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1

Optimizing the operation of a photovoltaic generator by a genetically tuned fuzzy controller

Drir N, Barazane L., Loudini M.

Archives of Control Sciences

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2013

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Vol. 23, no. 2

145--167

EN

This paper presents design and application of advanced control scheme which integrates fuzzy logic concepts and genetic algorithms to track the maximum power point in photovoltaic system. The parameters of adopted fuzzy logic controller are optimized using genetic algorithm with innovative tuning procedures. The synthesized genetic algorithm which optimizes fuzzy logic controller is implemented and tested to achieve a precise control of the maximum power point response of the photovoltaic generator. The performance of the adopted control strategy is examined through a series of simulation experiments which prove good tracking properties and fast response to changes of different meteorological conditions such as isolation or temperature.

2

Contribution to variable structure control based on the approach of fuzzy modeling of Ben-Ghalia for induction motor with Luenberger observer

Barazane L., Khwaldeh A., Krishan M. M., Sicard P.

Archives of Control Sciences

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2008

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Vol. 18, no. 4

453-476

EN

Sliding mode and fuzzy logic control have been combined together in a variety of ways. In this paper, a novel direction to design fuzzy sliding controllers is proposed based on the approach of Ben-Ghalia et al. Which is able to provide a fuzzy set based on a decoupled and linear system obtained after the application of the feedback- linearization control to the model of an induction motor. On the other hand, a Luenberger observer is conceived in the present work to observe the rotor flux in the motor which is too important to permit the application of fuzzy modeling approach and ensure the optimal and required performances . Furthermore, another objective to use such an observer consists in stabilizing the system and rejecting the disturbances when the system is subjected to uncertainties. Furthermore, to overcome the problem of the chattering phenomenon generated by the application of conventional sliding mode control applied to the cascade structure of the motor, the approach of fuzzy sliding mode control based on the fuzzy modelling proposed by Ben-Ghalia is used. The robust fuzzy control design is made feasible without resorting to model simplification or imposing restrictive conditions on the system uncertainty. Finally, simulation results proves the capability of the proposed process to ensure a good performances and robustness which is the principal aim of this research

3

New approach to linguistic fuzzy modeling of induction motor fed by PWM voltage source inverter

Barazane L., Krishan M. M., Khwaldeh A., Sicard P.

Archives of Control Sciences

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2007

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Vol. 17, no. 2

209-235

EN

In this paper, a new approach of linguistic fuzzy modeling proposed by Ben-Ghalia et al. is applied to induction motor. Thus, a classical model is first given together with the most used asynchronous motor control strategy, which is the pole assignment. After more, in order to minimize the dependence of the system to parameter variations and external perturbations, and reduce the number of variable states, a new model of the original system is proposed. This model is too simple and is suitable to cognitive approach such as fuzzy modeling. Then, fuzzy modeling of an uncertain system using the approach of Ben-Ghalia et al. to reduce the effects of imperfections of the classical modeling are introduced. In addition, their applications in the fuzzy sliding mode control of the asynchronous motor are presented. Finally, Simulation results reveal some very interesting features and show that the proposed fuzzy model has great potential for use as an alternative to the approximation of the conventional model of induction motor taking into account the effect of system model uncertainties and gives a good performances in sliding mode control.

4

Robust hybrid control based on feedback linearization and field-oriented controls of induction motor

Barazane L., Larbes C., Boucherit M.S., Ouiguini R.

Archives of Electrical Engineering

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2003

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Vol. 52, nr 2

115--135

EN

During the last decades pulse width modulation (PWM) voltage source inverter fed induction motor based drives have improved in many aspects and arc becoming a real alternative to DC drives. In order to obtain high performance speed response, field oriented control techniques are usually used to control the torque and the flux separately as in DC motors. However, it is well known that these methods suffer from the sensitivity to parameter variations and from the coupling problem between the torque and the flux variables when the flux changes. To try to solve the above problems an approach to the field oriented control is presented in this paper. It is based on the association of the feedback linearization control (FLC) with the field-oriented control (FOC) resulting in a hybrid system. The FLC is applied in the rotating field reference frame and with an adequate choice of the output variables a total linearization is obtained and the decoupling is maintained for the whole range of the rotating speed whatever the operating modes. Sliding mode regulators are used here to solve the problem of sensitivity to parameter variations and to external disturbances. A new smooth piecewise function is given to reduce the problem of chattering, which is inherent in sliding mode controllers. Furthermore, since the rotor fluxes components are not usually measurable, a closed-loop observer is derived to estimate these latters and the speed of the motor. The paper describes the different steps of the design of this control technique and gives both the theoretical analyses as well as the simulation results. These latters revealed very interesting features and showed that this method can be an alternative to the conventional FOC.

PL

W ostatnich dziesięcioleciach napędy z silnikami indukcyjnymi zasilanymi z inwertorów napięciowych z modulacją szerokości impulsów PWM zostały bardzo udoskonalone i stały się konkurencyjne do napędów z silnikami prądu stałego. Dla uzyskania dokładnej regulacji prędkości wykorzystuje się zazwyczaj sterowanie polowo zorientowane w celu niezależnej regulacji momentu i strumienia, jak w silnikach prądu stałego. Wiadomo jednak, że takie sterowanie jest czułe na zmiany parametrów i że zmiany strumienia pociągają za sobą zmiany momentu. Dla rozwiązania tego problemu w artykule zaprezentowano nowe podejście do sterowania polowo zorientowanego. Polega ono na połączeniu sterowania ze zlinearyzowanym sprzężeniem zwrotnym (FLC -feedback linearization control) ze sterowaniem polowo zorientowanym (FOC-field-oriented control) w system hybrydowy. FLC jest zastosowane w odniesieniu do pola wirującego i przy odpowiednim doborze zmiennych wyjściowych uzyskuje się całkowitą linearyzację i odsprzężenie momentu i strumienia w całym zakresie prędkości obrotowej dla dowolnego rodzaju pracy. Dla rozwiązania problemu czułości napędu na zmiany wartości parametrów i na zakłócenia zewnętrzne wykorzystano regulatory do sterowania z ruchem ślizgowym. Wprowadzono nową gładką funkcję odcinkową dla zredukowania pulsacji towarzyszących zastosowaniu takich regulatorów. Ponadto, ponieważ w praktyce składowe strumienia rotora nie są przeważnie mierzalne, wprowadzono obwody estymatorów pozwalających na określenie tych wartości i wartości prędkości obrotowej. Artykuł opisuje poszczególne stopnie projektowania tej techniki sterowania i przedstawia wyniki analizy teoretycznej i badań symulacyjnych. Badania te uwidaczniają bardzo interesujące właściwości metody i wskazują, że może być ona zastosowana zamiast konwencjonalnej POC.