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wind energy features prominently as a supplementary energy booster. It does not pollute and is inexhaustible. However, its high cost is a major constraint, especially on the less windy sites. The purpose of wind energy systems is to maximize energy efficiency, and extract maximum power from the wind speed. In This case, the MPPT control becomes important. To realize this control, strategy conventional Proportional and Integral (PI) controller is usually used. However, this strategy cannot achieve better performance. This paper proposes other control methods of a turbine which optimizes its production such as fuzzy logic, sliding mode control. These methods improve the quality and energy efficiency. The proposed Sliding Mode Control (SMC) strategy and the fuzzy controllers have presented attractive features such as robustness to parametric uncertainties of the turbine, simplicity of its design and good performances. The simulation result under Matlab\Simulink has validated the performance of the proposed MPPT strategies.

This work proposes a robust control scheme of a three-phase induction motor using a new Backstepping approach based on variable gains. Because of the saturation blocks that are essential to protect the control system, the use of conventional integral Backstepping could lead to a modest performance represented by overshooting and strong vibrations in transitional regimes that cause overcurrent. To develop an efficient and simple control algorithm, the variable gains propriety is used in the speed controller to offer a quick response without overshooting with good robustness against external disturbances. The same property has been introduced in current regulation by a different mean in order to develop a new solution to solve obstacles related to very low-speed operations. The asymptotic stability of the global control is proven by Lyapunov theory. The improvement of the new version compared with the classical one was verified by a brief comparative study based on simulation results. The proposed algorithm has been implemented in a dSPACE DS 1104 card, to analyze the real-time motor performance, and to test control sensitivity against parametric variations. The obtained results show a remarkable improvement of the new control concerning rapidity and stability of transient regimes, overtaking elimination and reduction of starting current, with a low algorithm sensitivity against parametric variations. We have also been able to confirm that the new current control method can guarantee optimal regulation in order to achieve a high-performance operation at very low-speed zones, in the presence of various internal and external disturbances. [ABSTRACT FROM AUTHOR]

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Electric motors play a very important role for safe and efficient running of any industrial or power plant. Early detection of abnormalities in the motor will help and avoid expensive failures. Bearing faults create asymmetries and result in abnormal amplitude of the harmonics around the fundamental supply frequency and its harmonics. It has been shown that bearing faults can be detected by several methods. Frequency estimation techniques have been developed and used to detect bearing faults. In this paper an overview of the Concordia vectors technique (namely the a and β components) is applied to the detection of bearing faults. Our main objective is to investigate which of the two components is most sensitive to bearing faults. Experimental tests performed on a number of faulty bearings show that the β-quadrature component is more sensitive to these types of faults. [ABSTRACT FROM AUTHOR]

Permanent magnet synchronous machine (Shortened later on PMSM) has shown increasing popularity in recent years for industrial drive application due to the recent development in magnetic materials, power converters, and digital signal processors. In particular, PMSM drives are widely used in high performance drive (HPD) applications. Fast and accurate speed response and quick recovery of speed from any disturbances are essential. The control of a high performance permanent magnet synchronous motor drive for general industrial application has received wide spread interest for researchers. In this work, a novel speed and position control scheme for a (PMSM) is developed based on a nonlinear adaptive control scheme. The vector control scheme is used to simplify control of the PMSM. System model equations are represented in the synchronously rotating reference frame and provide the basis for the controller which is designed using the adaptive backstepping nonlinear (Shortened later on ABNL) technique. Using Lyapunov's stability theory, it is also shown that the control variables are asymptotically stable. The complete system model is developed and then simulated using MATLAB/Simulink software. Performance of the proposed controller is investigated extensively at different dynamic operating conditions such as sudden load change, command speed change, command position change and parameter variation. The results show the global stability of the proposed controller and hence found to be suitable for high performance industrial drive applications. The real time implementation of the complete drive system is currently underway. [ABSTRACT FROM AUTHOR]

The article presents the optimization of shunt active power filter parameters based on fuzzy logic control. The constant or fuzzy hysteresis-band techniques, which are employed to derive the switching signals is the basis of the current active filter controller. The energy storage of the de capacitor is optimized by the direct current voltage controller and the proportional-integral and fuzzy logic controllers are developed and compared.