Mediterranean Journal of Modeling and Simulation

9

Authors: M. N. Benallal, A. C. Vataev, A. Doane, K. Hamouda, T. Nahdi

This article describes the results of experimental studies of HF input and primary parameters. A simulation model in Matlab SimulinkTM of multiphase windings as ladder circuit of coils is developed. A method for determining the primary parameters of ladder equivalent circuits is presented.

11

Authors: Mohamed Benkahla, Rachid Taleb, Zinelaabidine Boudjema

This article presents the powers control of a variable speed wind turbine (WT) based on a doubly fed induction generator (DFIG) because of their advantages in terms of economy and control. The considered system consists of a double fed induction generator whose stator is connected directly to the network and its rotor is supplied by seven-level inverter with structure NPC are well used to minimize the harmonics absorbed by the DFIG. In order to control the power owing between the stator of the DFIG and the grid. Have been studied and compared two types of controllers : Sliding Mode Control (SMC) and Fuzzy SMC (FSMC). Their respective performances are compared in terms of power reference tracking, response to sudden speed variations, sensitivity to perturbations and robustness against machine parameters variations.

18

Authors: Mohamed Zellagui, Almoataz Youssef Abdelaziz

The paper presents a new hybrid global optimization algorithm based on Chemical Reaction based Optimization (CRO) and Di¤erential evolution (DE) algorithm for nonlinear constrained optimization problems. This approach proposed for the optimal coordination and setting relays of directional overcurrent relays in complex power systems. In protection coordination problem, the objective function to be minimized is the sum of the operating time of all main relays. The optimization problem is subject to a number of constraints which are mainly focused on the operation of the backup relay, which should operate if a primary relay fails to respond to the fault near to it, Time Dial Setting (TDS), Plug Setting (PS) and the minimum operating time of a relay. The hybrid global proposed optimization algorithm aims to minimize the total operating time of each protection relay. Two systems are used as case study to check the e¢ ciency of the optimization algorithm which are IEEE 4-bus and IEEE 6-bus models. Results are obtained and presented for CRO and DE and hybrid CRO-DE algorithms. The obtained results for the studied cases are compared with those results obtained when using other optimization algorithms which are Teaching Learning-Based Optimization (TLBO), Chaotic Di¤erential Evolution Algorithm (CDEA) and Modified Di¤erential Evolution Algorithm (MDEA), and Hybrid optimization algorithms (PSO-DE, IA-PSO, and BFOA-PSO). From analysing the obtained results, it has been concluded that hybrid CRO-DO algorithm provides the most optimum solution with the best convergence rate.

10

Authors: Nabiha Brik, Mourad Chamekh

In this work we consider a nonlinear elliptic partial differential equation, which is derived from an application of a nonlinear Schrödinger equation. Using a variational approach on this problem leads to an optimization problem with a nonlinear constraint. A numerical solution based on finite-element method is used. We propose a new iterative algorithm to relax this problem to a quadratic version.

11

Authors: Bilal Abderezzak

The new world energy policies encourage the use of renewable energy sources with clean technologies, and abandon progressively the fossil fuel dependence. Another energy generation trend called commonly the “Waste-to-Energy” solution, uses organic waste as a response for two major problems: energy generation and waste management. Thanks to the anaerobic digestion, the organic waste can provide a biogas composed essentially from Carbone dioxide (CO2) and Methane (CH4). This work aims essentially to help students, researchers and even decision makers to consider the importance of biogas generation. The proposed tool is the last version of our previous tool which is enhanced and completed. It presents the potential to produce biogas of any shortlisted kind of waste, including also some energy valorization ways. A technical economical data are introduced for eventual feasibility studies.