In the present days the growing of the rail freight transport and the worldwide excessive spreading of the high-speed tractions are permanently claims new needs regarding the railway electrification methods. The most important and essential requirements of the modern railway feeding systems are the higher transmission capability and as less inducing effects on the other installations (telecommunication and low voltage networks pipelines etc.) as possible. In this thesis work, the a.c. special feeding systems are principally discussed.
The first chapter gives a brief overview of the history of railway electrifications including their roles in present-days and their most important features.
The second chapter of the thesis describes the different railway feeding systems, with particular regard to the a.c. fed systems.
In the third chapter the followings are introduced: the construction, the function and the benefits of the booster transformer (BT) feeding systems with rail return (BTRR), or with return conductor (BTRC) and finally the auto transformer (AT) system.
In the fourth chapter of the thesis I analyze the feeding systems using the simulation test results of . The aim of this part is the comparison of these systems from the equivalent line impedance, voltage drop, rail potential and inducing earth current points of view.
The last section provides the summary of the main features of the feeding systems. Finally some application examples are presented for the studied feeding systems.