الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The ac generation stations are one of the most important parts of the electrical power system, therefore studying how to protect it against fault currents by making a reliable design of a grounding system is very important. The aims of a grounding system are to provide safety of the personnel during normal and fault conditions, to assure correct operation of electrical devices and to prevent damage of electrical apparatus. While grounding grid performance can be evaluated in terms of grounding resistance, it is also important to include touch and step voltages as significant indictors for the grounding quality.The main objective of this research is to present the concept of designing a grounding system for the Cairo North Power Station 1500 MW using different approaches. The thesis also reviews the parameters that affect the design of a grounding system of ac generation stations, such as soil type,depth, conductor, material and spacing, human body current, etc...Currently the IEEE 80-2000 standard for substations grounding limits the determination of the grounding parameters (namely step, touch and ground potential rise) to that of a uniform soil model unless the master curve method is used. With the master curve method, it becomes possible to interpret the measurements to obtain a more accurate two layer soil model which has been carried out in the present work.An alternate method has been applied according to which, using a set of soil’s resistivity measurements, one can compute the parameters of the multilayer earth structure using a genetic algorithm (GA). The results provided by the GA constitute the data that can be used in field simulations of grounding systems.The computer program ETAP is a well known comprehensive analysis platform for the design and simulation of industrial power systems,and is applied, here, for the design of the grounding grid of the Cairo North Power Station using both the IEEE method and the Finite Element Method.III The results of the different methods are analyzed and evaluated for a proper design of the Cairo North Power Station. Comparative analysis of the results is carried out based on the values of the computed step, touch and mesh voltages and their standard tolerable values.Finally, conclusions and recommendations for future work are reported.