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Tahir Khurshaid,Abdul Wadood,Saeid Gholami Farkoush,김창환,조남훈,이상봉 대한전기학회 2019 Journal of Electrical Engineering & Technology Vol.14 No.1
The coordination of directional overcurrent relays (DOCR) plays a very important role for maintaining security and enhancing reliability in the electrical power system. This paper presents the coordination of directional overcurrent relay using the modified particle swarm optimization (MPSO) technique. In order to improve the quality of a solution a local search algorithm is embedded to the original particle swarm optimization (PSO). Time dial settings had been optimized for directional overcurrent relays. In PSO technique on implementing the DOCR, being a highly constrained optimization problem that takes into consideration the linear programming. To handle such constraints a modification to PSO algorithm has been introduced. MPSO has achieved a lot of relaxation to its easy implementation, modesty and robustness. The proposed algorithm had been tested on IEEE 6-bus, IEEE 15-bus system and IEEE 30-bus system using MATLAB computer programming.
Gray Wolf Optimizer for the Optimal Coordination of Directional Overcurrent Relay
Kim, Chang-Hwan,Khurshaid, Tahir,Wadood, Abdul,Farkoush, Saeid Gholami,Rhee, Sang-Bong The Korean Institute of Electrical Engineers 2018 Journal of Electrical Engineering & Technology Vol.13 No.3
The coordination of directional overcurrent relay (DOCR) is employed in this work, considering gray wolf optimizer (GWO), a recently designed optimizer that employs the hunting and leadership attitude of gray wolves for searching a global optimum. In power system protection coordination problem, the objective function to be optimized is the sum of operating time of all the main relays. The coordination of directional overcurrent relays is formulated as a linear programming problem. The proposed optimization technique aims to minimize the time dial settings (TDS) of the relays. The calculation of the Time Dial Setting (TDS) setting of the relays is the core of the coordination study. In this article two case studies of IEEE 6-bus system and IEEE 30-bus system are utilized to see the efficiency of this algorithm and the results had been compared with the other algorithms available in the reference and it was observed that the proposed scheme is quite competent for dealing with such problems. From analyzing the obtained results, it has been found that the GWO approach provides the most globally optimum solution at a faster convergence speed. GWO has achieved a lot of relaxation due to its easy implementation, modesty and robustness. MATLAB computer programming has been applied to see the effectiveness of this algorithm.
Gholami Farkoush, Saeid,Khurshaid, Tahir,Wadood, Abdul,Kim, Chang-Hwan,Kharal, Kumail Hassan,Kim, Kyu-Ho,Cho, Namhun,Rhee, Sang-Bong Hindawi Limited 2018 Complexity Vol.2018 No.-
<P>A large number of electromagnetic transient studies have been analyzed for finding the overvoltage behavior of power system. A grounding grid of power system is so important for reducing the effect of overvoltage phenomena during a short-circuit event. Two sections are important in grounding system behavior: soil ionization and inductive behavior; this paper focuses on the inductive manner of grounding grid. The grounding grid is considered as a conductor segment; each conductor segment acts as a grounding unit. In this paper, the transient methodology is introduced to investigate the lightning effect on grounding body at each point of grounding grid in normal and optimized conditions. Genetic algorithm is applied for regular and irregular grounding grid to obtain best values of mesh size with the lower ground potential rise (GPR) as compared with the normal condition for more safety. The grounding grid is a combination of inductance, resistance, and capacitance. This model is suitable for practical applications related to fault diagnosis. Several voltages on different positions of grounding grid are described in this paper using ATP-EMTP and genetic algorithm. The computer simulation shows that the proposed scheme is highly feasible and technically attractive.</P>
Gray Wolf Optimizer for the Optimal Coordination of Directional Overcurrent Relay
Chang-Hwan Kim,Tahir Khurshaid,Abdul Wadood,Saeid Gholami Farkoush,Sang-Bong Rhee 대한전기학회 2018 Journal of Electrical Engineering & Technology Vol.13 No.3
The coordination of directional overcurrent relay (DOCR) is employed in this work, considering gray wolf optimizer (GWO), a recently designed optimizer that employs the hunting and leadership attitude of gray wolves for searching a global optimum. In power system protection coordination problem, the objective function to be optimized is the sum of operating time of all the main relays. The coordination of directional overcurrent relays is formulated as a linear programming problem. The proposed optimization technique aims to minimize the time dial settings (TDS) of the relays. The calculation of the Time Dial Setting (TDS) setting of the relays is the core of the coordination study. In this article two case studies of IEEE 6-bus system and IEEE 30-bus system are utilized to see the efficiency of this algorithm and the results had been compared with the other algorithms available in the reference and it was observed that the proposed scheme is quite competent for dealing with such problems. From analyzing the obtained results, it has been found that the GWO approach provides the most globally optimum solution at a faster convergence speed. GWO has achieved a lot of relaxation due to its easy implementation, modesty and robustness. MATLAB computer programming has been applied to see the effectiveness of this algorithm.
Tahir Khurshaid,Chang-Hwan Kim,Abdul Wadood,Sang-Bong Rhee 한국조명·전기설비학회 2017 조명·전기설비학회논문지 Vol.31 No.10
With the expanding size of the power system, there is a certain way of finding solutions to maximize the utilization of existing systems and to provide adequate voltage support. For this, power flexibility is needed. A flexible AC transmission system (FACTS), if located optimally, can be useful in providing voltage support and controlling power flow, which in turn results in lower losses in deregulated power system. This paper proposes a method of finding the optimal location of unified power flow controller (UPFC) to relieve congestion using a sensitivity analysis approach by the Fast de-coupled methodology. The impact of these gadgets on line flows and bus voltage profiles has been studied by placement at the line which is the most positive sensitive or more negative sensitive location and placing them optimally with optimal ratings dictated by sensitivity analysis, in order to reduce losses and improve the voltage profile. The effectiveness of the developed algorithm has been tested on an IEEE 14-bus system.
Mobile geolocation techniques for indoor environment monitoring
( Ridha Ouni ),( Monji Zaidi ),( Maazen Alsabaan ),( Wadood Abdul ),( Amr Alasaad ) 한국인터넷정보학회 2020 KSII Transactions on Internet and Information Syst Vol.14 No.3
Advances in localization-based technologies and the increase in ubiquitous computing have led to a growing interest in location-based applications and services. High accuracy of the position of a wireless device is still a crucial requirement to be satisfied. Firstly, the rapid development of wireless communication technologies has affected the location accuracy of radio monitoring systems employed locally and globally. Secondly, the location is determined using standard complex computing methods and needs a relatively long execution time. In this paper, two geolocalization techniques, based on trigonometric and CORDIC computing processes, are proposed and implemented for Bluetooth-based indoor monitoring applications. Theoretical analysis and simulation results are investigated in terms of accuracy, scalability, and responsiveness. They show that the proposed techniques can locate a target wireless device accurately and are well suited for timing estimation.
Wali Muhammad,Wilayat Husain,Anjum Tauqir,Abdul Wadood 대한용접·접합학회 2020 대한용접·접합학회지 Vol.38 No.5
In this study, the Taguchi Design of Experiment method was used to determine the optimal Friction Stir Welding (FSW) parameters for improving the mechanical properties of AA 2014-T6 alloy butt joints. The three most significant parameters - tool rotational speed, tool linear travel speed and tool tilt angle - were optimized using the L9 orthogonal array design. The optimal welding parameters for the maximum tensile strength were determined by analyzing the signal-to-noise (S/N) ratio. A regression model was developed for the desired responses. The optimal tensile strength was achieved at the 1000 rpm, rotational speed, 600 mm/rev welding speed, and 2° tool title angle. The results were confirmed using a steady-state heat transfer model generated from the COMSOL Multiphysics Finite Element software. The identified optimal conditions were verified by experimental validation tests. The experimental results were consistent with the predicted values. Analysis of variance (ANOVA) was conducted to determine the effects of individual parameters and to identify the most significant process parameter. ANOVA indicated that the most significant factor affecting the mechanical behavior of the joint was the tool rotation speed followed by the linear travel speed.