Naggar Saad

Ain Shams University · Department of Electrical Power and Machines

Multilevel inverter is increasingly utilised for DC/AC conversion in multiple electrical power applications due to its wide capabilities, low switching losses, and reduced output harmonics. Multilevel inverter faces some problems related to complex control, and high number of components. This paper presents a modified multilevel inverter topology t...

The Photovoltaic system is a sustainable renewable resource that attracts the attention of analysts in current decades. As the ambient conditions change over time as temperature and radiation rise, therefore, the productive power of the system is affected. Since the efficiency of this system is low due to these changes, and to get away from that mu...

The recent global status reports of Renewable Energy Source (RES) show that, wind and solar energy have the highest growth rate and installation capacities among all other renewable sources. In addition, reviewing the recent related researches proves that, combining two or more renewable energy sources in hybrid topology can increase the total syst...

Wind energy has the fastest and highest growth rate of any other Renewable energy sources (RES). Investigating the Wind Energy Conversion Systems (WECS) is very important for improving efficiency. However, It is required a monumental accessible land space for installing Wind turbines(WT). Consequently, this paper presents the design and implementat...

Wind energy has the fastest and highest growth rate of any other Renewable energy sources (RES). Investigating the Wind Energy Conversion Systems (WECS) is very important for improving efficiency. However, It is required a monumental accessible land space for installing Wind turbines(WT). Consequently, this paper presents the design and implementat...

Without question combining two or more renewable energy sources (RES) in hybrid topology can increase the overall system reliability and efficiency especially if they have a complementary nature. However, most RES has an intermittent nature of energy production due to dependency on weather conditions. Therefore, there are big challenges for coordin...

Enhancing the PV power requires necessity to track the MPP robustly. Most techniques implemented to obtain MPPT have some drawbacks, one of them is the oscillation around the operating point. This paper suggests sliding mode control technique to minify this problem. The strategy of SMC is designing a sliding surface which set the operating point. R...

According to numbers and charts reported recently in the global renewable status and international energy agency, Renewable energy sources (RES) surpassed the natural gas and occupied the second position as a source of electricity. However, the intermittent nature of RES, causes a big problem of trifold dimensions: System cost, environmental impact...

This paper presents Photovoltaic (PV) connected to single phase grid based on maximum power point tracking .paper related with how to solve problems caused by unconformity phenomena as like partial shading condition (PSC) which the photovoltaic always be in most time .In order to enhancing the efficiency of tracking global maximum power point under...

Abstract: Resonant DC-DC converters have been used widely as efficient alternatives for traditional DC-DC converters that suffer from the problems of high switching losses and low power density. Resonant converters implement soft switching mechanisms like zero current switching (ZCS) and zero voltage switching (ZVS) which allows for high frequency...

This paper proposes a novel hybrid centralized and distributed control of hybrid renewable energy system consisting of AC/DC micro grids. An Interlinking Converter (IC) is used to connect both sides of the micro grid systems together. Improved Particle Swarm Optimization (IPSO) which acts as a master controller is used to control the power of the s...

This paper proposes an improved fast dynamic system for controlling Matrix Converter (MC) based on modified hysteresis current controller using optimal tuning PI controller. An improved Bacterial Foraging Optimization (BFO) technique is employed for controlling the active and reactive current components of the Permanent Magnet Synchronous Generator...

Torque ripples and maximum power tracking form the most important problems facing Wind Energy Conversion System (WECS). This paper presents modified toque ripple minimization algorithm of four phases 8/6 poles Switched Reluctance Generator (SRG) using Artificial Neural Network (ANN) control. This control algorithm is based on optimum profiling of t...

Sensorless speed control of Permanent Magnet Synchronous Motor (PMSM) is still in development to eliminate the existing drawbacks such as speed ripples, torque ripples and slow response. This paper proposes Field Oriented Control (FOC) based on improved Model Reference Adaptive System (MRAS) to control the motor speed and minimize both the speed an...

Batteries arethepowertankofsolarpowersystems.Theyplaytheroleofpowersupplywhenthesun does notshine.Thispaperprovidesareviewofbatterychargingcontroltechniquesforphotovoltaic systems.Inaddition,itpresentsanewbatterychargecontrollerthatkeepsonthegoodfeaturesand resolvesthedrawbacksandlimitationsofthetraditionalcontrollers.Thenewcontrollerisbasedona new...

The main challenges of Wind Energy Conversion Systems (WECS) are to maximize the energy capture from the wind and injecting reactive power during the fault. This paper presents a current controlled matrix converter to interface Permanent Magnet Synchronous Generators (PMSG) based WECS with the grid. To achieve fast dynamic response with reduced cur...

Grid connected photovoltaic (PV) system encounters different types of abnormalities during grid faults; the grid side inverter is subjected to three serious problems which are excessive DC link voltage, high AC currents and loss of grid-voltage synchronization. This high DC link voltage may damage the inverter. Also, the voltage sags will force the...

The partial shading issue is one of the most critical problems facing the maximum power point tracking (MPPT) algorithms. This paper presents the design and implementation of a novel search technique for global maximum power point (GMPP) under partial shading conditions (PSC). It utilizes a two-stage algorithm to overcome the partial shading issue....

Nonlinear characteristic and internal behavior of the Proton Exchange Membrane (PEM) Fuel Cells under different load conditions is of paramount importance. This paper presents an adaptive neural controller based on a back-propagation algorithm for maximum power control of PEM fuel cell system. The system consists of a buckboost converter connected...

Nonlinear characteristic and internal behavior of the Proton Exchange Membrane (PEM) Fuel Cells under different load conditions is of paramount importance. This paper presents an adaptive neural controller based on a back-propagation algorithm for maximum power control of PEM fuel cell system. The system consists of a buck-boost converter connected...

Generally in photovoltaic applications the storage battery has the highest life time cost in the system; it has a profound affect on the reliability and performance of the system. The problem is that photovoltaic panels are not an ideal source for charging batteries. Maximum power point tracking (MPPT) will also be incorporated into the system, to...

Maximum power point tracking (MPPT) is necessary for photovoltaic (PV) systems to collect the maximum photovoltaic array power under variations in the insolation and temperature. This paper presentsan artificial neural controller for maximum power point tracking of photovoltaic system basedon back-propagation algorithm. The tracking algorithm c...

Generally in photovoltaic applications the storage battery has the highest life time cost in the system; it has a profound affect on the reliability and performance of the system. The problem is that photovoltaic panels are not an ideal source for charging batteries. Maximum power point tracking (MPPT) will also be incorporated into the system, to...

Wind Energy Conversion System (WECS) based on Doubly Fed Induction Generator (DFIG) connected to the grid is subjected to high transient currents at rotor side and rise in DC-link voltage during voltage sag at stator / grid side. To secure power system operation wind turbines have to meet grid requirements through the Low voltage ride through (LVRT...

The nanogrid is a small scale power system that consists of renewable and non-renewable power resources that supply power to nearby loads. The performance of the nanogrid is not totally satisfactory as large over shoot may occur in the output voltage, and current disturbances may occur at load side. Also power electronics system can become unstable...

This paper presents a simple electronic circuit for testing the photovoltaic (PV) modules by tracing their I-V characteristics. A precise PV module electrical model is also introduced. The circuit consists of a fast varying electronic load based on power MOSFET and operational amplifier. A DAQ system with LabVIEW application was developed for contr...

Nonlinear characteristic and internal behavior of the Proton Exchange Membrane (PEM) Fuel Cells under different load conditions is of paramount importance. This paper presents an adaptive neural controller based on a back-propagation algorithm for maximum power control of PEM fuel cell system. The system consists of a buck-boost converter connected...

The nanogrid is a small scale power system that consists of renewable and non-renewable power resources that supply power to nearby loads. The control structure of the nanogrid aims to schedule the sources, such that the non-renewable source improves the system reliability during the long-term shortage of the renewable source. This is achieved by D...

Mixing parameters off the Egyptian Mediterranean Coast in front off the Nile Delta are studied by a semi-empirical model of vertical turbulent mixing. The results model appear that the mixing rate decreases significantly with depth and turbulent kinetic energy plays a small role in mixing production. However, shear and viscous dissipation are essen...

The analysis of the turbulent mixing structure is accomplished by the dynamical computations of the mixing parameters represented by: buoyancy frequency (N), viscous dissipation (), turbulent kinetic energy (E), Richardson number (Ri), Reynolds stress, diffusive salt flux (DSF), diffusive heat flux (DHF). In general the computations show that, the...

‫ Surface currents induced by the combined effect of the wind stress over the sea surface, and the density distribution has been numerically modeled by Princeton Ocean Model, which is described fully by Mellor and Blumberg (1987). A horizontal resolution of 1'X1' has been used with seasonal time scale. The results show that the surface currents are...

This paper presents different schemes of state space vector pulse width modulation (PWM) for three-leg voltage source inverter. The analysis is performed with respect to switching losses and total harmonic distortion. Matlab /simulink programs are derived to illustrate the switching pattern for different schemes of space vector modulation (SVM). Th...

The performance of doubly fed induction generator (DFIG) variable speed wind turbine under network fault is studied using simulator developed in MATLAB/SIMULINK. Simulation results show the transient behavior of the doubly fed induction generator when a sudden short circuit at the generator bus is introduced. After the clearance of the short-circui...

Generally in photovoltaic applications the storage battery has the highest life time cost in the system; it has a profound affect on the reliability and performance of the system. The problem is that photovoltaic panels are not an ideal source for charging batteries. Maximum power point tracking (MPPT) will also be incorporated into the system, to...

This paper presents the steady state operation of the axial laminations switched reluctance motor (ALSRM). The performance of the motor is studied under constant speed operation and different values of both the switching turn on and off angles. The response of the motor is obtained at low, high, and very high speed in order to illustrate the perfor...

Maximum power point tracking (MPPT) is necessary for photovoltaic (PV) systems to collect the maximum photovoltaic array power under variations in the insolation and temperature. This paper presents an artificial neural controller for maximum power point tracking of photovoltaic system based on back- propagation algorithm. The tracking algorithm ch...

Using doubly fed induction generator (DFIG) for variable speed wind turbines has many advantages compared to other variable speed approaches. However, turbines with DFIG have complex operation principles and control. This paper describes the different steps for modeling and simulating the turbine behavior. Then simulation examples for studying the...

With the use of power electronic interface converters, renewable sources can be connected directly to a distribution network or combined with other local generators and loads to form an independent power system. As a promising topology for this application, resonant converters offer low switching losses due to zero voltage switching (ZVS) making th...