Postal address:

Wybrzeze Wyspia6skiego 2750-370 WroclawPOLAND

Building: D-20

Tel: 0-77 3202655Tel/fax: O-71 3202656

Email: Inst.Energ@pwr.wroc.plHttp://www.ie.pwr.wroc. pl

Wroclaw University of Technologylnstitute of Electrical Power Engineering

Wroclaw, November sth, 2013

Dr Yesri ZakiMahammad

I appreciate very much receiving from you the drafts of the books:

1. An Introduction to the Digital Protection of Power Systems, 162 pages

2. An Advance Course in Power System Protection, 5 lectures.

After careful studying of them I would like to say that those are very good

materials which are suitable for use by our students studying at the M.Sc.specialisations: Control in Electrical Power Engineering and Renewable Energy

Systems. The teachers in our Institute including myself will recommend this two drafts

as the literature for the courses: Power System Protection, Digital Signal Processing

for Power System Protection, Power System Faults and M.Sc. theses related to those

subjects. Therefore those two drafts will be sent to our Faculty Library to be availablefor all interested students. Also I will appreciate receiving from you the pdf files of thebooks to include them on the web sites with materials for students.

Thank you very much for nice and fruitful cooperation.

Yours sincerely

UTU

Prof. dr. Jan IzykowskiDirector of Institute of Electrical Power Engineering

Wroclaw University of TechnologyWroclaw, Poland

e-mail : j an.izykowski@pwr.wroc.pl

DYREK

,r.f.O1

PREFACE

The applications of digital techniques in power system protection have been established in 1969, and since then, those applications have been received accelerating interest. The growing abilities of the digital computers and hence the digital relays, make them to be more powerful and cheaper than the analog relays. The advance development in hardware engineering has been followed by a rapid protection engineering studies to create new digital protection algorithms. The main goal of these studies is to reduce the operation time, and to increase both security and selectivity of the proposed algorithms.

Digital protection developments have been published in scientific and technical literatures, such as the proceedings of transactions, the proceedings of conferences, the publications of the various manufacturers, and in a limited number of books in this field. Any researcher or professional engineer, who is interesting in studying a special problem in the digital protection field, finds himself surrounded by many references that he has to dive in.

Therefore, books which can be regarded as an adequate introduction to the digital power system protection, become more than necessary. I was thinking in this book to include most of what a student, a researcher, or an engineer needs to go deeper in this field. It was difficult task but I found it important. Thank God, this book comes true, and it can be developed in the future. In a world becomes day by day more digitally, I have the wish that through this book, I have been giving a hand to those who start the first step.

Dr. Yesri Zaki Mohammad

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