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Khalil, E., T. A. Boghdady, M. H. Alham, and D. K. Ibrahim, "A novel multi-objective tuning formula for load frequency controllers in an isolated low-inertia microgrid incorporating PV/wind/FC/BESS", Journal of Energy Storage, vol. 82, issue 30 March 2024, pp. Article no. 110606, 2024. AbstractWebsite

Load frequency control (LFC) is vital for isolated microgrids (IMGs), especially when uncertain renewable energy sources (RESs) are present. Enhancing LFC schemes relies mainly on three tracks. Adding new resources to IMG structures is the first track, designing novel controller structures for LFC schemes is the second, and the third is improving controller tuning procedures in the LFC schemes. This research suggests an innovative multi-objective formula (MOF) for controller tuning that combines a novel error criterion termed the integral-square time absolute error of frequency change with the integral-square of IMG controllers' signals. Tested IMG includes multi-sources of diesel engine generators, fuel cells, battery energy storage technologies, and RESs (like photovoltaic and wind turbines). The proposed MOF tuning is evaluated compared to four different objective functions, which are the integral-absolute error (IAE), integral-time absolute error (ITAE), integral-square error (ISE), and integral-time square error (ITSE). The proportional-integral-derivative (PID), fractional-order, and cascade PID controllers are implemented to appraise the proposed MOF extensively against all these single objectives. Statistical analyses are accomplished comprehensively to verify the effectiveness of the artificial rabbits' optimization algorithm (ARO) in competition with other recent optimization algorithms to tune different controllers utilized in the LFC schemes of the examined IMG based on tested objectives. Therefore, ARO is applied to optimize controller settings by combining system nonlinearities with IMG sources' maximal generation rate constraints. The comparative analysis considers settling times, overshoots, IAE, ITAE, ISE, and ITSE performance indices. MATLAB/Simulink simulations confirmed the ability of the suggested MOF tuning to stabilize the system and keep improving performance indices, significantly attaining the minimum settling time even for massive three-type load fluctuations. The first type is step disturbances ranging between 0.1 and 0.25 p.u, the second is varying step disturbances every 5 s, and the third is severe dynamic random load shifts from −0.2 to 0.2 p.u. In addition, the MOF outperforms other competitors' tuning formulas while adding fluctuations of RESs with load disturbances. Furthermore, the robustness analysis is conducted for the applied controllers based on the proposed MOF tuning approach by changing the IMG nominal parameters with ±25 % and adding system nonlinearities. The analysis ensured its efficacy in preserving system stability. Finally, the stability test in the frequency domain using the MATLAB/control design tool verified system stability when different LFC controllers were tuned based on the proposed MOF tuning.

Khalil, E. A., M. H. Alham, T. A. Boghdady, and D. K. Ibrahim, "Novel Single Loop Load Frequency Controller for Isolated Microgrid Via Geometric Mean Optimization", , 224th International Middle East Power System Conference (MEPCON), Egypt, 19-21 Dec. 2023. Abstract

In rapidly expanding isolated microgrids (IMGs), load frequency control (LFC) should ensure optimal power
quality for end users. In particular, renewable energy sources (RES) require robust and intelligently designed LFC systems for their stochastic nature. This study presents a novel single-loop
controller that combines a fractional order-proportional beside a tilt integral derivative with fractional order (FPTID) to improve the LFC of multi-source IMGs. Diesel generators, fuel cells, battery storage devices, and RES (solar and wind power generation) are included in the evaluated IMG. Recent geometric mean optimization adjusts FPTID controller parameters. Extensive MATLAB/Simulink simulations reveal that the FPTID controller outperforms numerous previously published controllers regarding the minimum error criteria, undershoots/overshoots/settling times, and frequency deviation in response to load and RES variations.

Hamza El-Sayed, K., D. K. Ibrahim, and E. E. - D. A. El-Zahab, "Operation and Control of 850kW Doubly Fed Induction Generators Based Al-Zafarana Egyptian Wind Farm", International Journal of Electrical Energy, vol. 4, issue 2, pp. 112-121, 2016. AbstractWebsite

With increasing global great concern over greenhouse gas emissions and their harmful effects on environment, huge number of wind turbines are recently connected to electrical grids. Nowadays, Egypt has continuous development of wind energy projects; it makes a great effort at Gulf of Suez area especially in Al Zafarana district. This paper focuses on studying the dynamic performance of the 5th phase of Al-Zafarana wind farm, which is made of 100 Gamesa G52/ 850kW Doubly Fed Induction Generator (DFIG) machines, using Digsilent /PowerFactory simulation tool as an advanced simulation package. As DFIG is currently one of the most common types employed for Wind Energy Conversion System (WECS), the paper also implements a dynamic model for 850 kW DFIG machine based WECS in Matlab / Simulink environment. A dual reference frame control strategy is applied here to improve the dynamic system performance during balanced and unbalanced grid voltage conditions.

Kamal Youssef, H., D. K. Ibrahim, and A. M. Abd El Fattah, "Optimal Allocation of SVC to Enhance Voltage Stability of Power Systems", Proceedings of the 8th International Conference on Electrical Engineering, ICEENG Conference, Military Technical College, Cairo, Egypt, 29-31 May, 2012, 2012. Abstract

This paper addresses the optimal allocation of Flexible AC Transmission Systems (FACTS) devices in a power system in order to improve voltage stability. With the continuous increase of power demand, FACTS provide a suitable solution by maximizing the usage of existing utilities rather than increasing power generation and building new lines. Due to high cost of such devices their optimal allocation must be ascertained. Particle swarm optimization (PSO) is used in this paper to determine the best location and size of Static VAR Compensator (SVC) where the objective function is to achieve the accepted voltage profile taking into consideration the SVC cost. Simulations are performed on IEEE-14 test system. Results prove the effectiveness of PSO in solving such allocation problem.

Fayoud, A. B., H. M. Sharaf, and D. K. Ibrahim, "Optimal coordination of DOCRs in interconnected networks using shifted user-defined two-level characteristics", International Journal of Electrical Power and Energy Systems, vol. 142, issue Part A, pp. Article no. 108298, 2022. Abstract

This paper introduces a protection scheme for interconnected networks based on proposed Directional Overcurrent Relays (DOCRs) with user-defined two-level characteristics. By getting usage of the capabilities available in modern digital DOCRs, the proposed relay will have two user-defined characteristics; one for its primary operation and another for its backup operation (two-level characteristics) to fit a specific application or system. The coordination between the proposed relays is formulated and solved as a non-linear optimization problem to minimize their operating time and reduce the thermal impact caused by short circuit currents through electrical equipment while maintaining the technical constraints.
Extensive comparative studies have been performed to ensure the effectiveness of the proposed protection
scheme. Firstly, the performance of the traditional one-level characteristic relay (COLC) with two settings is
compared to the conventional two-level characteristic relay (CTLC) with three settings. Then a further investigation is carried out by suggesting increasing the number of settings to seven, named as the user-defined two-level characteristic relay (UDTLC), and then to nine settings, named as the shifted-user-defined two-level characteristic relay (SUDTLC). Finally, different multi-objective functions with proper weighting factors are investigated to determine the most effective one with the best performance for the proposed idea.
The distribution portion of the IEEE 30-bus system has been used to test and verify the proposed characteristics extensively. The optimal coordination problem is solved using the fmincon function in MATLAB. Based on the achieved results, the proposed characteristics of UDTLC and SUDTLC guaranteed a considerable reduction in operating times. In addition, the achieved results deduced that using a different multi-objective formulation has little impact on reducing operating time due to using the proposed characteristics UDTLC and SUDTLC, which means solving the coordination problem is mainly dependent on the applied characteristics.

El-Nagar, M. M. K., D. K. Ibrahim, and H. K. M. Youssef, "Optimal Harmonic Meter Placement Using Particle Swarm Optimization Technique", Online J. Power and Energy Engineering, vol. 2(2), pp. 204-209, 2011, 2011. Abstract
Alham, M. H., M. Elshahed, D. K. Ibrahim, and E. E. D. A. El Zahab, "Optimal operation of power system incorporating wind energy with demand side management", Ain Shams Engineering Journal, vol. 8, issue 1: Elsevier, pp. 1-7, 2017. AbstractWebsite

The high penetration of the wind energy in the power systems raises some issues such as ramping and mismatch between the wind power and power demand. One of the possible solutions to these issues is the demand side management (DSM). In this paper, dynamic economic dispatch (DED) incorporating different penetration levels of wind energy and utilizing the DSM is proposed to solve the issues related to high penetration of wind energy. The effect of utilizing the DSM on the operation cost with different test cases is discussed. The General Algebraic Modeling System (GAMS) using BARON as a solver and genetic algorithm (GA) with hybrid function are used to solve the proposed DED model and a comparison between them is assessed. The proposed model is applied to a six units’ generation system to test the effectiveness of the proposed model.

Zeineldin, H. H., H. M. Sharaf, D. K. Ibrahim, and E. E. - D. AbouEl-Zahab, "Optimal Protection Coordination for Meshed Distribution Systems With DG Using Dual Setting Directional Over-Current Relays", IEEE Transactions on Smart Grid, vol. 6, no. 1: IEEE, pp. 115–123, 2015. AbstractWebsite

In the presence of distributed generation (DG), it is important to assure a fast and reliable protection system for the distribution network to avoid unintentional DG disconnection during fault conditions. In this paper, dual setting directional over-current relays are proposed for protecting meshed distribution systems with DG. Dual setting relays are equipped with two inverse time-current characteristics whose settings will depend on the fault direction. The protection coordination problem for the dual setting directional relay is formulated as a nonlinear programming problem where the objective is to minimize the overall
time of operation of relays during primary and backup operation.
The proposed protection coordination scheme using dual setting relays is compared against the conventional approach, which relies on the conventional one setting directional relay. The proposed scheme is applied to the power distribution network of the IEEE 30-bus system equipped with synchronous and inverter-based DG. The results show that the proposed protection coordination scheme with dual setting relay can significantly reduce the overall relay operating time, making it an attractive option for distribution systems with DG.

Gamal Mohamed, R., D. K. Ibrahim, H. Kamal Youssef, and H. H. Rakha, "Optimal Sizing and Economic Analysis of Different Configurations of Photovoltaic systems", International Review of Electrical Engineering, vol. 9, issue 1: Praise Worthy Prize, pp. 146-156, 2014. Abstract

This paper presents a comparative study between different configurations of photovoltaic (PV) systems which are the stand-alone (PV) system, the PV-diesel- battery hybrid system and the grid connected PV system. The main objective is to select the optimal system configuration for supplying the electrical load of an Egyptian isolated village. Design calculations are carried out using three different techniques which are: Heuristic approach, loss of power supply probability indices, and HOMER software analysis. The life cycle cost (LCC) analysis is also conducted to assess the economic viability of designed system. As for determining the optimal PV panels tilt angle, three cases are studied. The paper also shows the effect of electricity price on PV standalone system, and grid extension.

Gamal Mohamed, R., D. K. Ibrahim, M. M. Abdel Aziz, and H. Rakha, "Optimal Sizing and Economic Analysis of Stand-Alone Photovoltaic System", International Journal on Power Engineering and Energy, IJPEE, vol. 4, issue 2, pp. 378-384, 2013. AbstractWebsite

For the development of energy sources in rural regions in Egypt at the brink of the 21st century, it may be necessary to use solar energy in all applications as one of the most promising new, clean and renewable energy sources. This paper presents a study for a stand-alone photovoltaic (PV) system design to provide the required electricity for an isolated village in Mersa Matrouh, Egypt. The complete design of the suggested system is achieved by optimization techniques using different software. In addition to taking into account site radiation data and electrical load data of this typical village, the life cycle cost (LCC) analysis is also conducted to assess the economic viability of the designed system.

Gamal Mohamed, R., D. K. Ibrahim, M. M. Abdel Aziz, and H. Rakha, "Optimization and Life Cycle Cost of Stand-Alone Hybrid Energy System for Egyptian Isolated Village Using HOMER", Proceedings of the 15th International Middle East Power Systems Conference, MEPCON 2012; Alexandria, Egypt, December, 23-25, 2012., 2012. Abstract

The aim of this paper is to determine the possibility of using a stand-alone hybrid energy system to meet the electric load demand of an isolated area using HOMER Software. The combination of using remote area-diesel generators and renewable energy source such as photovoltaic system (PV) with a battery storage can greatly overcome some of diesel generators problems. In this paper, a PV/Diesel generator hybrid energy system is sized to meet the load with about 100 % availability. HOMER is used to optimize the operation of the diesel generator and to calculate the optimum number of the PV modules and batteries that would achieve the minimum initial cost and a desired depth of discharge for battery storage. As the economic issue is greatly concerned, it is necessary to identify the system life cycle cost or the Total Net Present Cost, TNPC, of the optimal hybrid energy system which can also be achieved by HOMER optimization. For observing the economic and technical feasibility of the designed power system and its economics, it is important to assess the effect of uncertainty or the change of several variables such as solar radiation, interest rate and fuel price which can be carried out by performing several sensitivity analyses.

Soliman, A. A. R. A. A., M. M. Sayed, and D. K. Ibrahim, "Optimized hybrid microgrid of gas generators-wind farm using crow search algorithm", Proceedings of the 2017 Saudi Arabia Smart Grid (SASG), 12-14 Dec. 2017, Jeddah, Saudi Arabia, 2017. Abstract
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.