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Journal Article
Eldin, E. M. T., M. I. Gilany, M. M. Abdel Aziz, and D. K. Ibrahim, "An accurate fault location scheme for connected aged cable lines in double-fed systems", Electrical Engineering, vol. 88, issue 5: Springer, pp. 431-439, 2006. AbstractWebsite

This paper presents an adaptive fault location scheme for aged power cables using synchronized phasor measurements from both ends of the cable. 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 scheme responds very well to any fault insensitive to fault type, fault resistance, fault inception angle and system configuration. The proposed scheme solves the problem of aged cables with the change of the electric parameters. In addition to, it gives an accurate estimation of the fault resistance.

El-Sayed, L. M. A., D. K. Ibrahim, M. I. gilany, and A. ’F. El’Gharably, "An Accurate Technique for Supervising Distance Relays during Power Swing", Indonesian Journal of Electrical Engineering and Computer Science, vol. 21, issue 3, pp. 1279-1290, 2021. AbstractWebsite

Power swing is a power system transient phenomenon that arises due to several reasons including line switching, line outage, sudden increment or decrement in load, faults, etc. Unnecessary tripping during power swing and unnecessary blocking for faults occur during power swing result in distance relay maloperation. Several cascaded outages and major worldwide blackouts have occurred due to maloperation of distance relays. This paper proposes a technique for supervising distance relays during power swing. The proposed
online technique discriminates real faults and power swing accurately. It relies on constructing a locus diagram for the current and voltage differences (ΔI-ΔV) between the two ends of the protected line. The locus is estimated at every power frequency cycle to continuously monitor the state of the line by utilizing the synchrophasor measurements at the sending and receiving ends of the line. The proposed technique is tested for two-area, four-machine power system under faults at different locations of zone-1 and zone-2 regions of distance relays, fault resistances, fault inception angles and slip frequencies using MATLAB software. The simulation results proved the superior improvement of distance relay performance for handling power swing blocking and unblocking actions.

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.

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.

Rashad, B. A. - E., D. K. Ibrahim, M. I. Gilany, and A. ’F. El’Gharably, "Adaptive Single-End Transient-based Scheme for Detection and Location of Open Conductor Faults in HV Transmission Lines", Electric Power Systems Research, vol. 182, issue May 2020, pp. Article 106252, 2020. Abstract

Detection and location of open conductor in transmission systems using single-end data is a challenging task. This paper proposes a novel integrated scheme to detect and locate different types of open conductor faults (OCFs) in HV transmission systems. The proposed scheme unit (PSU) applies Discrete Wavelet Transform (DWT) with single-level decomposition on local current signals to detect OCFs correctly using adaptively estimated threshold values. PSU is also capable of dealing correctly with various normal transient conditions such as load capacitor switching. To ensure quick repair of OCFs, PSU captures the transient voltage surges and applies a fault location scheme using DWT and Clark Transformation to accurately estimate the location of different OCFs types. Extensive ATP simulations are employed to check the PSU performance under various OCFs conditions on a 345 kV, 100 km transmission line. The achieved results confirm the effectiveness, robustness, and reliability of PSU in detecting correctly OCFs as well as the low-impedance faults within only 1.25 cycles. Moreover, the percentage error in estimating OCFs location is less than 1%. PSU has also confirmed its capability to be applied in cascaded lines without any communication or synchronization between PSUs.

Shafei, M. A. R., D. K. Ibrahim, and M. Bahaa, "Application of PSO tuned fuzzy logic controller for LFC of two-area power system with redox flow battery and PV solar park", Ain Shams Engineering Journal, vol. 13, issue 5, pp. Article No. 101710, 2022. Abstract

Nowadays, integrating large scale renewable energy sources, like solar PV parks, raises challenges for Load Frequency Controllers (LFC). The output of PV varies continuously, which requires a robust LFC deals
logically without continuous tuning and parameters optimization. In this paper, a fuzzy logic controller (FLC) is proposed to act as the main LFC instead of the traditional proportional–integral–derivative (PID) controller. The dynamic performance of FLC is enhanced by optimizing its parameters for different cost functions using particle swarm optimization technique (PSO). Another two FLCs will be added to PV system to act as an output controller instead of maximum power point tracker (MPPT) to enhance the overall system performance. To increase system reliability, a fast active power source called redox flow battery (RFB) is added in the proposed model as a frequency stabilizer. RFB can deeply discharge up to 90% with theoretically limitless number of duty cycles and has fast time response for severe load changes. The
importance of these proposed controllers side by side with RFB is to avoid disconnecting solar parks during
heavy cloudy days while preserving on maximizing its output during these periods. The superiority of the proposed FLC is examined by evaluating its performance compared to another control approach called PID-P (PID controller with P controller in the inner feedback loop). Finally, a comprehensive sensitivity analysis is also presented to investigate the controller robustness for extensive changes in power system parameters and loading.

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.

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.

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. 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.

Ibrahim, D. K., G. M. Abo-Hamad, A. E. E. M. Zahab, and A. F. Zobaa, "Comprehensive Analysis of the Impact of the TCSC on Distance Relays in Interconnected Transmission Networks", IEEE Access, vol. 8, pp. 228315 – 228325, 2020. Abstract

This article extensively investigates the calculations of the compensation factor of the thyristor-controlled series compensator (TCSC), which are used to accurately evaluate the negative impacts of the TCSC on the performance of conventional distance relays. To broadly evaluate the distance protection performance, the TCSC was adapted to the IEEE 9-bus system as one of the interconnected transmission networks that are increasingly spreading to improve service reliability, reduce reserve capacity, and enhance system efciency. In addition, IEEE 39-bus system, as a large interconnected system, is also examined to generalize the TCSC impact on different interconnected systems. To determine the precise impact, the impedance of the TCSC was calculated based on its practical design parameters. The impedance of the TCSC was examined as a function of transmission line impedance and ring angle. Both Mho and Quadrilateral distance relays were tested using the MATLAB/Simulink environment for different types of faults, fault locations, fault resistances, and ring angles for capacitive, inductive, and blocking modes of TCSC operation. In addition, distance relay performance was evaluated during power swing phenomenon in the presence of the TCSC. Simulation tests indicated the negative impacts of the TCSC on distance relay operation, which are not limited to over-reach and under-reach in faulty conditions but also to maloperation in dynamic disturbances that cause power swing phenomena on the protected line.

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.

Mostafa, S. A. E. A., D. K. Ibrahim, and E. E. - D. A. El-Zahab, "Directional Overcurrent Relays Coordination Restoration By Reducing Minimum Fault Current Limiter Impedance", Journal of Energy and Power Engineering, vol. 8, pp. 1132–1141, 2014. AbstractWebsite

FCL (fault current limiter) is used to solve relays miscoordination problem arises from DG (distributed generation) installation. In most published researches, different optimization methods are developed to obtain optimal relay settings to achieve coordination in case of not installing DG, then depending on the achieved optimal obtained relay settings, FCL impedance is deduced to ensure relays coordination restoration in case of installing DG. Based on original optimal relay settings, obtained FCL impedance is not the minimum one required to achieve relay coordination. The contribution of this paper is the generation of multi sets of original relay settings that increase the possibility of finding FCL impedance of minimum value which is lower than the calculated value based on original optimal relay settings. The proposed method achieves better economic target by reducing FCL impedance. The proposed approach is implemented and tested on IEEE-39 bus test system.

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.

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.

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.

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.