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Soliman, A., D. K. Ibrahim, and O. E. Gouda, "Parameters affecting the arcing time of HVDC circuit breakers using black box arc model", IET Generation, Transmission & Distribution, vol. 13, issue 4, pp. 461 – 467, 2019. AbstractWebsite

Arc interruption of high voltage direct current (HVDC) circuit breakers (CBs) is one of the main challenging factors for using HVDC grids. To evaluate the arc interrupting capability in HVDC CBs, black box arc models are used to represent the nonlinear arc conductance depending on Cassie and Mayr dynamic arc equations. Extensive simulation studies are carried out to investigate the effect of controlled and uncontrolled parameters on the CB arcing time. A real line represents a part of 500 kV electrical connection systems between Egypt and the Kingdom of Saudi Arabia is simulated to be a faulty load. It is found that the arcing time of the HVDC CB can be reduced by increasing the value of cooling power coefficient (p) and decreasing the value of arc time constant (τ). It is also deduced that the arcing time is reduced by the increase of the commutation capacitance value (C) and decreasing the commutation inductance (L) value and vice versa. Moreover, it is concluded that the arcing time is greatly affected by the fault location and the fault arc resistance (Rf) according to fault conditions.

Boghdady, T. A., I. A. Sweed, and D. K. Ibrahim, "Performance Enhancement of Doubly-Fed Induction Generator-Based-Wind Energy System", International Journal of Renewable Energy Research, vol. 13, issue 1, pp. 311-325, 2023. AbstractWebsite

Nowadays, the challenging errand is enhancing the wind energy system (WES) performance to be more competitive and economically viable. One of the best ways to enhance the performance of the doubly-fed induction generator (DFIG)-based-WES is the optimization of the proportional-integral (PI) controllers for the variable frequency converter system. Many objectives with different optimization techniques have been used in literature to achieve optimal performance. Each choice has its advantages and disadvantages. This paper presents a new design approach for better performance of PI controllers and, hence DFIG over a wide range of operating conditions through two main themes. The first is by introducing a new multi-objective formulation, while the second is utilizing recent optimization techniques like Grey Wolf Optimizer and Whale Optimization Algorithm. Four PI controllers are optimized using a traditional objective function and the proposed multi-objective formulation. Two are related to the Rotor Side Converter (RSC), named power regulator, and the main rotor side converter current regulator. The other two PI controllers related to Grid Side Converter (GSC) are the DC-link voltage regulator and the main grid-side converter current regulator. A performance comparison is held through normal and abnormal operating conditions on a simulation model of a 6 MW wind farm located in Jabal Alzayt along the Red Sea Coast in Egypt and directly connected to the grid. The results confirmed the effectiveness of the proposed approach to help the DFIG-based-WES to agree with the Egyptian Grid Code during disturbances compared with the traditional objective formulation.

Abdel Aziz, M. M., E. S. T. E. Din, D. K. Ibrahim, and M. Gilany, "A phasor-based double ended fault location scheme for aged power cables", Electric Power Components and Systems, vol. 34, issue 4: Taylor & Francis, pp. 417-432, 2006. AbstractWebsite

This paper presents a fault location scheme for aged power cables using phasor measurements from both ends of the cable line. The proposed fault location scheme is derived using two-terminal measurements incorporated with a distributed line model, modal transformation theory, and discrete Fourier transforms. The proposed scheme can solve the problem of cable changing parameters, especially the change of the relative permittivity and thus for the operating positive, negative, and zero sequence capacitance changes. Extensive simulation studies are carried out using the alternative transients program ATP/EMTP. The simulation studies show that the proposed scheme provides a high accuracy in fault location calculations under various system and fault conditions. The results show that the proposed method responds very well, being insensitive to fault type, fault distance, fault resistance, and fault inception angle. The
proposed scheme solves the problem of aged cables with change of electric parameters. In addition, it gives an accurate estimation of the fault resistance in all fault types.

Din, E. S. T. E., M. Gilany, M. M. Abdel Aziz, and D. K. Ibrahim, "An PMU double ended fault location scheme for aged power cables", Power Engineering Society General Meeting, 2005. IEEE: IEEE, pp. 80-86, 2005. Abstract

This paper presents an adaptive fault location scheme for aged power cable using synchronized phasor
measurements from both end of the cable line. The proposed fault location scheme is derived using the two-terminal synchronized measurements incorporated with distributed line model, modal transformation theory and Discrete Fourier Transform. The proposed scheme has the ability to solve the problem of cable changing parameters especially the change of the relative permittivity over its age and thus for the operating positive, negative, and zero-sequence capacitance changes. Extensive simulation studies are carried out using Alternative Transients Program ATP/EMTP. The simulation studies show that the proposed scheme provides a high accuracy in fault location calculations under various system and fault conditions. The results show that the proposed method responds very well insensitive to fault type, fault resistance, fault inception angle and system configuration. The proposed scheme solves the problem of aged cables with change of its electric parameters. In addition to, it gives an accurate estimation of the fault resistance.

Gilany, M. I., E. M. T. Eldin, M. M. Abdel Aziz, and D. K. Ibrahim, "A pmu-based fault location scheme for combined overhead line with underground power cable", 3rd IEE International Conference on Reliability of Transmission and Distribution Networks (RTDN 2005): IET Digital Library, pp. 255-260, 2005. Abstract
Alham, M. H., M. F. Gad, and D. K. Ibrahim, "Potential of Wind Energy and Economic Assessment in Egypt Considering Optimal Hub Height by Equilibrium Optimizer", Ain Shams Engineering Journal, vol. 14, issue 1, pp. Article no.101816, 2023. Abstract

In Egypt, the wind market increases quickly to make it one of the top countries in the Middle East. This
study discusses the viability of wind resources and the economic assessment for four locations in Egypt:
Ras El-Hekma, Farafra, Nuweiba, and Aswan through two stages. In the first stage, the optimal hub height
for some wind turbines has been calculated by using Equilibrium Optimizer (EO) algorithm to achieve
maximum wind energy with overall minimum cost. The second stage, the economic assessment has been
evaluated by using such turbines to calculate the cost of energy (COE) compared to the global and
Egyptian production costs of wind energy. Developed MATLAB programs are applied for statistical analysis
of wind data. The results have shown that Ras El-Hekma’s average wind speed is higher than other
sites and its wind energy potential is the best. Moreover, the economic assessment for selected locations
turns out that Ras El-Hekma by using EWT-DW61/22 turbine has the lowest COE.

Younis, R. A., D. K. Ibrahim, E. M.Aboul-Zahab, and A. ’fotouh El'Gharably, "Power Management Regulation Control Integrated with Demand Side Management for Stand-alone Hybrid Microgrid Considering Battery Degradation", International Journal of Renewable Energy Research, vol. 9, issue 4, pp. 1912-1923, 2019. AbstractWebsite

A new Power Management Regulation Control (PMRC) integrated with Demand Side Management (DSM) strategies is proposed to enhance the Energy Management System (EMS) of a stand-alone hybrid microgrid. The microgrid combines Wind and PV systems as Renewable Energy Sources (RES) with a hybrid Energy Storage System (ESS) of Battery and Fuel Cell/Electrolyzer set. Towards achieving Net Zero Energy Supply, such microgrid is adequate in remote and isolated new communities with AC controllable critical and noncritical loads. The proposed PMRC implies two-levels of control based on Multi-Agent System (MAS). The first level keeps the output power of each source in its maximum available output power by applying maximum power point tracking (MPPT) techniques. The second level is based on making proper decisions for achieving the power balancing regulation and coordination between the available and the reserve power of the RES and ESS under different operating modes. Valley Filling, Energy Conservation and Load Shifting are applied as DSM strategies to improve loads sustainability during system contingencies. Considering the battery as the most expensive part in the microgrid, the effectiveness of the proposed strategy is further verified by determining the maximum permissible estimated battery lifetime during the operation in all possible scenarios. Extensive simulation studies for various scenarios of microgrid operation in a year were carried out using Matlab/ Simulink with realistic typical wind speed, solar irradiation data and restricted by the status of available ESS.

Dawoud, M. A., D. K. Ibrahim, M. I. gilany, and A. ’F. El’Gharably, "Proposed Application for Rate of Change of Phasor Voltage in Fault Detection and Coordination Studies in MV Distribution Networks", Iranian Journal of Science and Technology, Transactions of Electrical Engineering, vol. 45, issue 3, pp. 815–831, 2021. Abstract

Selectivity, reliability and security of electrical distribution systems are important issues in modern power systems. The protection coordination approach that depends on fault current only is no longer valid for medium voltage (MV) distribution systems; it has major limitations because of varying network conditions. In this paper, a new protective coordination technique is proposed in MV distribution networks. The proposed technique is based on calculating the rate of change of phasor voltage (ROCOV) in each feeder to discriminate and locate the faulty section. The measured ROCOV values and the required relay operating time take the shape of the standard inverse-time characteristics that are used for overcurrent relay. The system allows full coordination between the primary and backup relays. Without any need for communications, the proposed technique proved good robustness during different transient healthy conditions. The setting of the proposed relay does not need to be re-adjusted with the changes in network operating conditions since it depends on system voltage not the loading current. The proposed technique is tested using extensive MATLAB simulations under different faulty and healthy conditions in a MV distribution system. The results indicate that the proposed technique meets the fundamental protective requirements such as selectivity, reliability, sensitivity, and speed as well.

Ibrahim, I. M., D. K. Ibrahim, and E. E. D. A. El Zahab, "A Proposed Busbar Protection Scheme Immune to the Impact of Outflow Current during Internal Faults", International Middle-East Power Systems Conference (MEPCON), Helwan University, Egypt, December 27-29, 2016. Abstract

This paper describes a proposed busbar protection scheme immune to the impact of the outflow current during internal faults based on the combination of magnitude and phase angle comparisons. The effective relay performance is achieved by implementing the phaselet approach and the adaptive digital mimic filter. The performance of the proposed scheme is extensively analyzed for different fault conditions on a breaker and a half bus substation to ensure its proper response during internal, external and evolving faults. Tests are carried out to investigate the impact of the circulating current, CT saturation, fault inception angle and high fault resistance. ATP simulations ensure that the proposed scheme can fulfill all busbar protection requirements within quarter cycle operation time and is not affected by the outflow current during internal faults.

Mohamed, S. H., Z. H. H., I. D. Khalil, and A. E. L. - Z. E. EL-Din, "A Proposed Coordination Strategy for Meshed Distribution Systems with DG Considering User-defined Characteristics of Directional Inverse Time Overcurrent Relays", International Journal of Electrical Power & Energy systems, Elsevier, vol. 65: Elsevier, pp. 49-58, 2015. AbstractWebsite

In this paper, coordination strategy that considers using user defined characteristics for the inverse time overcurrent relays is proposed. Typically, the coordination between relays operating times within meshed systems are achieved by adjusting two relay settings; pick up current and time multiplier setting (TDS and Ip). The equation that models the digital inverse time overcurrent relay operation has two constants; one of them represents the constant for relay characteristics (A) and the other one represents the inverse time type (B). The proposed coordination strategy considers the two relay characteristics constants as continuous variable settings that can be adjusted. These (A and B) values are chosen optimally in addition to (TDS and Ip) to achieve coordination. The coordination problem is formulated as a nonlinear programming problem where the main objective is to minimize the overall time of operation of relays during primary and backup operation considering faults at different locations. The results are compared against the relay coordination using the conventional settings. The problem is applied to the meshed power distribution network of the IEEE 30 bus systems equipped with synchronous based DGs. The results show that the proposed strategy can significantly reduce the overall relay operating time and thus making it an attractive option for meshed distribution systems with DG.

El-Sonbaty, A. E. - S., H. K. M. Yonssef, and D. K. Ibrahim, "A proposed particle swarm optimization technique for solving non-linear economic dispatch problem", Power Systems Conference, 2006. MEPCON 2006. Eleventh International Middle East, vol. 2, El-Minia, Egypt, IEEE, pp. 606-611, 2006. Abstract

This paper proposes a particle swarm optimization (PSO) method for solving the economic dispatch (ED) problem in power systems. Many nonlinear characteristics of the generator are considered for practical generator operation, such as ramp rates, prohibited operating zones, and non smooth cost functions. The feasibility of the proposed .method is demonstrated for two different systems, and is compared with both Genetic Algorithm (GA) method and another PSO method in terms of the cost optimization and computation time where an improvement in both terms is achieved.

Dawoud, M. A., D. K. Ibrahim, M. I. gilany, and A. F. Abdel-Rheem, "A Proposed Passive Islanding Detection Approach for Improving Protection Systems", International Journal of Renewable Energy Research, vol. 10, issue 4, pp. 1940-1950, 2020. Abstract

Integration of Distributed Generation (DG) on the power system networks causes several difficulties, especially for the system protection. One of the important problems associated with system protection is the islanding that takes place when a DG unit (or group of units) continues to energize a part of the load separated from the main utility. As a result, many obstacles occur such as voltage and frequency fluctuation, in addition to personnel safety problems during maintenance. In this paper, the islanding problem is discussed and also the previous islanding detection techniques are investigated to get an efficient technique for islanding detection. The proposed technique is based on estimating the Rate of Change of Zero Sequence of Second Harmonic Voltage at the Point of Common Coupling (PCC). The proposed technique is extensively tested for inverter-based DG includes wind turbines with double-fed induction generator (DFIG). The proposed technique could distinguish the islanding operation correctly within only one cycle without non-detection zone (NDZ). In addition, it could differentiate between the islanding operation at different values for active and reactive power mismatch. Several scenarios are tested such as normal load variation, capacitor switching and power quality disturbances like voltage sags and swells. Faults and outage of one of DGs are also tested.

Mokhtar, N. M., H. Mohamed Sharaf, D. K. Ibrahim, and A. ’F. El’Gharably, "Proposed Ranked Strategy for Technical and Economical Enhancement of EVs Charging with High Penetration Level", IEEE Access, vol. 10, pp. 44738-44755, 2022. Abstract

Car exhaust is one of the most common causes of ozone hole aggravation, electrical vehicles (EVs) represent a promising solution to avoid this problem. Despite the benefits of EVs, their random charging behavior causes some difficulties regarding the electric network performance, such as increased energy losses and voltage deviations. This paper aims to achieve the proper scheduling of the EVs charging process, avoid its negative impacts on the network, and satisfy the EVs users’ requirements. The EVs charging process is formulated as an optimization problem and solved using particle swarm optimization. The optimization problem formulation considers the EV arrival and departure times and the state of charge required by the user. Different strategies such as separated, accumulated, and ranked strategies with continuous or interrupted fixed charging have been applied to solve the uncoordinated EVs charging problem. These strategies are extensively tested on the modified IEEE 31 bus system (499-node network), using the combination of both Open DSS and MATLAB m-files. The simulation results confirm the effectiveness of the proposed accumulated ranked strategy with interrupted fixed charging in improving the overall power system performance. The achieved improvements include minimizing: the peak power consumed, the peak power losses, and the voltage drop. Moreover, the cost of the EVs charging in most of the feeders has been decreased to a satisfying value. A comparison between the proposed strategy and some previously reported strategies has been performed to ensure the technical and economic enhancement of the proposed strategy.

Mohamed Sharaf, H., H. H. Zeineldin, D. K. Ibrahim, A. El Zahab, and E. El Din, "Protection coordination of directional overcurrent relays considering fault current direction", Innovative Smart Grid Technologies Conference Europe (ISGT-Europe), 2014 IEEE PES: IEEE, pp. 1–5, 2014. Abstract

Directional inverse time overcurrent relays are used in protection systems of meshed networks to operate for fault currents in its forward zone of operation. They are used for primary and backup protection and their operation needs to be coordinated to assure selectivity. Different optimization techniques have been used to select their settings to achieve protection coordination, however the optimal protection coordination problem formulation doesn’t consider the fault current direction to assure correct operation especially for
backup relays. This paper proposes the addition of fault current direction constraint to the formulation of the optimal directional inverse overcurrent relays coordination. The proposed formulation is tested on the distribution portion of the IEEE 30 bus system considering the effect of distributed generation addition. Results show that the proposed formulation gives more accurate optimal relay settings and thus highlighting the importance of inclusion of the proposed direction constraint in the protection coordination problem.

Radwan, M. M., R. S. Sharaf, and D. K. Ibrahim, "Providing Quality Mass Higher Education, the Egyptian Experience", IMHE General Conference: Attaining and Sustaining Mass Higher Education , Paris, France, 17- 19 Sep. 2012. Abstract

Over the last few decades, like many other countries around the world, Egypt is facing the challenge of the need to expand higher education enrolment, both for meeting the growing demand and also the realization of the importance of higher education in nation economic development. Since year 2000, Egypt worked on improving higher education through developing and implementing a comprehensive strategic plan adopting the principles of equity, quality and relevance, and responding to the current and future needs of social development, job market and production as one of the main goals. The establishment of the National Authority for Quality Assurance and Accreditation in Education (NAQAAE) in 2006 as an independent authority did set national quality standards to be met by higher education institutions for accreditation. The Program of Continuous Improvement and Qualifying for Accreditation (PCIQA) was initiated in 2007 by the Ministry of Higher Education for financing, through a competitive mechanism, and technically supporting higher education institutions to implement their strategic plans, fulfil accreditation quality criteria and assure continuous improvement. This paper reviews the Egyptian experience in providing mass higher education and assuring its quality, highlighting the innovative approaches adopted both on the national strategic policies and the individual institutions practice levels.