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The region of Adrar in Algeria is the windiest in the country; it is for this reason the electricity and gas company "Sonelgaz" has placed a wind farm of about 10 MW. Since it is a Saharan region, the wind is sandy, rich in silica that can damage the teeth of wind gearbox. The present work proposes a method which can make an early diagnosis of the broken tooth and its location in the gearbox, before the general breakdown. The modeling of defaults inside the turbine gearbox by symmetrical components technique is proposed successfully and for the first time in the field of diagnostics (usually this technique is used in the power grid lines short circuits analysis), associated with frequency response analysis. In addition, as it is impossible to install sensors at different parts, the increase in temperature and vibration inside the gearbox due to default, a sensor-less fault diagnosis based on the analysis of power signal generated by the wind turbine is presented and detailed. Furthermore, the peculiarity of this work is the modeling of unbalance forces caused by teeth failure on both the slow shaft and the fast shaft of the gearbox, which has never been considered before. It has been proven that this proposal allows a precise location of the broken tooth and the concerned gear inside the gearbox.

No abstract

Today, energy storage systems are strongly present both in industry and for individual applications, especially in on-board systems where an autonomous source of energy is required for power. Energy needs as well as the search for efficient means for its storage have become a very important research axis. Solar battery storage allows to store electricity generated from the sun via solar panels to ensure power supply in all circumstances (day or night, clear or overcast sky). This work focuses on modeling and dynamic simulation of a photovoltaic system with a Lithium Ion battery storage system (LI-BSS). Battery charge and discharge is performed using PWM current and voltage controllers using DC/DC bidirectional management converter BMC.

Wind energy generation has attracted great interests in recent years. Doubly-fed induction generator (DFIG) for wind turbines (WTs) are largely deployed, because variable-speed WTs have many advantages over fixed-speed generation such as increased energy capture, operation at maximum power point, improved efficiency and power quality. This paper presents the operation and vector control of a DFIG system, where the stator is connected directly to a stiff grid and the rotor is connected to the grid through bidirectional back-to-back AC–DC–AC converter. The basic operational characteristics, mathematical model of the aerodynamic system and vector control technique, which is used to obtain decoupled control of powers, are investigated using the software Matlab/Simulink.   Keywords: Wind turbine, doubly-fed induction generator, active and reactive power controller.