The International Journal of Energetica

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4E (Energy-Exergy-Economic-Environmental) performances assessment of different configurations of power cycles
(جامعة الوادي - university of el oued, 2021-10-30) Meriche, slem; Chemoul, Adem; Boukelia, Taqiy Eddine
Steam power plants are alimented by different sources of energy including fossil fuels or renewable ones such as solar thermal, biomass or geothermal. Thus, thermodynamic, economic and environmental analyses of different steam power cycles are highly required for identification and choice of the most effective and viable layout to be adopted in the installation. Consequently, the main aim of the present paper is to compare five different configurations of power cycles in terms of energy and exergy efficiencies, fuel and cooling water consumptions, CO2 emissions rate, as well as investment and operating costs, and net present value (NPV). The obtained results present relevant differences; the energy and exergy efficiencies of the fifth configuration similar to the one of Achouat power station are the highest with 41.9% and 39.5% respectively. On the other hand, this configuration shows better environmental performances represented by CO2 emission (46.12 kg/s), and water consumption for cooling (7.42 m3/s). Economically, there is a clear convergence in the NPV values for configurations with Reheating and Regeneration processes. Moreover, the fourth configuration is the best in terms of net present value (NPV) of 103.1(M€).
Abdelkader Bellila. Evaluating the Impact of Absorber Geometry on Solar Still Efficiency: A Comparative Study of Square and Round Absorbers
(University of Eloued جامعة الوادي, 2024-05-08) Ayoub Barkat- Zakaria Rahal-Karim Medjdoub- Aazar M.A. Daoud- Tamás Mester-Hamza Chekima
Solar stills have been used for many years in areas with limited access to fresh water, such as desert regions or remote locations. They are simple to construct using readily available materials and require no energy input other than sunlight. Additionally, solar stills are lowmaintenance and can produce a significant amount of pure water with relatively little effort. Two solar stills are exposed to the sun, the first is a single solar still and the other is a hemispherical sender. Both stills have similar absorber. The purpose of this experiment is to compare the pure water output of the two devices. The finding shows that hemispherical solar still is more efficient than the simple solar still by 54.30 % in terms of pure water output. This suggests that the hemispherical still is better at capturing and utilizing solar energy to evaporate and condense water.
Analysis for inter turn stator fault with load variation in Induction Motor
(جامعة الوادي Université ofEl-Oued, 2023-06-15) Cherif, Hakima; Maamir, Madiha; Chehaidia, Seif Eddine
This paper investigates the impact of load variation on the diagnosis of inter-turn stator faults in induction machines. The proposed detection technique relies on the analysis of stator current using the discrete wavelet transform (DWT) in both normal and faulty states of the machine. The energy of the approximation and detail signals obtained from DWT provides valuable information about the machine's health and the severity of the inter-turn stator faults. Experimental tests were conducted using a dSpace 1104 signal card-based interface to study the load effects in detecting and diagnosing stator inter-turn short circuit faults in induction motor
ANFIS Models for Fault Detection and Isolation in the Drive Train of a Wind Turbine
(جامعة الوادي - university of el oued, 2022-12-25) Zemal, Zakariai; Cherroun, Lakhmissi; Hadroug, Hafaifa
The paper aims to improve the fault detection and isolation process in wind turbine systems by developing intelligent systems that can effectively identify and isolate faults. Specifically, the paper focuses on the drive train part of a horizontal axis wind turbine machine. The proposed fault diagnostic strategy is designed using an adaptive neural fuzzy inference system (ANFIS), which is a type of artificial neural network that combines the advantages of both fuzzy logic and neural networks. The ANFIS is used to generate residuals that occur after faults have been detected, and to determine the appropriate thresholds needed to correctly detect faults. The simulation results show that the proposed fault diagnostic strategy is effective in detecting faults in the drive train part of the wind turbine system. By using intelligent systems such as ANFIS, the fault detection process can be automated and streamlined, potentially reducing maintenance costs and improving the overall performance and efficiency of wind turbine systems.
Antonio Marcos de Oliveira Siqueira. Julio Cesar Costa Campos. Messoudi, Mohammed Meftah . Rafael Azevedo Santos.Design, Implementation, and Analysis of a Local Pelton Turbine.
(University of Eloued جامعة الوادي, 2024-04-15) Khechekhouche , Abderrahmane
This study investigates the performance characteristics of a locally designed Pelton turbine, focusing on the relationship between rotational speed, torque, and mechanical power output. Understanding these dynamics is crucial for optimizing turbine efficiency in various applications. Our experiments revealed that as the turbine’s rotational speed increased to 844 RPM, the torque decreased from 0.090 to 0.079 N·m, indicating a reduction in the efficiency of energy transfer from the water jets to the turbine buckets from 39% to 33%. This decline highlights the importance of maintaining an optimal speed range to maximize energy conversion. Furthermore, while power output initially increases with speed, operating the turbine beyond its optimal range can lead to diminishing returns due to mechanical and efficiency losses. These findings provide valuable insights for improving the design and operational strategies of Pelton turbines, ensuring enhanced performance and reliability
Application of Grey Wolf Optimization Algorithm for Maximum Power Point Tracking of Solar Panels
(University of Eloued جامعة الوادي, 2024-04-08) Khelaifa , Fethi .Lamamra, Kheireddine . Toumi , Djaafar
One of the applications of evolutionary algorithms is increasing the efficiency of photovoltaic (PV) systems. The main problem with using standard algorithms like the Incremental Conductance (IC) controller for maximum power point tracking (MPPT) under partial shading conditions (PSC) is that they do not provide reliable tracking of the global peak of the volt-watt characteristic, leading to increased losses and reduced power plant performance. Furthermore, there is currently no methodology for selecting the optimal sampling time of soft computing algorithm-based maximum power trackers for PV systems. The aim of this paper is to apply the Grey Wolf technique with optimally selected sampling time, which will result in fast and reliable tracking of the global maximum point of the PV panels. The results show that the selected optimal sampling time for the digital MPP controllers can increase the performance and efficiency of MPPT controllers. A DC-DC boost converter is used to match the PV panels with the resistive load. Several simulations were performed using MATLAB/Simulink to examine the performance of the proposed system. The results demonstrate that the proposed Grey Wolf algorithm can quickly capture the GMPP within 0.2 seconds under different shading conditions of the PV panels.
Bioclimatic approach of passive cooling techniques for the design of buildings in southern Algeria
(جامعة الوادي - university of el oued, 2021-06-03) Hebbal, Belkhir; Yacine, Marif; Kaddour, Abdelmadjid; Belhadj, Mustapha
The bioclimatic approach looks into the opportunities for building conception under the local climatic conditions. The first bioclimatic chart has been developed by Olgyay which combines temperature with relative humidity to characterize the comfort zone. It is founded on outside climate conditions to identify attenuation measures such as solar radiation, wind speed, or shading to reach comfortable inside conditions. Givoni created also a bioclimatic chart founded on inside conditions using the physical and thermal properties of air. Bioclimatic approach strategies contribute to decreasing the building energy loads and increasing thermal comfort for its residents over the year. The principal aim of this research is to evaluate a bioclimatic approach to passive cooling for building design in Algeria's South using Givoni's Bioclimatic chart and Olgyay's Bioclimatic chart. Climate data of various locations (Ouargla, Ghardaia, and El Oued) within this area were collected and analyzed. Furthermore, an overview of appropriated conception strategies for the hot season for each zone is developed. The results show that the maximum average temperature from June to August at around 43.1°C. After applying passive cooling strategies, the temperature indoor can be decreased from about 26.1 to 31.4°C, which can be described as being in the comfort zone for the three studied locations. Finally, these findings can contribute to understanding the thermal behavior of residential buildings and offer guidelines to develop a convenient concept of what the building composition should look like in arid and hot climates.
Cellulose cardboard effect on the performance of a conventional solar still
(جامعة الوادي Université ofEl-Oued, 2023-05-12) Bellila, Abderlkader; Rahal, Zakaria; nichenko, anichenko; Sadoun, Ali
The lack of drinking water is a pressing issue in contemporary times, and solar distillation stands out as a simple and effective solution. However, the low yield of solar distillation remains a challenge. Researchers have undertaken various experimental modifications to enhance the thermal performance of solar distillation. In one such modification, Cellulose cardboard was introduced with the aim of improving the system's performance. The experimental results demonstrated a notable improvement of 19.8% in the solar still's efficiency when Cellulose cardboard was employed, compared to conventional solar still designs.
CFD simulation of natural convection and heat transfer in a flat solar thermal collector with fins on the glazing - horizontal case
(جامعة الوادي - university of el oued, 2018-12-06) Laaraba, Adel
This study is based on a CFD simulation of a flat horizontal solar thermal collector containing fins on its inner face of the glazing. The walls of the solar collector with insulation are considered adiabatic and the rest of the walls are at constant different temperatures. The principal objective of this work is to study the effects of the number of fins that changed from 0 to 30, as well as their length varied from 0 to 0.8 on the air flow and heat transfer characteristics. It has been observed that the heat transfer rate is strongly affected by the number of fins and the length of the fins. The obtained result showed that the increase of the fins reduces the heat loss by convection by 54 %.
Comparative Study Between Fuzzy and Sliding Mode Control Based on a BDFIG
(جامعة الوادي - university of el oued, 2019-12-15) Ouada, Laid; Sebti, B
Brushless doubly fed induction (BDFIG) is one of the best solutions of the previous research efforts about wind-power converter, which is represented by the absence of a brush gear and less maintenance cost, especially in the harsh regions. This task presents a comparative evaluation between a sliding mode and Fuzzy control. It demonstrates also the robustness of these two regulators against supply voltage and load disturbances. Furthermore, we have shown the undesirable phenomenon of oscillations having a finite frequency and amplitude, which is known as ‘chattering’ resulted from a sliding mode control which is based on Lyapunov approach theorem. The control of the system and BDFIG are both integrated in variable speed wind energy conversion. The performances of these control systems have been tested and analyzed in Matlab Simulink
Comparative study between pi and fuzzy pi controllers for DFIG integrated in variable speed wind turbine
(جامعة الوادي - university of el oued, 2019-12-15) Mesai, H; Bentaallah, A; Djeriri, Y; Mahmoudi, A
This paper presents the contribution of the application of fuzzy logic for the independent control of the active and reactive power stator of a doubly fed induction generator (DFIG), used in a variable speed wind energy conversion system. So in this work, we are particularly interested in the application of indirect vector control by stator flux orientation to the DFIG, based on fuzzy controllers. These latter surpass the limits of conventional controllers and possess essential characteristics for the improvement of the robustness of the vector control with against parameters variations of the system. The obtained simulation results have shown that it is possible to control the stator powers, even in the presence of parametric variations
Comparative Study between Sliding Mode Control and the Vectorial Control of a Brushless doubly fed induction generator
(جامعة الوادي - university of el oued, 2018-12-17) Oussama, Moussa; Rachid, Abdessemed; Said, Benaggoune; Benguesmia, Hani
Brushless doubly fed induction generators (BDFIG) show commercial promise for wind-power generation due to their lower capital and operational costs and higher reliability as compared with doubly fed induction generators. This paper proposes a robust sliding mode control of grid-connected brushless doubly fed induction generator (BDFIG). The developed algorithm is based on the decoupling control by using oriented grid flux vector control strategy. The decoupling of the active and the reactive stator powers insures an optimal performance of the BDFIG at the sub-synchronous region. The stator of this machine incorporates two sets of three phase windings with different number of poles, power winding (PW) and control winding (CW). The proposed method is tested with the Matlab/Simulink software. Simulation results illustrate the performances and the feasibility of the designed control
Continuous Nonlinear Model Predictive Current Control of PWM AC/DC Rectifier
(جامعة الوادي - university of el oued, 2021-12-22) Merzouk, Imad; Bessous, Noureddine; Rezaoui, ,Mohamed Mounir
The present work applies a nonlinear model predictive current control (NLMPCC) approach to ac/dc pulse width modulation (PWM) rectifier. A cascade structure is used to regulate Dc-link voltage and grid currents. The outer loop objective is to regulate the Dc-link voltage to the desired value, providing the level of the required active power to be used with the reactive power to calculate the referencing current for the inner loop. In the inner loop, the proposed approach is considered. After that, the nonlinear model of the converter is developed, based on continuous minimization of predicted tracking errors, the voltage at the terminal of the converter is deduced. After that, a PWM block is used to generate gate signals. Simulation results are performed to illustrate the efficiency of the proposed control law
Control of 3x7 matrix converter with PWM three intervals modulation
(جامعة الوادي - university of el oued, 2019-12-15) Mesai, H; Bentaallah, A; Djeriri, Y; Mahmoudi, A
Direct Power conversion from fixed AC voltage into variable AC voltage is gaining a significant attention, especially in case of multi-phases machines/generators; for such reason a new algorithm to control 3x7 matrix converter (MC) is developed in this paper, wherein the main aim is to control multi-phases induction motor/generator connected to the electrical grid with a novel converter (except matrix converter), for that the PWM three intervals modulation strategy is modified from the control of 3x3 MC to 3x7 MC; which is directly connected to the network through a three phase input in order to overcome the supplying problems, on the other side seven phases have been used as an output to benefit the advantages of the multi-phases machines. This paper intends in the first place to explain the 3x3 MC, then to manipulate the control equation for the purpose of making it suitable for controlling the 3x7 MC effectively, thus a good performance can be clearly seen according to the quality of the output voltage/current under typical R-L load, the shift between phases and the THD evaluation. The obtained simulation results which demonstrate the efficiency of the new control algorithm are presented and discussed
Control with Sliding Mode of a Five-Phase Series-Connected Two-asynchronous Motor Drive
(جامعة الوادي - university of el oued, 2018-06-28) zouaid, zouaid; i nezli, Lazhari
In this paper, we study sliding mode control of series-connected five-phase two asynchronous machines supplied with a three levels inverter. After presentation of multiphase machines, we worked out the mathematical model of five phase asynchronous machine supplied with voltage inverter. Application of Park transformation reduces considerably the mathematical model of machine. After, we applied vector control and sliding mode control to the five-phase induction machine. After that, we study a multi-machine system, which comport five-phase two asynchronous machines supplied with a single voltage inverter. In the last, we had the sliding mode control of series-connected five-phase two asynchronous machines. Simulations are presented to show the effectiveness of the control strategy. We observe that an appropriate transposition of phase’s order permits an independent control of two machines.
Cooling Effect on a solar still condenser
(University of Eloued جامعة الوادي, 2023-11-20) Smakdji , N. Khelassi-Sefaoui,A.Bourdim,M.Siqueira,A
This research delves into the quantitative impact of design modifications on solar still performance, specifically examining the role of fins on the glass cover. Comparative analyses were conducted on two solar stills, SSref (Solar Still reference) and SSmod (Solar Still modified with fins), considering temperature variation, energy transfer, energy evaporation, hourly water output, and internal efficiency. SSmod consistently exhibited superior performance, maintaining lower temperatures (peak difference of 10 °C), achieving an average energy transfer of 555 W/m², a higher energy evaporation rate (335 W/m² on average), and an increased hourly water output (0.59 mL peak). The internal efficiency for SSmod averaged 0.741%, surpassing SSref's 0.713%. These quantified results highlight the crucial contribution of fins in enhancing distillation processes, providing a valuable foundation for designing solar stills with improved energy efficiency and resource utilization
Cooling Effect on a solar still condenser
(University of Eloued جامعة الوادي, 2024-11-20) Smakdji , N. Khelassi-Sefaoui,A.Bourdim,M.Siqueira,A
A data logging system has been deployed to monitor two solar panels positioned at distinct inclination angles. This system records crucial parameters such as current, voltage, solar radiation incident on the panels, and panel temperatures. Comprising an Arduino microcontroller, a current sensor, a current and voltage sensor, and a Memory Card, the data logger captures and stores data in .txt files at 20-minute intervals. Employing a real-time acquisition system, the obtained results indicate that the data logger effectively archives and presents a wealth of information about solar panel characteristics. Notably, the data reveals superior performance of the solar panels at a 35-degree tilt angle compared to 32 degrees during April in the Ouargla region of Algeria
Design and Economic Evaluation of a Photovoltaic Water Pumping System for Tomato Irrigation in El Oued
(University of Eloued جامعة الوادي, 2024-05-18) Rehouma , Youssef . Yasmine , Amara.Danoune , Mohamed Bilal . Gougui Abdelmoumen. Naoui,Mohamed
This paper explores the design, economic assessment, and operation of a photovoltaic water pumping system for irrigating tomatoes in Terifaoui, El Oued, Algeria. Terifaoui's desert climate and lack of grid access make it a suitable candidate for a solar-powered irrigation system. The system design, simulated using PVsyst software, considers El Oued's climate to ensure reliable operation. This study examines the technology, economics, and operational aspects of the system, highlighting its potential to boost agricultural output and regional economic resilience
Detection and Diagnosis faults in Machine asynchronous based on single processing
(جامعة الوادي - university of el oued, 2019-04-20) Chouidira, Ibrahim; Khodjae, Djalal Eddine; Benguesmia, Hani
In this work, we proposed multi-winding model for the simulation of broken bars in squirrel cage asynchronous machine, this model allows to study the influence of the broken bar defects on the behavior general of machines in different operating conditions (healthy and faulty). The breaking of the most frequent bars of the rotor causes oscillations of the torque, speed, and the current, the increase of the resistance of the rotor creates the defects proportional with the number of breaks bar K .The diagnosis fault using technique of single processing based on Spectrum analysis for detection broken bar. The results of the simulation obtained allowed us to show the importance of this technique for detection broken bar
Developed nonlinear model based on bootstrap aggregated neural networks for predicting global hourly scale horizontal irradiance
(جامعة الوادي Université ofEl-Oued, 2023-05-06) Dahmani, Abdennasser; Ammi, Yamina; Hanini, Salah; Driss, Zied
This research study examines the use of two models of artificial intelligence based on a single neural network (SNN) and bootstrap aggregated neural networks (BANN) for the prediction value of hourly global horizontal irradiance (GHI) received over one year in Tamanrasset City (Southern Algeria). The SNN and BANN were created using overall data points. To improve the accuracy and durability of neural network models generated with a limited amount of training data, stacked neural networks are developed. To create many subsets of training data, the training dataset is re-sampled using bootstrap re-sampling with replacement. A neural network model is created for each set of training datasets. A stacked neural network is created by combining multiple individual neural networks (INN). For the testing phase, higher correlation coefficients (R = 0.9580) were discovered when experimental global horizontal irradiance (GHI) was compared to predicted global horizontal irradiance (GHI). The performance of the models (INN, BANN, and SNN) demonstrates that models generated with BANN are more accurate and robust than models built with individual neural networks (INN) and (SNN).

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