الفهرس 
Ageneral overview for transmission line.Only 14 pages are availabe for public view
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Abstract
Composite transmission systems of both overhead line and cable segments are subjected usually to some certain conditions different from those ones with their counterpart of overhead lines. Different factors participated into these problems including the lower reactance values of cable segment(s) as compared with those segment(s) for overhead line parts, the lower x/r ratio for cable segments and the relatively larger capacitive currents. In this thesis, an investigation of the associated problems of distance relaying with composite lines is presented. The core of these problems is firstly emphasized. Then, their causes, effects and their proposed solutions are outlined. Both simulation and recorded fault cases from the field are employed. A multi-section intertie transmission system is considered connecting both Egyptian and Jordanian networks. It comprises double circuit overhead line, submarine single core cable, and single circuit overhead line in addition to the termination substation and sub-transmission. The line is accurately modeled in order to carry out different power system studies emphasizing the protection perspectives. The simulation phase includes the Electromagnetic Transient Program (EMTP) and Matlab files linked in one arrangement, in which they are the most common packages for developing simulation studies. Different solution strategies are proposed aiming to present practical solutions for these problems. First the communication strategy is modified. Another solution is proposed with employing the ANNs as an AI tool for providing an intelligent solution for these problems.