الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Railways are a safe land transport system when compared to other
forms of transport. Power is provided to locomotives which either draw
electrical power from a railway electrification system or produce their
own power, usually by diesel engines.
For electrified railways; Power is transmitted to electric railway
locomotives using DC or single phase AC networks. For AC electrified
railways it is important to ensure a reliable and secure power supply to
the traction system, therefore a suitable protection system is required. The protection system shall distinguish between the fault current and the train
load current, and isolate the fault as soon as possible.
This thesis presents the modeling and simulation of a 25 kV 50 Hz AC
traction system using Power System Block set (PSB) / SIMULINK
software package. The model has been used to study different simulation
cases considering the common types of faults.
A proposed distance relay algorithm is introduced. The performance of
the proposed distance relay is checked in case of earth faults (normal and
emergency feeding conditions), wrong phase coupling, and resistive
faults. Furthermore, the proposed relay algorithm has a fault location
function to detect the faulty subsection. The performance of fault location function is checked. Finally the proposed relay settings is selected to compromise between security requirements and sensitivity of fault
detection to meet the operational requirements The thesis consists of five chapters
Chapter (1): Gives an introduction of the railway systems and
electrification systems.
Chapter (2): Introduces a literature survey for protection systems
and material helpful for understanding the problem AC feeding system
protection for electrified railways.
Chapter (3): Introduces the modeling methodology of the proposed
distance relay algorithm.
Chapter (4): Introduces simulation and results for the proposed
distance relay algorithm.
Chapter (5): Presents the extracted conclusions and future work
suggestions.