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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.

Abdel Aziz, M. M., A. F. Zobaa, D. K. Ibrahim, and M. M. Awad, "Transmission lines differential protection based on the energy conservation law", Electric Power Systems Research, vol. 78, issue 11: Elsevier, pp. 1865-1872, 2008. AbstractWebsite

This paper proposes a differential protection scheme for transmission lines using the energy conservation law. The real power signals at both ends (sending and receiving) of the line are compared with a prespecified value, if the resultant is more than this value, an internal fault is indicated in the transmission line zone. The proposed technique is evaluated using PSCAD/EMTDC program configurated to model the effect of faults on typical 500 kV transmission line. Extensive simulation studies show that this protection scheme has the ability to discriminate internal faults fast and accurately, and is more reliable than conventional biased differential protection scheme, and suitable for all types of lines. Details of the proposed relay design are given in the paper; also results of some performance studies are given.

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.

Abdel-Aziz, M. M., M. I. gilany, D. K. Ibrahim, and A. F. Abdel-Rheem, "Islanding Detection Using Rate of Change of Zero Sequence of Second Harmonic Voltage", International Journal Of Renewable Energy Research, vol. 10, issue 2, pp. 1514-1524, 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.

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.

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.

Abo-Hamad, G. M., D. K. Ibrahim, E. A. M. Zahab, and A. F. Zobaa, "Adaptive Mho Distance Protection for Interconnected Transmission Lines Compensated with Thyristor Controlled Series Capacitor", Energies , vol. 14, issue 9, pp. Article 2477, 2021. Abstract

This paper proposes an adaptive dynamic Mho distance relay based on a phase comparator scheme for protecting interconnected transmission networks compensated with a Thyristor Controlled Series Capacitor (TCSC). The proposed relay uses an impedance index factor to initiate the fault detection subroutine. The RMS of the positive sequence current of the faulted loop and the TCSC terminal current are compared for TCSC zone identification. A phase comparator for ground and phase distance elements is proposed, relying on the positive sequence voltage as a polarized memory quantity, while the operating and polarizing quantities are developed using estimated TCSC impedance to mitigate its negative impact. The proposed scheme is easy in implementation and independent on synchronized data transfer, as minimum communication requirements are needed. To evaluate the performance of the proposed scheme, extensive simulation studies were carried out on an IEEE9 bus system compensated with TCSC for different firing angles covering four modes of TCSC operations, different fault types, and fault locations. In addition, an IEEE-39 bus network, as a large interconnected system, is tested for validation purposes. The achieved results designate the precision of the proposed scheme. Moreover, the results indicate its effectiveness for fault resistance tolerance, close-in three phase faults, and stable power swing phenomenon compared with conventional relays.

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.

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.

Afifi, M. K., H. M. Sharaf, M. M. Sayed, and D. K. Ibrahim, "Comparative Study between Single-Objective and Multi-Objective Optimization Approaches for Directional Overcurrent Relays Coordination Considering Different Fault Locations", 13th IEEE PES PowerTech Conference, Milano, Italy, 23-27 June 2019. Abstract

In this paper, a comparative study of single-objective and multi-objective optimization approaches for directional overcurrent relays (DOCRs) coordination is presented. Singleobjective optimization approach is investigated using two methods; the fmincon function which is the gradient-based method, while the second method is the Genetic Algorithm which is a meta-heuristic technique. Multi-objective optimization approach is investigated using fmincon function and Goal Attainment method. All the methods are available in the MATLAB Optimization Toolbox. Different fault locations on the meshed power distribution network of the IEEE 14 bus system are considered for the investigated methods. The results of singleobjective and multi-objective approaches are compared regarding total relays operating times, mean fault clearing time, maximum primary and backup relays operating time and maximum coordination time interval. The results show that using the multi-objective optimization approach in solving the DOCRs coordination problem achieved less total relays operating time and coordination time intervals which ensure faster fault clearing.

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.).

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.

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. 

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.

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.

Alham, M. H., M. F. Gad, and D. K. Ibrahim, "Applying Marine Predators Algorithm for Optimizing the Layout of Wind Turbines", International Journal of Renewable Energy Research, vol. 13, issue 2, pp. 730-740, 2023. AbstractWebsite

The extracted power from wind is clean, plentiful, and completely renewable. All over the world, researchers keep looking for the best layouts of wind parks to maximize captured energy. To design wind farms suitably, forecast their performance, and understand the strain loads of wind turbines, there is a persistent need to catch a perfect wake model. Wind turbine wakes are one of the most vital factors in the meteorology of wind power due to reducing the power production and the necessity to raise the downstream capacity of wind turbines. This study is divided into two main aspects: firstly, enhancing the optimal layout for the wind turbines at a farm using Marine Predators Algorithm (MPA). The Jensen wake model is applied to get the extracted power for each turbine, which is one of the mutual analytic models used to reach the optimized layout. By comparing the performance of the proposed algorithm with the previous studies achieved by several techniques, the obtained results revealed that the MPA achieves promising results. Secondly, the proposed algorithm is applied for four sites in Egypt as the fraction of occurrence for the selected locations has been adequately calculated using wind speed over five years.

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.

Ali, H. A. E. ‑S., M. H. Alham, and D. K. Ibrahim, "Big data resolving using Apache Spark for load forecasting and demand response in smart grid: a case study of Low Carbon London Project", Journal of Big Data, vol. 11, issue 1, pp. Article no. 59, 2024. Abstract

Using recent information and communication technologies for monitoring and management initiates a revolution in the smart grid. These technologies generate massive data that can only be processed using big data tools. This paper emphasizes the role of big data in resolving load forecasting, renewable energy sources integration,
and demand response as significant aspects of smart grids. Meters data from the Low Carbon London Project is investigated as a case study. Because of the immense stream of meters’ readings and exogenous data added to load forecasting models, addressing the problem is in the context of big data. Descriptive analytics are developed using Spark SQL to get insights regarding household energy consumption. Spark MLlib is utilized for predictive analytics by building scalable machine learning models accommodating meters’ data streams. Multivariate polynomial regression and decision tree models are preferred here based on the big data point of view and the literature that ensures they are accurate and interpretable. The results confirmed the descriptive
analytics and data visualization capabilities to provide valuable insights, guide the feature selection process, and enhance load forecasting models’ accuracy. Accordingly, proper evaluation of demand response programs and integration of renewable energy resources is accomplished using achieved load forecasting results.

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
Atta, M. E. E. - D., D. K. Ibrahim, M. I. gilany, and A. F. Zobaa, "Adaptive Scheme for Detecting Induction Motor Incipient Broken Bar Faults at Various Load and Inertia Conditions", Sensors, vol. 22, issue 1, pp. Article 365, 2022. Abstract

This paper introduces a novel online adaptive protection scheme to detect and diagnose broken bar faults (BBFs) in induction motors during steady-state conditions based on an analytical approach. The proposed scheme can detect precisely adjacent and non-adjacent BBFs in their incipient phases under different inertia, variable loading conditions, and noisy environments. The main idea of the proposed scheme is monitoring the variation in the phase angle of the main sideband frequency components by applying Fast Fourier Transform to only one phase of the stator current. The scheme does not need any predetermined settings but only one of the stator current signals during the commissioning phase. The threshold value is calculated adaptively to discriminate between healthy and faulty cases. Besides, an index is proposed to designate the fault severity. The performance of this scheme is verified using two simulated motors with different designs by applying the finite element method in addition to a real experimental dataset. The results show that the proposed scheme can effectively detect half, one, two, or three broken bars in adjacent/non-adjacent versions and also estimate their severity under different operating conditions and in a noisy environment, with accuracy reaching 100% independently from motor parameters.

Atta, M. E. E. - D., D. K. Ibrahim, and M. Gilany, "Broken Bar Faults Detection under Induction Motor Starting Conditions Using the Optimized Stockwell Transform and Adaptive Time-Frequency Filter", IEEE Transactions on Instrumentation and Measurement, vol. 70, pp. Article 3518110, 2021. Abstract

Most of the published research studies for detecting induction motor broken bar faults (BBFs) use a time–frequency (t − f ) decomposition tool to characterize the fault-related components. However, the identification and the assessment of these components in (t − f ) domain require skilled user or powerful pattern recognition technique. Moreover, a relatively long starting duration is necessary. This article introduces an automated scheme to detect BBFs and distinguish fault severity in induction motors under startup conditions regardless of the user experience and even under short starting duration and in a noisy environment. This scheme is based on the analysis of the starting current using optimized Stockwell transform (ST). An active set algorithm is applied to maximize the energy concentration of the left-side harmonic (LSH) component. Then, an adaptive time–frequency filter is applied to extract the LSH component from the (t − f ) domain, where the energy of the right part of LSH (RLSH) is utilized as an effective index for BBFs detection and for discriminating BBFs severity. Both real experimental data and simulation-based tests on 0.746- and 11-kW motors are used to extensively verify the performance of the proposed scheme. The achieved results have ensured that the proposed scheme can achieve a high accuracy with the minimum data and shortest acquisition time in comparison with some recent methods in the literature.

Atta, M. E. E. - D., D. K. Ibrahim, and M. I. gilany, "Broken Bar Fault Detection and Diagnosis Techniques for Induction Motors and Drives: State of the Art", IEEE Access, vol. 10, pp. 88504 - 88526, 2022. AbstractWebsite

Motors are the higher energy-conversion devices that consume around 40% of the global electrical generated energy. Induction motors are the most popular motor type due to their reliability, robustness, and low cost. Therefore, both condition monitoring and fault diagnosis of induction motor faults have motivated considerable research efforts. In this paper, a comprehensive review of the recent techniques proposed in the literature for broken bar faults detection and diagnosis is presented. This paper mainly investigates the fault detection methods in line-fed and inverter-fed motors proposed after 2015 and published in most relevant journals and conferences. The introduced review has deeply discussed the main features of the reported methods and compared them in many different aspects. Finally, the study has highlighted the main issues and the gaps that require more attention from researchers in this field.

Atta, M. E. E. - D., D. K. Ibrahim, and M. I. gilany, "Detection and Diagnosis of Bearing Faults under Fixed and Time-Varying Speed Conditions Using Persistence Spectrum and Multi-Scale Structural Similarity Index", IEEE Sensors Journal, vol. 22, issue 3, pp. 2637 – 2646, 2022. Abstract

With the widespread use of variable speed drives, a robust scheme that can detect and diagnose bearing faults under fixed and variable speed conditions becomes essential for reliable operation. Unfortunately, most of the reported methods in the literature are dedicated to working under fixed speed and will face challenges under variable speed conditions. Besides, most of them require detailed bearing information that may be unavailable in the real world. Therefore, in this paper, a new scheme is proposed for bearing faults detection and diagnosis under fixed and time varying speed conditions. The proposed scheme is based on the analysis of vibration signals using the persistence spectrum that can provide images rich with health-related features largely independent from rotating speed. Then, the produced image is compared with priorly stored images of the persistence spectrum of a healthy case. This comparison is performed using the multi-scale structural similarity index, which is a robust basis for images comparison without the need for training or expert knowledge. The obtained index is compared against an adaptive threshold for fault detection. Upon detecting a fault, the persistence spectrum image is compared with that of stored different fault types for fault diagnosis. The proposed scheme is extensively validated using three experimental datasets under different speed conditions. The results show that it can detect bearing faults in an earlier stage without the need for bearing specifications or shaft speed. Moreover, it can successfully diagnose bearing faults severity with accuracy reaching 100% with the minimum required data.

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.

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.