Mohamed Machmoum

Application of Power Line Communication for Data Transmission Over PWM Network

In industrial applications, a feedback loop is used in order to transmit control and diagnostic informations from the motor back to the inverter. The implementation of such feedback loop requires the use of extra cabling between both sides and that may have length exceeding few hundred meters. In this paper, the motor feeder cable is used for data transmission instead of the separated extra cable by using the power line communication (PLC) technology. However, beside the fact that feeder cables are not designed for data transmission, they are also polluted by the inverters outcome. Therefore, PLC modems developed for domestic applications may not be suitable. The aim of this study is to underline the possibility of communicating in such an environment. Limitations and difficulties that obstruct transmission are revealed. Also, possible solutions are discussed such as the use of a pulsewidth modulation filter in mean to overcome those limitations.

Control and optimization of shunt active power filter parameters by fuzzy logic

This paper presents the optimization of shunt active power filter parameters based on fuzzy logic control. The current active filter controller is based on constant or fuzzy hysteresis-band techniques, which are employed to derive the switching signals and also to choose the optimal value of the decoupling inductance. The dc voltage controller optimizes the energy storage of the dc capacitor, and proportional-integral and fuzzy logic controllers are developed and compared. Simulation results, obtained with MATLAB/Simulink simulation software configured under several loads, are presented and discussed to demonstrate the effectiveness of fuzzy logic controllers in optimizing the pulse-width modulation technique and reducing the values of the passive elements of the active power filter.

Determination of Voltage References for Series Active Power Filter Based on a Robust PLL System

Power quality (PQ) is one of the most important issues of modern electrical distribution. The series active filter can play a very significant role in the correction of PQ problems such as voltage unbalance, sag, interruption and voltage harmonics. This paper deals with the determination of voltage references for series active power filter based on a robust three-phase digital locked loop (PLL) system. Whatever the nature of supply voltages perturbation, the PLL block allows to extract fundamental positive sequence voltages system on the common coupling point and to estimate the mains frequency. Various regulators PI, RST and fuzzy logic are studied and compared in order to assure good reliability, a fast tracking performances and a good attenuation of undesirable frequencies. The robustness of the regulators allows the PLL operating under non ideal conditions and provides good results under unbalanced and/or distorted supply voltages conditions. Simulation results are presented to confirm the validity of the proposed design.

Design of Low-Speed Slotted Switched Reluctance Machine for Wind Energy Applications

This article describes the design of a low speed slotted switched reluctance machine (SSRM) for wind turbine applications. The modeling and the dimensioning of the machine structure are investigated. Teeth shapes are studied by maximizing the produced torque, and then the global design is analyzed by optimizing the mass to torque ratio. The influence of the number of poles per phase is investigated, and finally a comparison with other high torque machines is carried out. Dimensions are obtained thanks to a genetic algorithm (GA) associated to the finite element method for the resolution of the electromagnetic equations.

Marine tidal current systems: State of the art

The Ocean, which covers two-thirds of the world, captures and stores huge amounts of energy. Several sources of energy can be used. This paper presents a brief review of state of the art on the marine tidal current generation technology. The purposes are as follow: the first part concerns the conversion of marine current energy into mechanical energy, a synthesis of the existing methods of the modeling of the resource and of the marine current turbine are presented. The second part is dedicated to the conversion of the mechanical energy to electrical energy by taking into account the power converters for the control and the grid connection. Some simulation results are briefly shown for each part.

A fuzzy hysteresis voltage and current control of an Unified Power Quality Conditioner

This paper presents a new control design of an unified power quality conditioner (UPQC) for harmonics and voltage compensation in a power distribution system. The topology of the UPQC is based on a combination of two 3-phase series and parallel active power filters. The determination of voltage references for series active power filter is based on a robust three-phase digital phase locked loop (PLL) system using fuzzy regulator. Control strategies related to fuzzy hysteresis band voltage and current control methods, where the band is modulated with the system parameters to maintain the modulation frequency nearly constant are developed. Simulation results based on MATLAB/SIMULINK are presented to verify the effectiveness and the viability of the proposed control technique.

Optimization of the Connection Topology of an Offshore Wind Farm Network

In this paper, an approach based on a genetic algorithm is presented in order to optimize the connection topology of an offshore wind farm network. The main objective is to introduce a technique of coding a network topology to a binary string. The first advantage is that the optimal connections of both middle- and high-voltage alternating-current grids are considered, i.e., the radial clustering of wind turbines, the number and locations of the offshore electrical substations, and the number of high-voltage cables. The second improvement consists of removing infeasible network configurations as designs with crossing cables and thereby reduces the search space of solutions.

State of the art in tidal current energy extracting technologies

The potential of electric power generation from tidal currents is enormous. Tidal currents are being recognized as a resource to be exploited for the sustainable generation of electrical power. The high ocean water density leads to that tidal current turbine blades size are much smaller than wind turbine blades for the same power level. Additionally, tidal source is highly predictable for long time. Those characteristics make tidal current extremely promising and advantageous for power generation when compared to other renewable energy resources. The technology used for harnessing tidal current energy mainly based on the relevant work which has been carried out on ships propellers, wind turbines and on hydro turbines. This paper reports tidal power fundamental concepts and two currently used source modeling methods. The most promising tidal turbine projects worldwide are classified depending on the structure of turbine and some brief notes are given. Furthermore, it will also discuss the possible generator choices and system topologies.

Modeling and Vector Control of Marine Current Energy Conversion System Based on Doubly Salient Permanent Magnet Generator

This paper provides a model and a control of a marine current energy conversion system. The modeled marine current energy conversion system is a 10-kW generating system with a low-speed doubly salient permanent magnet generator of 50rpm. First, the resource, the turbine, and a dynamic analytical model of the generator are developed. Second, due to variations of marine current speed, which may lead to strong fluctuations in the power extracted by the marine current turbine, control strategies for the marine current energy conversion system at both low and high marine current speeds are analyzed, assessed, and compared. Finally, simulations of the proposed system are carried out, modeled, and simulated on MATLAB/Simulink software.

Optimization and Reliability Evaluation of an Offshore Wind Farm Architecture

This paper presents an original approach aiming to obtain the optimum configuration of an offshore wind farm (OWF). Thanks to cost models, we take into account the costs off all the parts of the electrical network. The optimization platform, based on a genetic algorithm, also allows us to evaluate the reliability of an OWF. This approach is used to compare the topologies obtained in different cases on a real OWF, the “Banc de Guerande.” The selected design of the OWF is compared to the results obtained using different methods: cost optimization, or both cost and reliability optimization. The optimization results show that the ring topologies give interesting results if the total cost including the expected energy not supplied during the lifetime of the OWF are taken into account. The number of offshore substations and their positions are also considered in the optimization: we show that the introduction of more substations in order to obtain better performances is possible at a reasonable cost. The presented optimization tool can help to design such farms taking into account several constraints.