ORIGINAL_ARTICLE
SINGLE SWITCH BOOST DC-DC CONVERTER WITH HIGHER VOLTAGE GAIN
In this paper, a new approach of DC-DC boost converter has been designed with the aid of an additional inductor, diode and capacitor offering a flexibility in electrical performance and challenging cost problem. The analysis of the modified boost converter is found out an advantage of improving the voltage gain with various choice of loads without any limitations in the duty ratio. The principle operation of the modified boost converter for steady state response in continuous conduction mode is discussed. The performance of the proposed converter is compared to the conventional converter, as the experimental data in the laboratory tests show full agreement with the simulation results.
https://erjm.journals.ekb.eg/article_66385_27f30a77fe64f07291ff7a8ce22bb324.pdf
2016-07-01
181
190
10.21608/erjm.2016.66385
Boost converter
voltage gain
CCM
duty ratio
Nerveen M.
Tawfik
1
Electrical Engineering Department, Faculty of Engineering, Menoufia University, Shebin El-Kom (32511), Egyp
AUTHOR
Mohamed E.
Ibrahim
2
Electrical Engineering Department, Faculty of Engineering, Menoufia University, Shebin El-Kom (32511), Egyp
AUTHOR
Arafa S.
Mansour
arafamnsr@yahoo.com
3
Electrical Engineering Department, Faculty of Engineering, Menoufia University, Shebin El-Kom (32511), Egyp
AUTHOR
S. S.
Shokralla
4
Electrical Engineering Department, Faculty of Engineering, Menoufia University, Shebin El-Kom (32511), Egyp
AUTHOR
ORIGINAL_ARTICLE
EFFECT OF LOAD TYPE ON PV MODIFIED SINE WAVE INVERTER CHARACTERISTICS
As conventional energy sources near to be fully consumed soon, the interest in generating electricity from renewable energy sources increases rapidly especially from photo voltaic “PV” systems. To connect AC loads to a PV system, an inverter should be used to convert the DC output coming from the PV system to AC matching the load requirements. Modified sine wave “MSW” inverter is the most used type because of its low cost. The problem of using MSW inverter is that the load type affects the inverter performance. The object of this paper is to study the effect of different loads on the MSW inverter output waveforms. Throughout the present work, a simulation model for the PV system is built using MATLAB/SIMULINK. An experimental setup is implemented for verifying the simulation analysis. A comparison between the theoretical and experimental results confirms the validity of the simulation.
https://erjm.journals.ekb.eg/article_66386_11dfdaa54d11e1ee6c91dcb3f0eb84c1.pdf
2016-07-01
191
196
10.21608/erjm.2016.66386
PV module
MPPT
MSW inverter
THD
ORIGINAL_ARTICLE
A NOVEL FLC FOR PV ARRAYS CONNECTED TO THE UTILITY GRID
This paper provides a suitable fuzzy logic control (FLC) system for three-phase grid-connected photovoltaic (PV) system which aims to work at unity power factor and constant output voltage suitable with the grid for any PV side or grid side disturbances. Also by the control system, the (PV-common DC link) interface transfers the energy drawn from the PV array by keeping dc voltage constant. Also, FLC results are compared with conventional (PI) control at the same disturbances. The model contains a detailed representation of the main components of the system that are the PV arrays, the booster converter and the grid side inverter. A novel method for Maximum Power Point Tracking (MPPT) technique through fuzzy logic system is implemented and compared with INC MPPT technique. MPPT techniques are obtained under different temperature values and irradiation levels. Modeling and control is carried out using MATLAB-SIMULINK. The simulation results showed the control performance and dynamic behavior of the system at various disturbances such as three-phase short circuit at connection point, one line outage and irradiation variations
https://erjm.journals.ekb.eg/article_66387_6ec87f990d7e107bd30caa6aa402d6f8.pdf
2016-07-01
197
205
10.21608/erjm.2016.66387
PV arrays
Grid connected
MPPT
DC-DC boost converter
PI control
FLC
R.A.
Amer
1
Electrical Engineering Department,Faculty of Engineering Menoufiya University, Shebin El-Kom,Egypt
AUTHOR
A.M.
Afifi
2
Electrical Engineering Department,Faculty of Engineering Menoufiya University, Shebin El-Kom,Egypt
AUTHOR
G.A.
Morsy
3
Electrical Engineering Department,Faculty of Engineering Menoufiya University, Shebin El-Kom,Egypt
AUTHOR
ORIGINAL_ARTICLE
FUZZY LOGIC CONTROL FOR A PERMANENT MAGNET GENERATOR CONNECTED TO GRID
This paper presents modeling and simulation of direct driven permanent magnet generator (PMG) employed in wind energy conversion systems (WECS). The simulation of wind turbine and gridconnected-PMG is implemented under MATLAB-SIMLINK environment to study the system performance. In order to connect the PMG with the grid, set of full-scale converters are used. These converters consist of back-to-back voltage source inverters (generator side inverter and grid side inverter) connected through DC-link capacitor. This capacitor decouples the two inverters, allowing two separate control systems applied to them. In view of inverters control, firstly they are controlled using of proportional-integral (PI) control systems. The simulation results are obtained using this control strategy under different disturbances. Also, the design of fuzzy logic controllers (FLCs) instead of PI controllers is investigated. Simulation results show that the proposed FLC scheme is more effective for enhancing the stability of wind farms connected to grid during temporary network disturbances and randomly fluctuating wind speed compared with conventional PI controllers. This study introduces a better understanding of the real behavior and highlights the features of controlling PMGs in order to get better utilization of wind energy resources in the near future.
https://erjm.journals.ekb.eg/article_66388_4909123453c6992aae0705ef86f77fe4.pdf
2016-07-01
207
216
10.21608/erjm.2016.66388
Wind Energy Conversion System
grid connected PMG
PI control
Fuzzy logic control
A. S.
Zalat
1
Egyptian Electricity Transmission Company (EETC)
AUTHOR
R. A.
Amer
2
Electrical Engineering Dept., Faculty of Engineering, Menoufiya University, Shebin El-Kom, Egypt
AUTHOR
G. A.
Morsy
3
Electrical Engineering Dept., Faculty of Engineering, Menoufiya University, Shebin El-Kom, Egypt
AUTHOR
ORIGINAL_ARTICLE
STABILITY IMPROVEMENT OF A FULLY SUPERCONDUCTING GENERATOR BY FUZZY LOGIC CONTROL
Fully superconducting generator (FSG) is one of the promising applications of superconductors in electric power sector. Meanwhile, transient stability of FSG is an important issue in developing this new machine. An approach is suggested in this paper for the design of a fuzzy logic governor controller (FLC) as a possible mean to improve the FSG stability under transient conditions. In this approach, unsymmetrical nonlinear membership functions are used, while number of FLC parameters to be properly designed is 15 parameters, including scaling factors for input and output variables along with widths and centers of fuzzy sets of input variables. A genetic algorithm is used to optimally choose all these parameters. Simulation results show that the proposed FLC leads to a significant improvement in the transient stability and performance of a FSG connected to an infinite-bus.
https://erjm.journals.ekb.eg/article_66389_3932c5243c98e96568c477f292edea10.pdf
2016-07-01
217
222
10.21608/erjm.2016.66389
Fully superconducting generator
Fuzzy logic control
Genetic Algorithms
Transient stability
R. A. F.
Saleh
1
Electrical Engineering Department, Faculty of Engineering, Menoufiya University
AUTHOR
ORIGINAL_ARTICLE
STABILITY ENHANCEMENT OF A SUPERCONDUCTING GENERATOR USING AN OPTIMIZED SVC-BASED STABILIZER
An important aspect in developing superconducting generator (SCG) concerns stability following a major system disturbance. This paper presents a method for enhancing stability of a SCG connected to an infinite-bus system using one of FACTS devices. In this method, a static VAR compensator (SVC)-based stabilizer is designed in coordination with a governor controller (GC) to effectively damp the mechanical oscillations which arise in the system when subjected to a disturbance. A time response-based objective function is defined and the design problem of SVC-based stabilizer and GC is formulated into an optimization problem. Particle swarm optimization (PSO) technique is employed to find out an optimal set of parameters for SVC-based stabilizer and GC. Simulation results, damping torque analysis, and small signal analysis show that the proposed PSO-based control scheme provides more damping to the SCG, and enhances its stability over a range of operating conditions.
https://erjm.journals.ekb.eg/article_66390_ae488932d27730ab47ecd29f14bc19ff.pdf
2016-07-01
223
230
10.21608/erjm.2016.66390
Superconducting generator
Transient stability
FACTS
Particle Swarm Optimization
R. A. F.
Saleh
1
Electrical Engineering Department Faculty of Engineering, Menoufiya University
AUTHOR
ORIGINAL_ARTICLE
RESPONSE OF THE RAFT FOUNDATIONS UNDER DYNAMIC LOADS
Modern industrial construction practice requires solutions to many problems concerning machine foundations. Modern manufacturing facilities have hammers, presses and turbines according to their production machinery. Vibrations due to machines may cause damage to structures nearby or even to machines themselves. These effects may extend to the surroundings and affect laborers and other sensitive machines within same place or neighboring residential areas. The Vibration amplitude and the forces transmitted to the supporting medium can become the governing factor of the foundation of these machines. So knowledge of the dynamic behavior of the foundation is important. The energy transmitted through soil and the response of the foundation system is essential for proper design of the system. This paper analyzes the response of a rigid raft foundation rested on the soil to eccentric harmonic, periodic and impulse forces (impact load).
https://erjm.journals.ekb.eg/article_66391_b5e102524e82dd46c021720291a827b3.pdf
2016-07-01
231
241
10.21608/erjm.2016.66391
Response
raft foundations
dynamic stiffness
damping
shear modulus
Mathematica
Fourier expansion: harmonics
E. A.
El-Kasaby
1
Prof. of soil mechanics and foundations. in Civil Engineering Department Benha Faculty of Engineering, Benha University, Cairo, Egypt.
AUTHOR
M. D.
Khedr
2
Lecturer. in Basic Engineering Sciences Department Benha Faculty of Engineering, Benha University, Cairo, Egypt.
AUTHOR
M. H.
Mansour
3
Lecturer in Civil Engineering Department Benha Faculty of Engineering, Benha University, Cairo, Egypt.
AUTHOR
Mona I.
Badawi
4
Demonstrator in Civil Engineering Department Benha Faculty of Engineering, Benha University, Cairo, Egypt.
AUTHOR