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Conference Proceedings
Ibrahim, D. K., M. M. Abdel Aziz, N. M. Abdel Fattah, and A. Ramadan, "Detection and Location of Distribution Systems Faults using Wavelet Packet Transform Based Overcurrent Relay", Proceedings of the 8th International Conference on Electrical Engineering, ICEENG Conference, Military Technical College, Cairo, Egypt, 29-31 May, 2012., Egypt, 2012. Abstract

This paper presents a scheme to increase the sensitivity of overcurrent protection. The proposed scheme applies wavelet packet transform, since it can preserve both time and frequency information with high resolution. The proposed scheme demonstrates its feasible performance in detecting short circuit faults, calculating fault location with moderate accuracy and detecting nonlinear high impedance faults. In addition, the proposed scheme examines the load current continuously and has the ability of changing the relay pick up value adaptively. The examined tested cases include different internal short circuit fault conditions, different nonlinear high impedance faults, and non fault situations such as normal load changing. The obtained results indicate that the developed scheme is fast, robust, reliable and suitable for power distribution systems.

Mohamed Sharaf, H., H. H. Zeineldin, D. K. Ibrahim, and E. E. L. - D. A. EL-Zahab, "Directional Inverse Time Overcurrent Relay for Meshed Distribution Systems with Distributed Generation with Additional Continuous Relay Settings", 12th International Conference on Developments in Power System Protection, 31 March - 3 April 2014 Copenhagen., Copenhagen, IET, 2014. Abstract

Coordination between inverse time overcurrent relays within meshed systems are achieved by adjusting two relay settings; pick up current and time multiplier settings. The operating time of these relays is also a function of two additional constants; one represents the constant for relay characteristics and the other one represents the inverse time type. For typical relays, each of these two constants has four definite values and choosing between them indicates the selected relay operating curve: either standard inverse, very inverse, extremely inverse or long time standby earth fault time-current relay characteristics. In this paper, a coordination strategy, that takes advantage of the available capabilities in microprocessor based relays, is proposed by considering the two relay characteristic constants as continuous variable settings that can be adjusted in addition to the conventional pickup current and Time Dial Setting (TDS). The protection coordination problem is formulated as a nonlinear programming problem where the main objective is to minimize the overall time of operation of relays taking into account protection coordination constraints. The proposed approach is applied to the IEEE 14 bus system and is compared with the conventional two setting relay.

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", Proceedings of the 15th International Middle East Power Systems Conference, MEPCON 2012; Alexandria, Egypt, December, 23-25, 2012, 2012. Abstract
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Yousef, W. H., D. K. Ibrahim, and E. Abo El-Zahab, "Discrimination of Internal Faults and Inrush Currents For Large Modern Power Transformer", 14th International Middle East Power Systems Conference (MEPCON’10), Cairo University, Egypt, 2010. Abstract

This paper presents a differential protection approach for large high quality power transformers that have
low inrush currents of about 3.14 times rated currents. Such transformers have low second harmonic level, which results in conventional differential protection malfunction. A scheme for internal faults and inrush currents discrimination based on both discrete Fourier transform DFT and discrete Wavelet Transform
DWT is proposed. The proposed method has been designed based on the percentage of the sum of wavelet transform coefficients D1 and fundamental differential current (based on a 1 kHz sampling
rate). It has been tested by extensive EMTP/ ATP simulations for different faults and switching conditions on El Tebbin Power Plant 220/21 kV generator/power transformer. It is proved that it has a high capability for discrimination even in the case of inrush with low second harmonic content and internal fault currents with high second harmonic component. All tests proved that the proposed scheme is reliable, accurate, and fast.

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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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.

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.

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.

Gilany, M. I., M. M. Abdel Aziz, and D. K. Ibrahim, "High Impedance Fault Detection Using a Communication based Element", 2nd IASTED International Conference Power and Energy Systems EuroPES ,Crete, Greece , 25-28 June, 2002, Creete, Greece, pp. 661-664, 2002. Abstract

Faults on distribution circuits are normally detected by simple overcurrent relays. Faults through high impedance (HIF) such as dry earth don’t have sufficient current to operate overcurrent relays. In some cases, fault current is less than the normal current. The broken cables laid on the soil, can be left energized for long periods of time. This presents a serious hazard to the general public with risks of electric shock, fire, etc. This paper describes a new scheme for high impedance fault detection using the concept of digital communications. The proposed model posses a high capability of distinguishing the HIF from normal switching conditions.

Eldin, E. S. T., D. K. Ibrahim, E. M. Aboul-Zahab, and S. M. Saleh, "High impedance faults detection in EHV transmission lines using the wavelet transforms", Power Engineering Society General Meeting, 2007. IEEE: IEEE, pp. 1-7, 2007. Abstract

High impedance faults (HIFs) are difficult to be detected by overcurrent protection relays. This paper presents an ATP/EMTP fault simulations studies based algorithm for high impedance fault detection in extra high voltage transmission line. The scheme recognizes the distortion of the voltage waveforms caused by the arcs usually associated with HIF. The discrete wavelet transform (DWT) based analysis, yields three phase voltage in the high frequency range which are fed to a 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. A HIF model of distribution is modified for EHV transmission lines. 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.

Ibrahim, D. K., E. - S. T. Eldin, E. M. Aboul-Zahab, and S. M. Saleh, "High-impedance fault detection in EHV transmission lines", Power System Conference, 2008. MEPCON 2008. 12th International Middle-East: IEEE, pp. 192-199, 2008. Abstract

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Ibrahim, D. K., A. F. Zobaa, E. Abo El-Zahab, and G. M. Abo-Hamad, "A Hybird Algorithm for Blocking Power Swings", Proceedings of the 7th International Conference on Electrical Engineering, (ICEENG) Conference, 25-27 May, Cairo, Egypt, 2010., 2010. Abstract
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Ibrahim, D. K., M. E. Rezk, A. El-Zahab, and E. El-Din, "Improving distance protection performance at zone1 using new adaptive tripping time scheme", Energy Conference (ENERGYCON), 2014 IEEE International: IEEE, pp. 528-535, 2014. Abstract

This paper presents a new adaptive tripping time scheme which provides high speed distance relay operation under fault conditions near the relay point and provides high secured detection for the faults occurred at the end of the protected transmission line with tripping time less than one power cycle. The proposed scheme automatically controls the data window length to adaptively speed up its response under various fault conditions. The advanced feature of this scheme provides capability for fast tripping decisions with secure operation. The proposed scheme possesses the advantage of removing decaying DC offset component in the current signals according to the length of data window, and compensates the capacitive current during the calculation of the fault impedance. Extensive simulations show that the proposed scheme provides better protection performance compared with the conventional schemes of the fixed data window.

Gouda, O. E., D. K. Ibrahim, D. H. Helmi, D. M. Khalifa, and G. M. Amer, "Improving Transmission Line Performance using Transient Based Adaptive SPAR", 14th International Middle East Power Systems Conference (MEPCON’10), Cairo University, Egypt, 2010. Abstract

Adaptive SPAR offers many advantages over conventional techniques. In the case of transient faults, the arcing extinction time can be accurately determined and in the case of a permanent fault, breaker reclosure can be avoided. This paper describes, in some detail, the design of a new Adaptive SPAR technique that extracts high frequencies transients, from the CVT. The main case of study in this paper is the High Dam / Nagh Hamady, Nagh Hamady /Assuit 500 kV double circuit transmission system in the Egyptian network. Fault scenario cases representing different fault locations, inception angles, actual representation to secondary arc characteristics, and with/without shunt reactor existence were extracted from simulation work, and then verified through real field records in that system. The outcome of this study indicates that the proposed technique can be used as an effective means of achieving an adaptive single pole auto reclosure scheme.

Ibrahim, A. N. A. A., M. A. R. Shafei, and D. K. Ibrahim, "Linearized biogeography based optimization tuned PID-P controller for load frequency control of interconnected power system", Power Systems Conference (MEPCON), 2017 Nineteenth International Middle East: IEEE, pp. 1081-1087, 2017. Abstract
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Saleh, S. M., E. M. Aboul-Zahab, E. Tag Eldin, D. K. Ibrahim, and M. I. Gilany, "Neural network-based technique used for recovery the CCVT primary signal", Power & Energy Society General Meeting, 2009. PES'09. IEEE: IEEE, pp. 1-7, 2009. Abstract

The coupling capacitor voltage transformers transient response during faults can cause protective relay mal-operation or even prevent tripping. This paper presents the CCVT transient response errors and the use of artificial neural network (ANN) to correct the CCVT secondary waveform distortion. In this paper, an ANN program is developed to recover the primary voltage from the distorted secondary voltage. The ANN is trained to achieve the inverse transfer function of the coupling capacitor voltage transformer (CCVT), which provides a good estimate of the true primary voltage from the distorted secondary voltage. The neural network is developed and trained using MATLAB simulations. The accuracy of the simulation program is
confirmed by comparison of its response with that of the target value from the simulation data.

Saleh, S. M., and D. K. Ibrahim, "Non-linear high impedance earth faults locator for series compensated transmission lines", Power Systems Conference (MEPCON), 2017 Nineteenth International Middle East: IEEE, pp. 108-113, 2017. Abstract
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Kamal Youssef, H., D. K. Ibrahim, and A. M. Abd El Fattah, "Optimal Allocation of SVC to Enhance Voltage Stability of Power Systems", Proceedings of the 8th International Conference on Electrical Engineering, ICEENG Conference, Military Technical College, Cairo, Egypt, 29-31 May, 2012, 2012. Abstract

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

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

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

Soliman, A. A. R. A. A., M. M. Sayed, and D. K. Ibrahim, "Optimized hybrid microgrid of gas generators-wind farm using crow search algorithm", Proceedings of the 2017 Saudi Arabia Smart Grid (SASG), 12-14 Dec. 2017, Jeddah, Saudi Arabia, 2017. Abstract
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Din, E. S. T. E., M. Gilany, M. M. Abdel Aziz, and D. K. Ibrahim, "An PMU double ended fault location scheme for aged power cables", Power Engineering Society General Meeting, 2005. IEEE: IEEE, pp. 80-86, 2005. Abstract

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

Gilany, M. I., E. M. T. Eldin, M. M. Abdel Aziz, and D. K. Ibrahim, "A pmu-based fault location scheme for combined overhead line with underground power cable", 3rd IEE International Conference on Reliability of Transmission and Distribution Networks (RTDN 2005): IET Digital Library, pp. 255-260, 2005. Abstract
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El-Sonbaty, A. E. - S., H. K. M. Yonssef, and D. K. Ibrahim, "A proposed particle swarm optimization technique for solving non-linear economic dispatch problem", Power Systems Conference, 2006. MEPCON 2006. Eleventh International Middle East, vol. 2, El-Minia, Egypt, IEEE, pp. 606-611, 2006. Abstract

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

Dawoud, M. A., D. K. Ibrahim, and M. Gilany, "Restoring recloser-fuse coordination in radial distribution networks with distributed generation", Power Systems Conference (MEPCON), 2017 Nineteenth International Middle East: IEEE, pp. 170-175, 2017. Abstract
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