Publications Internationales
Permanent URI for this collectionhttps://dspace.univ-boumerdes.dz/handle/123456789/13
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Item Voltage unbalance effects on induction motor performance(2006) Refoufi, Larbi; Bentarzi, Hamid; Dekhandji, Fatma ZohraThe reliability of electric drives and driven motors depends on the quality of the power supply voltage especially in the critical industrial process. In this work, a theoretical study of the effects of voltage unbalances, sags and swells on induction motor (IM) is performed by using the conventional method based on the theory of symmetrical components. For this study, MATLAB software program is developed for calculating currents, torque, power losses, temperature rises and derating factor. Besides, experiments have been carried out for obtaining currents, torque and power losses. An agreement that is found between the theoretical predictions and experimental data allows us to take into consideration the predicted derating factorItem Simulation of ion density distribution in the gate oxide of MOS structures(Modelling, Measurement and Control A, 2003) Bentarzi, Hamid; Bouderbala, R.; Zerguerras, A.In this work, the simulation of ions density distribution evolution within the oxide of MOS structures is performed. This simulation is achieved by solving the partial differential equation (PDE), which governs the motion of the ions in the oxide layer, subject to boundary and initial conditions. Since no closed form analytical solution is available in the literature to solve this important problem, a numerical technique based on Crank-Nicholson method is used. The evolution of ions density distribution is simulated for different values of such parameters as applied electric field and device temperature using BTS technique. The simulation results agree well with the experimental results as well as the previous published resultsItem Synthesis of linear arrays with sidelobe level reduction constraint using genetic algorithm(2008) Recioui, Abdelmadjid; Azrar, Arab; Bentarzi, Hamid; Dehmas, Mokrane; Chalal, MouloudThe synthesis of uniformly spaced linear array geometries with minimum sidelobe level and beamforming capability using genetic algorithms is presented. The iterative process aims not only at matching the desired pattern to the desired one but minimizing the sidelobe level as well; through optimizing the element excitations. Various examples are included to demonstrate the design effectiveness and flexibility namely for switched smart antenna systems applicationsItem Reliability assessment and improvement of medium power induction motor winding insulation protection system using predictive analysis(Springer, 2009) Chafai, M.; Refoufi, L.; Bentarzi, HamidThis chapter presents a reliability assessment of a widely used protection system of medium-power squirrel cage induction motors. In conjunction with published field induction motors reliability data, this assessment effort is based on a predictive analysis integrating three predictive techniques: (1) a fault tree analysis (FTA) that allows to identify and then quantify the initiating events weighting factors; (2) an event tree analysis (ETA) that allows to predict the protection system probability outcomes following an external disturbance; and (3) a failure mode effect and criticality analysis (FMECA) that will help set the stage to develop a preventive maintenance program fit to keep up the induction motor protection system reliability at the required level with particular attention given to aggressive environmental factors such as found in cement plantsItem Reliability assessment and improvement of large power induction motor winding insulation protection system using predictive analysis(2008) Chafai, Mahfoud; Refoufi, Larbi; Bentarzi, HamidThe paper presents a reliability assessment of a widely used protection system of large power squirrel cage induction motors. In conjunction with published field induction motors Failure data this assessment effort is based on a integrated predictive analysis using three methods: (1) a Fault Tree Analysis (FTA) that allows to identify and then quantify the initiating failure cause weighting factors; (2) an Event Tree Analysis (ETA) that allows to predict the protection system probability outcomes following an external disturbance and (3) a Failure Mode Effect and Criticality Analysis (FMECA) that will help set the stage for developing a preventive maintenance program fit to keep up the induction motor protection system reliability at the required level with particular attention given to aggressive environmental factors such as found in cement plantsItem Oxide charges densities determination using charge-pumping technique with BTS in MOS structures(2008) Bentarzi, Hamid; Zitouni, Abdelkader; Kribes, YoucefA New electrical method, using charge-pumping (CP) technique under bias thermal stress (BTS), has been described in this paper. This technique is based on the charge-pumping measurement which in turn used to extract the flat-band voltage before and after an applied bias voltage at high temperature. The obtained flat band voltage shift, that is due to redistribution of the mobile ionic charges, or to generation of the oxide trapped charge or both, may be used to determine their densitiesItem New approach of induction motor performance study under different voltage unbalance conditions(2006) Bentarzi, Hamid; Refoufi, L.; Dekhandji, Fatma ZohraItem A new approach applied to a thermal power plant controller using fuzzy logic(2009) Bentarzi, Hamid; Amr Chentir, Rabah; Belaidi, Nadir; Dif, Samah; E.Mastorakis, NikosThis work presents a new approach for controlling dynamic parameters of thermal power plant using Fuzzy logic. The control strategy is based on supervisor level using Fuzzy logic that is required to determine automatically the optimal process set points of regulations level. A thermal power plant simulator has been developed through the use of Matlab-Simulink. Besides, this paper describes hardware implementation using PLC based DCSItem Ionic current in MOS structures(2004) Bentarzi, Hamid; Bouderbala, Rachid; Zerguerras, AhmedA new approach of determining dynamic ionic current-voltage characteristic that is due to ion transport phenomenon in the oxide is presented. In this approach, the formulation of I–V characteristics ofmos device can be achieved through the use of the theoretical model of mobile ion distribution in oxides. The used theoretical model of ion distribution is based on the concept that the equilibrium concentration of the ions is obtained when the combined mobilizing forces, namely, thermal diffusion, internal, and external electric fields, become just sufficient to provide necessary activation energy to the ions to surmount the effective potential well. The obtained I–V curve is compared with the experimental curves under varying bias conditions by a slow linear ramp voltage at high temperature (tvs technique). An agreement between the experimental and computed curves provides a support to this method which in turn it gives formulation that is easier to apply for deriving the theoretical I–V characteristicItem Harmonic losses in inverter fed induction motor including skin effect(2005) Bentarzi, Hamid; Refoui, L.; Arras, A. H.