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Sakar S.,Lulea University of Technology | Balci M.E.,Balikesir University | Abdel Aleem S.H.E.,15th of May Higher Institute of Engineering | Zobaa A.F.,Brunel University
Electric Power Systems Research | Year: 2017

Adding new capacity expansion alternatives using distributed generation (DG) technologies, particularly penetration of renewable energy, has several economical, and technical advantages such as the reduced system costs, the improved voltage profile, lower line loss and enhanced system's reliability. However, the DG units may lead to power quality, energy efficiency, and protection problems in the system when their penetration exceeds a particular value, generally called as the system's hosting capacity (HC) in the literature. In this paper, the HC determination of a distorted distribution system with Photovoltaic (PV)-based DG units is handled as an optimization problem by considering over and under voltage limitations of buses, current carrying capabilities of the lines, and harmonic distortion limitations as constraints. It is seen from simulation results that the HC is dramatically decreased with the increment of the load's nonlinearity level and the utility side's background voltage distortion. Accordingly, a C-type passive filter is designed to maximize the harmonic-constrained HC of the studied system while satisfying the constraints. The results indicate that higher HC level can be achieved using the proposed filter design approach compared to three conventional filter design approaches as voltage total harmonic distortion minimization, line loss minimization and power factor maximization. © 2017 Elsevier B.V.


Kandil S.S.,PSP El Sewedy | Aleem S.H.E.A.,15th of May Higher Institute of Engineering | Ibrahim A.M.,Cairo University
2016 18th International Middle-East Power Systems Conference, MEPCON 2016 - Proceedings | Year: 2016

In the literature, passive filters have been commonly used to mitigate the harmonic currents in industrial distribution systems because they are inexpensive, simple, and reliable. The aim of this paper is presenting different design methods for multiple-arm shunt passive filters based on various reactive power sharing approaches for an industrial distribution system of a petrochemical plant in Egypt. Eight techniques are presented, and their technical performance is assessed based on different indices such as power factor correction, filtering, voltage attenuation, distortion levels, and filter outage risks. Additionally, filters cost are considered in the comparison to decide the most economical technique. Modeling and simulation results of the case study are carried out in MATLAB and ETAP environments. © 2016 IEEE.


Mostafa M.F.A.,Egyptian Civil Aviation Authority | Aleem S.H.E.A.,15th of May Higher Institute of Engineering | Ibrahim A.M.,Cairo University
2016 18th International Middle-East Power Systems Conference, MEPCON 2016 - Proceedings | Year: 2016

Using solar photovoltaic (PV) systems at airports is one of the complex tasks due to their impacts on pilots, air-traffic controllers, aircraft, and air navigation systems. Glare reflection, electromagnetic waves, and wildlife hazards are examples of the expected risks that may take place and potentially affect the safety of the air transportation system. On the other hand, airports have wide areas that could be used to install a solar PV project. In this paper, the possibility of using solar PV systems at Egyptian airports is presented and discussed, taking into account the security requirements as mandatory conditions for the airport environments. The expected problems and their possible solutions are discussed. Examples of international airports using solar PV systems are illustrated. Additionally, a pre-feasibility study for using a PV system at an Egyptian airport (Hurghada International Airport) is proposed. The results indicate that the Egyptian airports can play an effective role in producing renewable energy through the use of solar PV systems. Besides, economic and environmental benefits can be achieved under certain conditions. © 2016 IEEE.


Mostafa M.F.A.,Egyptian Civil Aviation Authority | Aleem S.H.E.A.,15th of May Higher Institute of Engineering | Zobaa A.F.,Brunel University
2016 18th International Middle-East Power Systems Conference, MEPCON 2016 - Proceedings | Year: 2016

Many airports have become aware of the environmental benefits of using renewable energy resources, and they have focused their efforts on introducing solar photovoltaic (PV) systems on their available free land. Compared to other renewable energy technologies, solar PV arrays are the most suitable technology for airports. Because of the mandatory security requirements at airports, using solar PV is still a complex task because of the possible risks to aviation safety and air transportation systems. Glare due to the reflection of sunlight from the metal parts of a solar PV panel, electromagnetic interference with radar and other navigational aids, wildlife hazards, and the detachment of PV parts are the most common potential risks that could affect aviation safety. In this paper, the emerging safety concerns related to the installation of large-scale PV systems at airports are presented and discussed. Risk assessment matrices with the identification of risks and their potential consequences are demonstrated. In addition, possible mitigation solutions are provided to advance the state of knowledge on this issue. Based on the results gained from the proposed matrices, it is concluded that there is a significant opportunity to use solar PV at airports while complying with the aerodrome boundaries. This can be achieved using special procedures in PV design, installation, and maintenance to overcome the related potential risks. © 2016 IEEE.


Madboly D.A.,Spectrum | Aleem S.H.E.A.,15th of May Higher Institute of Engineering | Ibrahim A.M.,Cairo University
2016 18th International Middle-East Power Systems Conference, MEPCON 2016 - Proceedings | Year: 2016

In this work, a comparative study of different configurations of renewable distributed generation (DG) for green building in Egypt is proposed. The considered DG systems are stand-alone photovoltaic (PV) system with an energy storage facility, wind system with an energy storage facility, a hybrid system of PV-Wind-Battery, with and without the use of diesel generators, where diesel generators are used for reliability and security requirements. A proper configuration that meets the considered building's electric power demand with minimum cost over the lifetime of the system is proposed and discussed. The Hybrid Optimization Model for Multiple Energy Resources (HOMER) software is used to determine the optimal sizing of the considered renewable units. Additionally, due to the intermittent nature of these renewable resources, loss of power supply probability (LPSP) index has been taken in account while calculating the optimal sizing of the proposed DG system to assess the system reliability level. © 2016 IEEE.


Abdel Aleem S.H.E.,15th of May Higher Institute of Engineering | Balci M.E.,Balikesir University | Sakar S.,Gediz University
International Journal of Electrical Power and Energy Systems | Year: 2015

In the literature, it is well known that transformers and cables have excessive losses or overheating under non-sinusoidal current conditions. Accordingly, they have reduced current carrying capabilities (or loading capabilities) for that kind of conditions. This paper aims to employ passive filters for the effective utilization of the cables and transformers in the non-sinusoidal systems. Consequently, an optimal passive filter design approach is provided to maximize the power factor expression, which takes into account frequency-dependent line losses, under non-sinusoidal background voltage and line current conditions. The individual and total harmonic distortion limits placed in IEEE standard 519 are taken into account as constraints for the proposed approach. Besides, keeping the load's displacement power factor at an adequate range is desired by the proposed approach. The proposed approach and the traditional optimal passive filter design approach, which aims to maximize the classical power factor expression, are comparatively evaluated for an industrial power system with a group of linear and non-linear loads, overhead transmission lines, cables and a transformer. Numerical results show that the proposed one has a considerable advantage in the improvement of the total supply line loss and the transformer's loading capability under non-sinusoidal conditions when compared to the traditional one. On the other hand, for the simulated system cases, both approaches lead to almost the same current carrying capability value of the cables. © 2015 Elsevier Ltd. All rights reserved.


Aleem S.H.E.A.,15th of May Higher Institute of Engineering | Balci M.E.,Balikesir University | Zobaa A.F.,Brunel University | Sakar S.,Gediz University
Proceedings of International Conference on Harmonics and Quality of Power, ICHQP | Year: 2014

Transformers and cables have overheating and reduced loading capabilities under non-sinusoidal conditions due to the fact that their losses increases with not only rms value but also frequency of the load current. In this paper, it is aimed to employ passive filters for effective utilization of the cables and transformers in the harmonically contaminated power systems. To attain this goal, an optimal passive filter design approach is provided to maximize the power factor definition, which takes into account frequency-dependent losses of the power transmission and distribution equipment, under non-sinusoidal conditions. The obtained simulation results show that the proposed approach has a considerable advantage on the reduction of the total transmission loss and the transformer loading capability under non-sinusoidal conditions when compared to the traditional optimal filter design approach, which aims to maximize classical power factor definition. On the other hand, for the simulated system cases, both approaches lead to almost the same current carrying (or loading) capability value of the cables. © 2014 IEEE.


Abdel Aleem S.H.E.,15th of May Higher Institute of Engineering | Zobaa A.F.,Brunel University | Abdel Mageed H.M.,National Institute for Standards of Egypt
Energy Policy | Year: 2015

Energy is one of the most important categories in the Green Building Rating Systems all over the world. Green Building is a building that meets the energy requirements of the present with low energy consumption and investment costs without infringing on the rights of forthcoming generations to find their own needs. Despite having more than a qualified rating system, it is clear that each system has different priorities and needs on the other. Accordingly, this paper proposes a methodology using the Analytic Hierarchy Process (AHP) for assessment of the energy credits through studying and comparing four of the common global rating systems, the British Building Research Establishment Environmental Assessment Method (BREEAM), the American Leadership in Energy and Environmental Design (LEED), the Australian Green Stars (GS), and the PEARL assessment system of the United Arab Emirates, in order to contribute to the enhancement of the Egyptian Green Pyramid Rating System (GPRS). The results show the mandatory and optional energy credits that should be considered with their proposed weights according to the present and future needs of green Egypt. The results are compared to data gathered through desk studies and results extracted from recent questionnaires. © 2015 Elsevier Ltd.


Abdel Aleem S.H.E.,15th of May Higher Institute of Engineering | Zobaa A.F.,Brunel University
Electrical Engineering | Year: 2016

Single-tuned passive filters offer reasonable mitigation for harmonic distortion at a specific harmonic frequency with a high filtering percentage, but resonance hazards exist. Traditional damped filters offer high-pass filtering for the high-frequency range, but suffer from extra ohmic losses. C-type filters may operate in a manner similar to the tuned filters with low damping losses and marginal resonance damping capabilities. In addition, they can be designed as damped filters with increased resonance damping capability. In this paper, a methodology that facilitates sizing for the C-type damped filter parameters for harmonics mitigation and resonance damping in balanced distribution system networks is presented and discussed using the impedance-frequency index. This index evaluates the resonance damping capability provided by the damped filters analytically rather than the conventional graphical method of impedance-frequency scanning. It shows how to size shunt passive filters, while making a full use of their damping capabilities. It can disclose the parallel resonance frequencies of the equivalent system-filter impedance. A comparative study of the new approach and a conventional filter design approach, which aims to minimize total harmonic current distortion, is presented. Numerous simulation results are provided to clarify the proposed methodology, advantages, and disadvantages. © 2016 Springer-Verlag Berlin Heidelberg


Mousa A.G.E.,Cairo University | Abdel Aleem S.H.E.,15th of May Higher Institute of Engineering | Ibrahim A.M.,Cairo University
International Review of Electrical Engineering | Year: 2016

Any photovoltaic solar generator (PVSG) can be effectively utilized if it operates at its optimal operating point. Accordingly, many tracking algorithms for maximum power point tracking (MPPT) of photovoltaic (PV) modules had been developed. In the literature, the Perturbation and Observation (P&O) method and the Incremental Conductance (IC) method are the most widely used. Each of them has its unique advantages and disadvantages. In this paper, a maximum power point tracking algorithm method based on the analysis of the mathematical relationship among the maximum power points and the corresponding currents at different operating conditions, is presented. Several simulation results are provided to highlight the performance, effectiveness, advantages and disadvantages of the presented method compared to the conventional P&O and IC methods. Besides, a solar powered water pumping system is presented and discussed as an application of the different given MPPT techniques. © 2016 Praise Worthy Prize S.r.l. - All rights reserved.

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