Mohamed Hassan Hashem Ibrahim <br/><br/>
Attenuation of transformer inrush current using controlled switching system on Delta-Star transformer /  
 تقليل تيار الاندفاع للمحول بإستخدام نظم التحكم بالتشغيل على محول دلتا-ستار 
Mohamed Hassan Hashem Ibrahim ; Supervised Ahdab Mohamed Kamel Elmorshedy , Ahmed Mohamed  Emam  
 - Cairo :   Mohamed Hassan Hashem Ibrahim ,   2019 
 - 98 P. :   charts ;   30cm 
<br/><br/>Thesis (M.Sc.) - Cairo University - Faculty of Engineering - Department of Electrical Power and Machines  
<br/><br/> Reduction and methods of control of switching transients have become important concerns to the power industry. Power transformers are vital components in electric power system. This thesis presents a technique for attenuation of transformer inrush current. The proposed technique is applied to 66/11.5 kV, 25 MVA power transformer with delta connected winding using ATP-EMTP software. The main idea of the proposed technique is using controlled transformer energization preceded by controlled de-energization to achieve a defined and repeatable residual flux with its lowest possible level for individual phases, and then determine the optimal instant of energization considering the core residual flux 
<br/><br/>
<br/><br/><label>Subjects--Index Terms: </label>Controlled switching system  Inrush current mitigation  Residual flux