Mohamed Barara

Flexible control for small power generation employing renewable energy source used in isolated communities

The controllability of the electrical production is the main problem of renewable energy generators due to uncontrollable meteorological conditions. This study examines the feasibility for an isolated small power generation based on renewable energy source able to supplying different type of loads AC and DC with regulated voltage. The complete system is modelled in Matlab\Simulink with three closed loops under fluctuation of the source (variable prime mover of the generators) and sudden application of loads. Both the DC voltage and AC voltage are controlled to the desired reference. The present results show the effectiveness and validity of the proposed power generation system.

Improvement performance of sensorless direct field oriented control induction motor drive with fuzzy logic controllers

This research aims to present a sensorless direct field oriented control (DFOC) with intelligent technique based on fuzzy logic controllers (FLC) to obtain fast response and to improve the dynamic performance of a three-phase induction motor drive (IM). These regulators are applied in speed, flux and stator currents control of induction motor. A Luenberger flux observer and speed adaptation are associated with the proposed scheme. Simulation results show that the proposed direct field oriented control with the proposed observer provides good performance dynamic characteristics for different operating modes. The robustness of the overall system is studied using simulation for load torque disturbance.

Fuzzy modeling magnetizing curve of a self excited induction generator and effect of mutual inductance

This paper presents a qualitative modeling for magnetization curve of self-excited induction generator and effect of mutual inductance. During self excitation the variation in the value of magnetizing inductance, increases until it reaches a peak value and decreases until it attains saturated value then increasing at lower voltage and then decreasing at higher voltage as presented. The application of fuzzy clustering method and a rule processing to extract the qualitative properties curve magnetizing of self excited induction generator.

Experimental dSPACE Analysis for Self-excited Induction Generator Used in Voltage Control

In this paper, a new approach is proposed for keeping the RMS voltage output constant, the system is supplying by a self-excited induction generator (SEIG) driven by a controlled DC motor with variable speed and load. The scheme used in this paper is based on a classical Proportional-Integral regulator wich controls a SPWM switching. A MATLAB Simulink model of the system is developed to maintain the AC voltage at the desired value. Then a comparison is examined between simulation and experimental results using dSPACE board. The results are provided to verify the effectiveness of this approach and it gives very high performance.

Modeling and simulation for a three-phase voltage source inverter using a self-excited induction generator

The induction machine used such a Self excited generator is the most popular for generating power from renewable energy sources, Their main weakness is poor voltage regulation under changeable load and speed, This paper present analysis of a control scheme for maintaining a three-phase load RMS voltage constant, fed by self-excited induction generator under variable speed and load. A simulation result demonstrates very good performance in tracking the output voltage at the desired value with a minimum THD.

Applied approach intelligent technique for speed control of induction machine

This paper presents a comparative study of an indirect field oriented control (IFOC) of induction machine (IM) using an integral-proportional (IP), sliding mode (SMC) and intelligent technique based on a fuzzy logic (FLC) controllers for speed regulation. The traditional integral-proportional controller is sensitive to the load torque disturbances. The fuzzy logic control is a part of intelligent control which contain hard and soft computing. The approach of sliding mode control utilizes discontinuous control laws to drive the system state trajectory into a sliding or switching surface in the state space. The effectiveness of the IP, fuzzy logic and sliding mode controllers was tested under different conditions such as reference speed and load torque disturbances. The simulation results demonstrate that the proposed controllers are better robust than the traditional IP controller.

Experimental analysis on a Self Excited Induction Generator for standalone wind electric pumping stations

Self Excited Induction Generator (SIEG) has become a focal point in the research of standalone renewable energy sources. This paper investigates the capacity and the applicability of self excited induction generator feeding an isolated non linear load (induction motor coupled with variable mechanical load) in order to exploited in the remote areas as wind electric pump system for different application. The performance characteristics are examined by experimental test, the transient, steady state and limit of operating is also discussed in this study.