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D
Alham, M. H., M. Elshahed, D. K. Ibrahim, and E. E. D. A. El Zahab, "A dynamic economic emission dispatch considering wind power uncertainty incorporating energy storage system and demand side management", Renewable Energy, vol. 96: Pergamon, pp. 800-811, 2016. AbstractWebsite

Reducing carbon emissions is an important goal for the whole world; a high penetration of wind energy can help in reducing emissions. However, great increase in wind energy usage raises some issues concerning its variability and stochastic nature. These issues increase the importance of studying methods of wind energy representation, and in the same time studying the effect of using some flexible resources in decreasing those issues. This paper proposes a dynamic economic emission dispatch (DEED) model incorporating high wind penetration considering its intermittency and uncertainty. Energy storage system (ESS) and demand side management (DSM) are implemented in order to study their effect on the cost, emission, and wind energy utilization. The GAMS software has been utilized to solve this DEED problem. The achieved results show the importance of using ESS and DSM in decreasing both cost and emission, and increasing the wind energy utilization.

Abo-Hamad, G. M., D. K. Ibrahim, E. A. M. Zahab, and A. F. Zobaa, "Dynamic Quadrilateral Characteristic-Based Distance Relays for Transmission Lines Equipped with TCSC", Energies , vol. 14, issue 21, pp. Article 7074, 2021. Abstract

A two-fold adaptive dynamic quadrilateral relay is developed in this research for protecting
Thyristor-Controlled Series Compensator (TCSC)-compensated transmission lines (TLs). By
investigating a new tilt angle and modifying the Takagi method to recognize the fault zone identifier,
the proposed relay adapts its reactive reach and resistive reach separately and independently. The
investigated tilt angle and identified fault zone use the TCSC reactance to compensate its effect
on the TL parameters and system homogeneity. Excessive tests are simulated by MATLAB on the
non-homogenous network, IEEE-9 bus system and further tests are carried out on IEEE-39 bus
system in order to generalize and validate the efficiency of the proposed approach. The designed
trip boundaries are able to detect wide range of resistive faults under all TCSC modes of operations.
The proposed approach is easy to implement as there no need for data synchronization or a high
level of computation and filtration. Moreover, the proposed adaptive dynamic relay can be applied
for non-homogeneity systems and short as well as long TLs which are either TCSC-compensated or
-uncompensated TLs.

Ibrahim, D. K., A. Ibrahim, and I. Hussein Ammar, "Dynamic Voltage Restorer for Deep Voltage Sags and Harmonics Mitigation in Industrial Plant with Sensitive Loads", 16th International Middle East Power Systems Conference, MEPCON 2014, 2014. Abstract

Dynamic Voltage Restorer (DVR) is a fast, flexible and efficient solution for voltage sag problem. It is a power electronic based device that used to compensate voltage sags and harmonics. The DVR has different system topologies for compensation by using battery as an energy storage unit or by using shunt and series converters. In this paper, the DC-DC boost converter is used to connect between shunt and series converters, which allows the DVR to compensate deep sags for long durations. A real case study of Egyptian industrial plant includes a lamp factory as a sensitive load is modeled and simulated using MATLAB/SIMULINK environment to test the effectiveness of using different system topologies of DVR: a battery, shunt and series converters, and finally shunt and series converters with boost converter. Satisfactory performance is achieved using the topology of using shunt and series converters with boost converter for compensating deep voltage sags and harmonics. The financial assessment of using DVR is also investigated.

E
Anwar, Y. A., M. A. R. Shafei, and D. K. Ibrahim, "An economic analysis of rooftop solar power plant and energy auditing for commercial building in Egypt", Smart Grid (SASG), 2017 Saudi Arabia: IEEE, pp. 1-6, 2017. Abstract
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Ahmed, M. A., D. K. Ibrahim, and M. Gilany, "Electric Spring Technology in Small Scale Residential Microgrid", 21st International Middle East Power Systems Conference, MEPCON, Tanta University, Egypt, December 17-19, 2019. Abstract

Energy communities worldwide and in Egypt specifically encourage the household customers toward the renewable energy investment by utilizing grid-connected renewable generators (i.e. PV and wind turbines). Grid stability and power quality become the major concerns for the grid operators as they are too much affected during the increasing penetration of distributed renewable generators and also the growth of non-linear loads at end users. Electric spring (ES) technology is recently applied as distributed voltage controllers intended to stabilize the electrical grid in the presence of the distributed generators and the non-linear loads of the consumers. Consumers' satisfaction towards the grid stability is very essential as most of the household applications include sensitive loads that require a clean power with definite voltage value. This paper analyzes and verifies the electric spring technology in a household application with a renewable energy investment through a grid-connected PV panel, while a standby diesel generator operates in case of utility failure. The proportional-integral (PI) controller of ES has been successfully optimized using a genetic algorithm. A developed MATLAB/SIMULINK model is tested under a real household loading curve, typical PV generation profile in sunny/cloudy days, dynamic response of the standby diesel generator, and the utility disturbances (i.e. voltage decrease, increase, and fluctuation). For all aforementioned tested disturbances, the ES has succeeded to stabilize the voltage for the household sensitive appliances (e.g. computers, TV, washing machine, etc.).

fatma elzahraa magdy, D. K. Ibrahim, and W. Sabry, "Energy management of virtual power plants dependent on electro-economical model", Ain Shams Engineering Journal, vol. 11, issue 3, pp. 643-649, 2020. Abstract

From about two decades passed, a new expression was proposed for the first time: ‘‘Virtual Power Plants (VPPs)”. At this moment, a question was asked about if the VPPs can contribute as a trustworthy and environmentally oriented energy supply, or not? From this instant, over two hundred articles was presented for the management and optimal utilization of such a system, reliability and adaptation of VPP with the network connected to, retail and wholesale markets . . . etc. Most or approximately all articles intended with VPPs focused on studying VPPs from economical point of view only and did not studied the electrical and energy performance of VPPs. This paper represents a novel combined model for economical and electrical performances together of a generic VPP (GVPP); the electro-economical model (EEM). Two main targets are required from the proposed GVPP EEM: best performance and active network energy management of this GVPP. Also, a proposal for the first real case study in Egypt is taken under consideration: Siwa Oasis, Egypt. Siwa Oasis proposed VPP is modeled also with EEM. EEM for these two cases (GVPP and Siwa Oasis VPP) are simulated to obtain best performance and active network energy management for these VPPs. All data and results are stated and discussed.

Afifi, M. K., H. M. Sharaf, M. M. Sayed, and D. K. Ibrahim, "Enhanced Two-Fault Point Multi-Objective Coordination Scheme for Directional Overcurrent Relays in Meshed Distribution", ", 21st International Middle East Power Systems Conference, MEPCON , Tanta University, Egypt, December 17-19, 2019. Abstract

in this paper, an enhanced directional overcurrent relays (DOCRs) coordination scheme is introduced. The proposed scheme considers the fault severity by applying weighting factors, calculated based on system fault currents at different locations in each relay zone of protection. This enhanced coordination reduces the operating time of the relays for severe fault currents avoiding the greater thermal and mechanical stresses that reduce equipment lifetime. The DOCRs coordination problem is formulated as a multi-objective optimization problem to accomplish better results than the single-objective methodology with respect to relays selectivity and speed. DOCRs coordination problem is solved using Goal Attainment method in MATLAB Optimization Toolbox. A two-fault point coordination scheme is applied to IEEE 14 bus system for both the conventional and the proposed scheme. The results are analyzed according to several system performance indices including: the mean of the system’s relays operating times, the maximum primary relay operating time, the maximum backup relay operating time and maximum coordination time interval (CTI) between primary/backup pairs. The achieved results indicated that the proposed scheme considering the severity weighting factors has reduced the mean operating time of relays especially for the relays with faults with high severity. It means more reliable, faster protection system with less thermal and mechanical stresses for system equipment.

Abdelbadea, M., T. A. Boghdady, and D. K. Ibrahim, "Enhancing active radial distribution networks by optimal sizing and placement of DGs using modified Crow Search Algorithm", Indonesian Journal of Electrical Engineering and Computer Science, vol. 16, issue 3, pp. 1179-1188, 2019. Abstract

Incorporating many Distributed Generators (DGs) technologies in power system networks has grown rapidly in recent years. Distributed generation (DG) plays a key role in reducing power loss and enhancing the voltage profile in radial distribution networks. However, inappropriate DGs site or size may cut network efficiency; moreover, injecting harmonics is one of the integration concerns of inverter-based DGs. Two-procedure based approach is introduced in this paper. The first procedure solves the DGs siting and sizing problem, as a multi-objective one by improving the voltage profile of the whole distribution network and also reducing its power loss. A weighted sum method is presented to create the Pareto optimal front in this procedure and get the compromised solution by applying a novel metaheuristic optimizer, named Crow Search Algorithm (CSA). A modification on CSA is also proposed and applied to improve its performance. The achieved solution for inverter-based DGs placement and size is checked in the second procedure to make sure the accepted voltage THD at all buses by implementing detailed simulation for the tested system using Matlab/Simulink. The proposed approach has been tested on IEEE 33-bus radial distribution system with photovoltaic DGs. To confirm the superiority of the modified CSA algorithm in terms of quality of solution, its achieved results are compared with the results offered by the original CSA algorithm and published results of some other nature-inspired algorithms.

Ibrahim, D. K., M. M. Abdel Aziz, N. M. Abdel Fattah, and A. Ramadan, "Enhancing Backup Protection Of Series Compensated Lines Using Wavelet Packet Transform", Proceedings of the 15th International Middle East Power Systems Conference, MEPCON 2012; Alexandria, Egypt, December, 23-25, 2012., 2012. Abstract

Series compensated lines present challenges for directional, distance, and differential elements because the transient response of the series capacitor is not readily predictable. This paper presents a directional overcurrent relay that used as a backup protection for distance relays in series compensated lines. Wavelet Packet Transform (WPT) technique is used for proper fundamental RMS value calculating of current and voltage signals since it can preserve both time and frequency information with high resolution by decomposing a waveform into uniform frequency bands, and measuring individual harmonic components. The proposed scheme demonstrates its feasible performance in detecting nonlinear high impedance faults with low voltage and current variation for maximum trip time required of 2 cycles. In addition, the proposed scheme examines the load current continuously and changes the relay pick up value adaptively. Characteristics of the proposed scheme are fully analyzed by extensive ATP/EMTP simulation studies that clearly reveal that the proposed scheme has an efficient performance insensitive of the variation of different fault conditions that may occur in double ended transmission lines with series capacitors at the middle of the line.

MOHAMED, A. H. M. E. D. A. B. D. E. L. R. A. H. M. A. N., H. Mohamed Sharaf, and D. K. Ibrahim, "Enhancing Distance Protection of Long Transmission Lines Compensated with TCSC and Connected With Wind Power", IEEE Access, vol. 9, pp. 46717 - 46730, 2021. Abstract

Thyristor controlled series compensation (TCSC) is widely used in long transmission lines to mainly improve power transfer capability. However, TCSC produces complicated impedance that negatively affects distance protection operation. The wind energy generation system produces additional complexity to the distance protection performance due to the variation of wind speed and fault current level. This paper proposes an integrated scheme to change adaptively the settings of the Mho distance protection by shifting the relay characteristics considering the bad impacts of TCSC, wind power and fault resistance. The proposed scheme achieves its main stages starting from fault detection, until relay tripping decision procedure including online estimation for preliminary fault location, impedance of TCSC and fault resistance using limited communication requirements. By extensive MATLAB simulations, the performance of the proposed scheme is examined compared with the conventional Mho relays under different fault locations, fault inception angle, fault resistance, different wind power penetration, different wind speeds and different TCSC ring angles. The achieved results ensured that the proposed scheme improves significantly Mho distance relay operation and avoids under-reaching and over-reaching problems irrespective of the large shunt capacitance along the transmission line, and also without identifying the parameters of TCSC such as the capacitance, the inductance or the ring angle.

El-Sayed, L. M. A., D. K. Ibrahim, M. I. gilany, and A. ' F. El'Gharably, "Enhancing Distance Relay Performance Using Wide-Area Protection for Detecting Symmetrical/Unsymmetrical Faults during Power Swings", Alexandria Engineering Journal, vol. 61, issue 9, pp. 6869-6886, 2022. Abstract

The distance protection in transmission networks is vulnerable to malfunction during a power swing. Distance relays have a power swing blocking (PSB) function that prevents the relay from operating during a power swing. However, during a power swing, the relay will be able to identify and clear any fault. This paper offers a scheme for detecting symmetrical/unsymmetrical faults through power swing by estimating the maximum rate of change of a (DI- DV) ellipse circumference.
The ellipse circumference of each phase is constructed at each power frequency cycle to consistently tracking the distinction in the measured current and voltage differences between the line’s two ends. The main feature of the suggested work compared to previous works is the ability to detect numerous high impedance faults (HIFs) during single mode (slow/fast) power swing or multi-mode power swing in addition to the opportunity to detect faults during asymmetrical power swing. The suggested scheme is tested in a two-area, four-machine power system and tested also in the standard three-machine, nine-bus system using ATP software. The results reveal that the improved protective scheme performs well in fault conditions with and without power swing, and they confirm the scheme’s suitability for interconnected networks.

Shafei, M. A. R., A. N. A. Alzaher, and D. K. Ibrahim, "Enhancing load frequency control of multi-area multi-sources power system with renewable units and including nonlinearities", Indonesian Journal of Electrical Engineering and Computer Science, vol. 19, issue 1, pp. 109-118, 2020. Abstract

The foremost aims of the Load Frequency Control (LFC) is to maintain the frequency at nominal value and minimize the unscheduled tie line power flow between different control areas. The penetration of renewable energy sources into the grid is a recent challenge to the power system operators due to their different modelling rather than conventional units. In this paper, enhancing load frequency control of multi-area multi-sources power system with nonlinearities including renewable units is proposed using a new application of proportional–integral–derivative controller with proportional controller in the inner feedback loop, which is called as PID-P controller. To investigate the performance of the proposed controller, a thermal with reheater, hydro, wind and diesel power generation units with physical constraints such as governor dead band, generation rate constraint, time delay and boiler dynamics are considered. The proposed controller parameters are optimized using different heuristic optimization techniques such: Linearized Biogeography-Based Optimization technique, Biogeography-Based Optimization technique and Genetic Algorithm. The ability of the system to handle the large variation in load conditions, time delay, participation factors, and system parameters has been verified comprehensively.

Magdy, M., M. Elshahed, and D. K. Ibrahim, "Enhancing PV Hosting Capacity Using Smart Inverters and Time of Use Tariffs", Iranian Journal of Science and Technology, Transactions of Electrical Engineering, vol. 45, issue 3, pp. 905–920, 2021. Abstract

Optimizing the Photovoltaic (PV) hosting capacity (HC) considering the irradiance’s variability properly and the load during the day represents a critical matter. Typically, the high PV HC results in overvoltage and high voltage fluctuations at the point of common coupling (PCC) with the utility. In this paper, a new algorithm is proposed for enhancing PV HC by considering the smart inverter functions to overcome key PCC issues. The Volt-Var and dynamic reactive current functions of the smart inverter are suggested to increase the PV HC. Furthermore, the time of use tariff is utilized for mitigating the duck curve issue at the utility by reducing the peak to valley difference of the substation net load curve. Quasi-static timeseries simulations are performed using the OpenDSS program to prove the effectiveness of the proposed algorithm. The proposed algorithm is validated by extensive numerical analysis on the standard IEEE 123 node test feeder. Deduced outcomes are very encouraging in mitigating the overvoltage, reducing the energy losses, limiting the considerable number of on-load tap changes, and alleviating the high voltage fluctuations.

Khalil, E. A., T. a. Boghdady, M. H. Alham, and D. K. Ibrahim, "Enhancing the Conventional Controllers for Load Frequency Control of Isolated Microgrids Using Proposed Multi-Objective Formulation Via Artificial Rabbits Optimization Algorithm", IEEE Access, vol. 11, pp. 3472- 3493, 2023. AbstractWebsite

Isolated microgrids (IMGs) power remote areas. However, IMG may lower the frequency stability and increase frequency excursions with low system inertia. Load frequency management ensures system stability. Thus, the paper proposes a novel multi-objective tuning strategy to improve IMG's load frequency control (LFC) and take the microgrid controller's control signals into account. Diesel engine generator, fuel cell, battery energy storage system, and renewable energy sources (RESs) like photovoltaic and wind systems make up the IMG. Conventional controllers such as proportional-integral (PI) and proportional integral derivative (PID) are classically tuned based on the standard error criteria as a traditional single-objective tuning approach. Due to the low inertia of the system and the stochastic nature of RES, they cannot act as required under different operating scenarios. Therefore, the PI and PID controllers are tuned using the proposed multi-objective-based tuning approach to reduce the frequency deviations. In addition, anti-windup is applied to the enhanced classic controllers to keep them distant from the nonlinear zone and beyond the source's physical constraints. The proposed tuning process also considers the maximum practical generation rates for different sources. The recent Artificial Rabbits Optimization (ARO) algorithm is applied to simultaneously adjust the controller parameters for several controlled sources in IMG. Extensive simulations in MATLAB and Simulink confirm the effectiveness of the proposed approach to keep the system stable even when facing high levels of disturbances. In addition, accomplishing sensitivity analysis, severe +-25% changes to the system's parameters guarantee that the proposed tuning strategy keeps the system stable.

Fayez, K. M., M. A. R. Shafei, and D. K. Ibrahim, "Enhancing Thermal Performance and Lifetime Cycles of Li-ion Battery in Electric Vehicles", ”, International Journal of Renewable Energy Research, vol. 11, issue 3, pp. 1166-1177, 2021. Abstract

Hybrid energy storage system has essential priority in Electric Vehicle applications. Therefore, the design of an appropriate power sharing algorithm among energy storage components is necessary to improve battery thermal performance and provide extra extension of battery lifetime cycles. This paper presents an analytical study on the effect of using wavelet decomposition-based power sharing algorithm to force the high frequency component to be fed by the supercapacitor and accordingly reduces the thermal stress on the battery. The proposed approach was investigated by applying it on electric vehicle model in ADVISOR Tool/MATLAB using different driving profiles such as Urban Dynamometer Driving Schedule profile, Highway Fuel Economy Test, New York City Cycle, Los Angeles 1992 and new European driving cycle. The results declare that by using proposed power sharing algorithm, the working temperature of lithium battery decreases significantly while battery lifetime cycles increase, apparently. For urban dynamometer driving schedule, the operating temperature of lithium battery is improved much at maximum decomposition levels reaching to only 25.6 °C compared to 35 °C. In addition, the battery lifetime cycles increased from 2213 to 2585 cycles. Neural Networks pattern recognition tool is also applied to classify the driving cycle to the nearest reference cycles chosen to represent the different driving conditions which help to detect the appropriate wavelet decomposition level, achieving better battery thermal performance and battery lifetime cycles.

Al-Barashi, M. M., D. K. Ibrahim, and E. E. - D. A. El-Zahab, "Evaluating Connecting Al-Mukha New Wind Farm to Yemen Power System", International Journal of Electrical Energy, vol. 3, issue 2, pp. 57-67, 2015. AbstractWebsite

This paper presents modeling and impact analysis of Al-Mukha wind farm (MWF) on Yemen power system, which is made of thermal power plants. In this paper, four kinds of major components are modeled: a 60MW wind farm, a transmission network, thermal power plants, and the Yemen power system load. To analyze the impact of the wind power generation to the Yemen power system, simulations are carried out for two case studies by using the DIgSILENT program. The first is the case of grid impact studies: impact on thermal limits, voltage variations, and system stability, in which an aggregated model of the wind farm is used. The other is the dynamic performance of the wind farm by analyzing low-voltage ride through LVRT, harmonics and flicker impact on the basis of the detailed wind farm layout with 30 wind turbines (WTs) arranged in four stands and the external grid of 2175MVA short-circuit capacity. The simulation results show that the loading of most lines and voltage variations are slightly reduced. In addition, there is no harmful effect on the system stability and also the wind farm is capable to ride through the grid fault. Finally, it is shown that the wind farm contributes voltage and current harmonics higher than the permissible limits while the flicker levels are far below any critical values. 

Al-Barashi, M. M., D. K. Ibrahim, and E. E. - D. A. El-Zahab, "Evaluating The Energy System in Yemen", Journal of Electric Engineering, JEE, vol. 16, issue 1, pp. 338-342 (Article 16.1.41), 2016. AbstractWebsite

This paper presents a deep analysis for the energy system in Yemen, which consists of thermal power plants taking into account the strengths and weaknesses of its power system. The investigation results show that Yemen power system suffers lacking of energy efficiency (EE), weak institutional capacity, high losses in the generation, transmission and distribution grids, and currently the disability to invest in renewable energy (RE). Yemen should focus on foundational activities to build institutional capacity and mobilize resources to initiate suitable energy efficiency policies and measures. Yemen should also focus on exploring the opportunities of designing innovative energy systems based on decentralized small-scale power generation. Microgrids could enable power supply to remote areas at lower costs than required by traditional infrastructure.

Abd El-Rahman, A., D. K. Ibrahim, and G. Mahmoud, "Evaluation of Protective Schemes for Grid-Connected Generator-Transformer Units in Egypt", 17th International Middle East Power Systems Conference, MEPCON 2015; Mansoura University, Egypt, December, 15-17, 2015., 2015. Abstract

Synchronous generator in electric power plants –as well as the power transformer - is very important and expensive element so it should be provided with fully protection system to protect it against any abnormal conditions. Failure can occur in a generator or transformer due to different reasons. The protection system must prevent the protected equipment from being affected by external faults in addition to prevent evolving damage in case of internal faults. Repeated breaks of generation power stations in last few years are recorded. Because of their great impact on the Egyptian unity network (500 kV and 220 kV), it is essential to deeply review the efficiency of various existing protection schemes designed for generating stations. Detailed analyses of some of the major and destructive real faults recorded at some stations are carried out. Accordingly, modifications for the power plant protection schemes are recommended.

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Saleh, S. M., and D. K. Ibrahim, "Fault Detection Technique of High Impedance Faults in EHV Transmission Lines Using Combined Wavelet Transform and Prony’s Method", 16th International Middle East Power Systems Conference, MEPCON 2014, 2014. Abstract

High impedance faults (HIFs) are difficult to detect by conventional protection devices such as distance and
overcurrent relays. This paper presents a scheme for high impedance fault detection in extra high voltage transmission line by recognizing the distortion of the voltage waveforms caused by the arcs usually associated with HIFs. The proposed scheme is based on combined wavelet transform and Prony’s method. The discrete wavelet transform (DWT) based analysis, yields three phase voltages in the high
frequency range which are fed to a classifier for pattern recognition and also fed to the Prony’s method for correct discriminating of switching with and without fault cases. The classifier is based on an algorithm that uses a recursive method to sum the absolute values of the high frequency signal generated over one cycle by shifting one sample, while switching cases discrimination is based on Prony’s amplitude changing
with time. Characteristics of the proposed fault detection scheme are analysed by extensive simulation studies that clearly reveal that the proposed scheme can accurately detect HIFs in the EHV transmission lines. Results of extensive simulations using ATP/EMTP on 500 kV Egyptian transmission line clearly reveal that the proposed scheme can accurately detect HIFs in the EHV transmission lines systems as well as its ability to discriminate clearly between HIFs and various switching conditions.

Din, E. S. T. E., M. M. Abdel Aziz, M. Gilany, and D. K. Ibrahim, "Fault location scheme for combined overhead line with underground power cable", Electric power systems research, vol. 76, issue 11: Elsevier, pp. 928-935, 2006. AbstractWebsite

This paper presents a fault location scheme for transmission systems consisting of an overhead line combined with an underground power cable. The algorithm requires phasor measurements data from one end of the transmission line and the synchronized measurements at the most far end of the power cable. Fault location is derived using distributed line model, modal transformation theory and Discrete Fourier Transform. The technique can be used on-line or off-line using the data stored in the digital fault recording apparatuses. The proposed scheme has the ability to locate the fault whether it is in the overhead line or in the underground power cable. In addition to, the proposed scheme gives an accurate estimation of the fault resistance at fault location. Extensive simulation studies carried out using MATLAB show that the proposed scheme provides a high accuracy in fault location under various fault conditions.

Din, E. S. T. E., and D. K. Ibrahim, "A Fault Location Scheme for High Resistance Shunt/Series Faults in Radial Cable Systems", Scientific Bulletin of Faculty of Engineering, Ain Shams University, vol. 41, issue 2: ISSN 1110-1385, pp. 587-612, 2006. Abstract
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Sabra, H., D. K. Ibrahim, and M. Gilany, "Field experience with sympathetic tripping in distribution networks: problems and Solutions", The journal of Engineering, IET, vol. 2018, issue 15, pp. 1181 – 1185, 2018. AbstractWebsite

Sympathetic tripping is a common challenge that affects the proper operation of the earth fault relays in distribution networks. It likely occurs when healthy feeders are exposed to an unnecessary trip operation in response to an actual fault occurring on an adjacent feeder. The sympathetic tripping phenomena of overcurrent and earth fault (EF) relays in the distribution networks and their causes are studied in this paper. Real recorded data of affected healthy feeder(s) for different sympathetic trip scenarios reported from an Egyptian distribution network are extensively analysed. A custom logic protection scheme is proposed to detect the sympathetic tripping phenomena using the existing features of IED relays without any additional cost. In addition to the captured real disturbance records, simulated scenarios of sympathetic tripping are modelled using MODELS language in ATP/EMTP program to evaluate the proposed schemes. The achieved results ensure the suitability of the proposed protection program in order to avoid the unnecessary false sympathetic tripping for both incoming and outgoing feeders.

Shafei, M. A. R., M. A. Tawfik, and D. K. Ibrahim, "Fuzzy control scheme for energy efficiency and demand management in airports using 3D simulator", Indonesian Journal of Electrical Engineering and Computer Science, vol. 20, issue 2, pp. 583-592, 2020. Abstract

As the building sector has the largest share of energy consumption in most countries of the world, this paper focused on the study of one of the most important of the buildings which are the airports. Airports can play a major role in reducing the burden on the electrical grid as they have several factors that make them optimum models for applying energy efficiency strategies. Accordingly, the contribution in this paper is achieved by applying a Fuzzy Logic Control (FLC) scheme to improve the energy efficiency of the Egyptian airports without compromising the comfort level of the occupants and validating the obtained results by the aid of ―DesignBuilder‖ software conducted with the ―EnergyPlus‖ simulator, which is a state-of-the-art 3D simulator tool for checking building energy, carbon, lighting, and comfort performance. The applied 3D simulator evaluates the impacts of implementing the proposed fuzzy control system instead of ON/OFF control schemes or Building Management System (BMS). In this context, case studies were conducted at three different Egyptian airports as a high, medium, and low occupancy level airports respectively to discuss the opportunities and challenges of applying the fuzzy logic scheme in airports according to the occupancy level.

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El Din, E. S. T., D. K. Ibrahim, E. M. Aboul-Zahab, and S. M. Saleh, "High impedance fault detection in EHV series compensated lines using the wavelet transform", Power Systems Conference and Exposition, 2009. PSCE'09. IEEE/PES, Washington, U.S.A., IEEE, pp. 1-10, 2009. Abstract

Coupling capacitive voltage transformers behave as low pass filters which reject the high frequencies associated with voltage signals, so the effect of HIF on voltage signals is neglected. In addition, using series capacitors (SCs) equipped with metal oxide varistors (MOVs) increases the protection relaying problems and complicates the trip decision. This paper presents a high impedance fault detection algorithm for maximum trip time required of 3/4 cycle. The proposed scheme implemented on two different models of HIF in extra high voltage double-ended transmission lines with series capacitors at the middle of the line. The scheme recognizes the distortion of the voltage waveforms caused by the arcs usually associated with HIFs. The discrete wavelet transform (DWT) based analysis, yields three phase voltages in high frequency range which are fed to Clarke’s transformation to produce ground and aerial modes
voltage components for pattern recognition. The classifier is based on an algorithm that uses recursive method to sum the absolute values of high frequency signals generated over one cycle and shifts one sample. Characteristics of the proposed scheme are fully analyzed by extensive ATP/EMTP simulation studies that clearly reveal that the proposed method can accurately detect HIFs in EHV transmission lines and does not affected by different fault conditions such as fault distance and fault inception angle.

Aboul-Zahab, E. M., E. - S. T. Eldin, D. K. Ibrahim, and S. M. Saleh, "High impedance fault detection in mutually coupled double-ended transmission lines using high frequency disturbances", Power System Conference, 2008. MEPCON 2008. 12th International Middle-East: IEEE, pp. 412-419, 2008. Abstract

Coupling Capacitor Voltage Transformer (CCVT) secondary voltages, normally applied to conventional schemes, do not comprise appropriate information for schemes that operate on high frequency fault generated transients. However it is possible to capture the required travelling wave information contained in fault transients using a high frequency tap from a CCVT. This paper presents an ATP/EMTP fault simulations studies based algorithm for half cycle high impedance fault detection. The proposed scheme implemented on two different models of HIF in extra high voltage mutually coupled double-ended transmission lines. The scheme recognizes the distortion of the voltage waveforms caused by the arcs usually associated with HIFs. The high pass filter tap yields three phase voltage in the high frequency range which are fed to Clarke’s transformation to decouple the traveling waves of the mutually coupled lines and produces ground mode and aerial modes voltage components to
the classifier for pattern recognition. The classifier is based on an algorithm that uses recursive method to sum the absolute values of the high frequency signal generated over one cycle and shifting one sample. Characteristics of the proposed fault detection scheme are analyzed by extensive simulation studies that clearly reveal that the proposed method can accurately detect HIFs in the EHV transmission lines within only half a cycle from the instant of fault occurrence. The reliability of the proposed scheme does not affected by different fault conditions such as fault distance and fault inception angle.

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