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This paper presents the doubly fed induction motor (DFIM) speed control using adaptive fuzzy logic PI (AFLPI) controller to give better dynamic performances. Before the advent of modern technology, integral proportional based current controller is usually used due to its simplicity. But, the effectiveness of closed-loop control is widely affected by applied this type of controls, taking into account that the PI controllers have tuning problems. To overcome the problem, a new technique AFLPI based speed controller for direct field oriented control fed DFIM to get fast speed response and to minimize the torque ripple. The application of this type of control is very satisfactory to replace the conventional PI controller and, even the fuzzy logic PI (FLPI) controller. The performances of DFIM driving under the field-oriented application are simulated under different operating conditions using the AFLPI controller. The simulation results obtained with AFLPI are compared with those obtained in the case of the FLPI controller and the conventional PI controller. Accordingly, an improvement in dynamic and robustness is clearly appears in AFLPI controller simulation results compared to the others aforementioned controllers. Simulation Results are presented for the three techniques using Matlab/Simulink to prove the dynamic performances and robustness.

In this article, we present the construction of observers of rotor flux and mechanical speed needed for robust control of the induction machine. Two observers will be developed for comparison. The first is based on the techniques MRAS and the second is observer of KUBOTA, with the enhanced DTC-ANN (by artificial intelligence), "sensorless DTC-ANN". The validity of the proposed methods is confirmed by the simulation results. Through this comparative study we examine each observer in terms of characteristics that distinguish him from the other through these estimated value and error of estimation (flux and the speed of rotation) on the one hand, and on the other hand we study a property of great importance in the control and the response and robustness of the observer for very low speeds. In my work I concentrate this on the observer of KUBOTA because I noticed that during my research in the previous research and research there is very little and no detail even in terms of mathematical model in addition to the form of comparative study between him and the observer of MRAS in terms of the principle of control, accuracy, sensitivity and special response to low speeds and error In observation.The THD (Total Harmonic Distortion) of stator current, torque ripple and stator flux ripple are determined and compared with conventional DTC control scheme using Matlab/Simulink environment.

This project presents a strategy of field control then sliding mode control put in to the conversion process of wind energy containing an asynchronous generator with double fed (DFAG; DFIG). A model was developed for each component of the wind turbine (turbine, DFAG and cascade rectifier-inverter). MPPT device must be introduced in order to obtain maximum energy efficiency so that PI-MPPT method is made. The objective is to apply this command to control independently the active and reactive powers generated by the asynchronous generator uncoupled by orientation from the flow. The results of digital simulations obtained show the improvement of the performances of the sliding control compared to the field control, also it has provided information on the commands available techniques as reference tracking and robustness.

In this paper, DTC is applied for two-level inverter fed IM drives based on neuronal hysteresis comparators and The Direct Torque Control (DTC) is known to produce quick and robust response in AC drive system. However, during steady state, torque, flux and current ripple. An improvement of electric drive system can be obtained using a DTC method based on ANNs which reduces the torque and flux ripples, the estimated the rotor speed using the KUBOTA observer method based on measurements of electrical quantities of the motor. The validity of the proposed methods is confirmed by the simulation results.The THD (Total Harmonic Distortion) of stator current, torque ripple and stator flux ripple are determined and compared with conventional DTC control scheme using Matlab/Simulink environment.

In this paper, a comparison is carried out between MPPT technique using a hybrid cascaded Fuzzy-PI Controller and Perturb and Observe (P&O) MPPT technique. The two techniques are compared in a system which consists of a photovoltaic system connected to a grid via a two-level three-phase inverter. The P&O and Fuzzy-PI techniques are examined under different weather conditions, namely, ramp change in irradiation level and ramp change in temperature levels. Disturbances represented by fluctuations in power demand from the utility grid is generated to assess the robustness of each of the two controllers. The Fuzzy-PI based MPPT, has proved its excellent tracking and robustness against abrupt perturbations. Simulations of the system performances using the two regulators are performed to validate the conceptual standings.

Three-phase static converters with voltage structure are widely used in many industrial systems. In order to prevent the propagation of the fault to other components of the system and ensure continuity of service in the event of a failure of the converter, efficient and fast methods of detection and localization must be implemented. This paper work addresses a diagnostic technique based on the discrete wavelet transforms (DWT) for the detection of an inverter IGBT open-circuit switch fault. The study focuses on the investigation of the harmonics (related to the obtained details) which may appear in the spectrum due to the faults. To illustrate the merits of the technique and validate the results, experimental tests are conducted using a built voltage inverter fed induction motor. The inverter is controlled by the SVM control strategy.

This paper work addresses the enhancement of this technique by associating it the polar coordinates as a proposed tool for a better detection and location of the faulty inverter switch. The proposed use of the polar coordinates tool not only allows the exact computation of both the magnitude and the phase angle values of the fault current vector allied to the faulty inverter IGBT but also enables to develop a simple graphical representation to facilitate the detection and location of the inverter fault by using a fault current vector representation instead of a trajectory representation as that in Park's vectors technique. To illustrate the merits and effectiveness of the enhanced detection Park's current technique, several simulation results are obtained and then validated by employing the experimental test-rig realized by the ‘diagnostic group’ in our LDEE laboratory.

This paper addresses a thorough investigation study of the various possible faults that are related to a three phase two-level inverter fed induction motor. The treated faults are concerned with the inverter internal faults, the DC-link fault and one isolated phase of the inverter. The consequences of the mentioned failure modes are analyzed. A study of the impact of each fault on the induction motor behavior is being investigated. The work is carried out using an inverter fed induction motor with an SVM-Back stepping control technique. A detection technique based on the stator current spectrum analysis is also proposed to detect and locate both the open-circuit switch and short-circuit switch faults that may occur in the inverter. The obtained results illustrate well the effectiveness of the detection technique as well as the various degraded operations of the motor due to the different faults associated with the inverter.

This work falls within the scope of detection and localization of defects in electrical drives and in particular those based on asynchronous machines. The choice of the machine is justified by the growing success that it has generated, in particular, in variable speed electric drives.Asynchronous machine-based electrical drives are widely used in industrial applications because of their low cost, performance and robustness.Our contribution focuses on the monitoring and diagnosis of defects in the asynchronous machine such as bearing defects, rotor bar failure defects and bearing defects. In this context, we proposed two approaches for fault detection by monitoring the stator current, in this case the signal approach and the system approach.The signal approach is based on the processing and analysis of the temporal or frequency signal of the stator current.The model approach, which relies on the extended state observers. Extended filters based on linear models are applied for diagnosis, Ce travail s’inscrit dans la thématique de la détection et localisation de défauts dans les entraînements électriques et en particulier ceux à base de machine asynchrone. Le choix de la machine est justifié par le succès grandissant qu’elle a suscité, notamment, dans les entraînements électriques à vitesse variable.Les entraînements électriques à base de machine asynchrone sont largement utilisés dans les applications industrielles en raison de leurs faibles couts, de leurs performances et de leurs robustesses.Notre contribution s’intéresse à la surveillance et au diagnostic des défauts dans la machine asynchrone tels que les défauts de roulements, les défauts de rupture de barres rotoriques et les défauts de roulements. Dans ce contexte, nous avons proposé deux approches de détection de défaut par la surveillance du courant statorique en l’occurrence l’approche signal et l’approche système.L’approche signal, elle se base sur le traitement et l’analyse du signal temporel ou fréquentiel du courant statorique.L’approche modèle, qui repose sur les l’observateurs d’état étendu. Des filtres étendus à base de modèle linéaires sont appliqués pour le diagnostic