMC) is proposed. Then, a method for SMC parameters selection using simplex and PSO techniques is given. The simplex method allows obtaining the admissible ranges for SMC parameters while taking into account practical considerations about the converter. Then, theses ranges will be used by the particle swarm optimization technique (PSO) to find optimal values for controller parameters.

In this paper, a new adaptive fuzzy sliding mode controller is developed for a class of non-linear hysteretic systems. First, the problem is formulated where the hysteresis behavior is described by a backlash-like model. Then, a fuzzy system is used to approximate the unknown system dynamics and an adaptive sliding mode controller is constructed. Finally, an application example to show the performance of the proposed approach.

DC–DC converters process electrical energy by switching between a fixed number of configurations. The objective of controlling these systems is to provide better performances, ensure closed loop stability and guarantee a simple predictable behaviour. Based on a converter averaged model, we propose, in this paper, a systematic design approach of a fuzzy PID. The choice of controller parameters stands on the whole system stability requirements. Extension of the obtained asymptotic stability to structural stability is presented to show that the developed controller ensures also a simple and predictable behaviour of the converter. Finally, we illustrate the efficiency of the proposed fuzzy PID design approach through simulations in voltage mode as well as in current mode control.

The occurrence of nonlinear phenomena in DC-DC power converters makes their analysis and control difficult. We propose a converter model that takes into account the internal resistances of the converter elements. A fuzzy logic controller is then used to shift the nonlinear phenomena outside the operating domain, and to ensure current regulation over a wide range of parameters. To validate the achieved performance, a comparative study is presented.

The hysteresis non-linearity exists in many physical systems and materials, such as electrical and mechanical actuators, ferromagnetic and ferroelectric materials. However, this property makes the analysis and control of such systems and devices difficult. In order to control this property, a new Adaptive fuzzy synergetic control strategy is proposed in this paper. Indeed, to highlight the problem, the hysteresis behavior of the system is described using a backlash-like model. Then a synergetic control scheme is proposed to deal with the problem of controlling non-linear hysteretic systems. It's formed of a fuzzy system to approximate the unknown system dynamics with an adaptive synergetic controller to achieve the desired performances. The proposed approach is validated through simulation along with its satisfactory performances.

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Due to the special characteristics of piezoelectric actuators, the modelling and control task of these devices has been one of the most important research topic in the last decade. In the first part of this paper, a T-S fuzzy model is proposed to represent the behavior of this type of actuators and the recursive least squares (RLS) algorithm is used to optimize the parameters of this model. In the second part, based on an analytical model, a fuzzy PID controller for the piezoelectric actuator plant is presented. An ant colony optimization (ACO) algorithm is used to find the parameters of the proposed controller. The proposed approaches are validated through simulation along with their satisfactory performances.

This paper deals with the identification of the hysteresis property existing in piezoelectric actuators (PEA). In this paper, a fractional order model is used with the Recursive Least Squares (RLS) algorithm extended to fractional order models. The proposed approach is validated through numerical simulations and a comparison study is carried out to evaluate its performances.

This paper deals with piezoelectric actuators control. A fractional order fuzzy PID controller is designed for this class of systems with the help of particle swarm optimization (PSO) algorithm. The controller parameters are defined as an optimization problem and the PSO is used to find their optimal values. The proposed approach validation and their performances evaluation are done through simulation.

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Sliding mode control (SMC) is well known for its robustness and efficiency to deal with a wide range of control problems with nonlinear dynamics such as DC-DC power converters. In this paper, an optimized and fixed switching frequency sliding-mode policy for controlling DC-DC converters is proposed. There are two main contributions, in this paper; in the first we give a comprehensive proof of the SMC technique based on the converter functioning principle. In the second contribution, we provide a method of SMC parameters selection using simplex method. This allows obtaining the admissible ranges for SMC parameters while taking into account particle considerations about the converter. Then, theses ranges will be used as search space by the particle swarm optimization technique (PSO) to find the optimal controller parameters.

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This note comments some results in the paper “Design of practical sliding-mode controllers with constant switching frequency for power converters”, Int. J. Electric Power Syst. Res. 79 (2009) 796–802.

DC-DC converters are nonlinear systems that can exhibit complicated phenomena, which make difficult the system behaviour analysis and the controller design. The validity of any prediction and analysis of the converter behaviour are, mainly, related to the used modelling technique. For a rigorous description, an accurate modelling technique with minimum of simplifying assumptions is needed. In this study, a more general and simple modelling method of DC-DC converters is proposed. It is based on introducing enhancements to the existing discrete modelling approach of DC-DC power converters to obtain an accurate description of the system behaviour with a minimum of simplifying assumptions and validity hypothesis of the model. Copyright © 2010 John Wiley & Sons, Ltd.

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