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Ibrahim, D. K., E. S. T. E. Din, E. M. Aboul-Zahab, and S. M. Saleh, "Real time evaluation of DWT-based high impedance fault detection in EHV transmission", Electric Power Systems Research, vol. 80, issue 8: Elsevier, pp. 907-914, 2010. AbstractWebsite

It is possible to capture the required travelling wave information contained in fault transients using wavelet transform. This paper presents practical real time testing for the high impedance fault (HIF) detection algorithm based on real time accidents data. The proposed scheme is implemented for HIF detection in extra high voltage transmission lines. 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 this scheme are analyzed by extensive real time studies that clearly reveal that this technique can accurately detect HIFs in the EHV transmission lines within only half a cycle from the instant of fault occurrence. The reliability of this scheme is not affected by different fault conditions such as fault distance and fault inception angle.

Shafei, M. A. R., M. S. Mohamed, A. A. Mansour, and D. K. Ibrahim, "Recharging Portable Devices by Photovoltaic Modules Using Inductive Power Transfer", International Journal on Energy Conversion (IRECON), vol. 9, issue 5, pp. 230-238, 2021. Abstract

Portable devices are part of people’s daily lives, since they provide the capabilities that make life easier. However, they consume much energy that requires continuous charging. Integrating renewable energy sources, especially photovoltaic (PV) modules into wireless charging, has been widely adopted in order to increase availability, flexibility, safety, and robustness. In this paper, a new variable frequency control technique for inductive power transfer (IPT) is proposed in order to overcome the switching frequency limitation and increase the transfer efficiency without increasing the switching frequency. At first, charging power (PV power) is stored in a battery. Then, it is transferred based on inductive coupling when needed. The hardware of the proposed wireless charging system has been carried out for two different configurations. The first one is the single switch using a variable frequency control algorithm, which has achieved 40% efficiency. The other one uses half-wave inverter applying no resonance for two types of core: Nano-crystalline and ferrite. For that configuration, the maximum achieved efficiency has been 80% at zero air gap and 36.91% at the 5 mm air gap by the Nano-crystalline core.

Elhabashy, M. M., H. M. Sharaf, and D. K. Ibrahim, "Reliable protection for static synchronous series compensated double-circuit transmission lines based on positive sequence active power calculations using PMUs", Electric Power Systems Research, vol. 223, issue October 2023, pp. Article no.109695, 2023. AbstractWebsite

Static Synchronous Series Compensator (SSSC) allows dynamic control capabilities of transmitted power. Unfortunately, inserting SSSC in transmission lines (TLs) disturbs impedance-based distance relays as their directionality and reachability are affected by overreaching or underreaching. This paper proposes an approach for protecting double-circuit TLs compensated with SSSC. It relies on the centralized wide-area protection architecture to calculate a proposed driven index: the rate of change of positive sequence active power difference. Phasor measurement units (PMUs) at TL ends estimate voltage and current phasors to calculate the positive sequence active power at TL ends and send them to the system protection center that evaluates the index and gives the trip decision or not. Ensuring the sensitivity, dependability, and security of the approach is essential. So, the overall scheme integrates two other algorithms. One is based on the polarities of the incremental power at both ends to determine whether the fault is internal or external. The other evaluates the phase angle of the integrated impedance to deactivate the power swing-blocking function for fault detection. The scheme's effectiveness is validated comprehensively through extensive simulation tests for fault and system conditions. The results show that the proposed approach is fast, secure, selective, and reliable.

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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Dawoud, M. A., D. K. Ibrahim, M. I. gilany, and A. ’F. El’Gharably, "Robust Coordination Scheme for Microgrids Protection Based on the Rate of Change of Voltage", IEEE Access, vol. 9, pp. 156283-156296, 2021. Abstract

The wide application of microgrid concept leads to challenges for the traditional protection
of distribution networks because of the changes in short circuit level and network topology during the two
modes of microgrid operation. This paper proposes a promising solution for these problems by offering
a new protection coordination scheme not affected by the variation of short circuit level or the changes
in network topology. The proposed protection scheme is based on local measurements at relay location
with low sampling frequency by computing the rate of change of fundamental voltage (ROCOV) to detect
different fault types, identify the faulty zone accurately and guarantee robust coordination between primary
and backup relays. The proposed coordination scheme can be achieved by optimizing either two settings for
relay characteristic (time dial setting and pickup value) or four settings (time dial setting, pickup and the
parameters that control the characteristic shape (A & B)). The proposed scheme is extensively tested using
MATLAB simulations on the modied IEEE 14 bus meshed network embedded with synchronous/inverter-
based distributed generation units under wide variations in operating conditions and short circuit levels
for both grid-connected and islanded modes of operation. The achieved results conrm that the proposed
coordination scheme can maintain the coordination between primary and backup relays for different fault
locations, types and different topologies. It provides selective, reliable, and secured microgrid operation
compared with conventional schemes, using fault current limiters and some other techniques discussed in
the literature.

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