الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Transformers substations play a vital role in electrical power system. They step up or step down voltages to be ready to transfer power to far places. Any power system consists of three stages: generation, transmission and distribution. Transmission system is essential to connect generation grid system to distribution system. Transmission system has transformers substations to control the rating of voltage. Transformers substations deal with high voltage and all components in the substation that need to carefully be handled. In the substation, workers should work in a safe place and this will not happen until putting a good grounding grid system beneath the land of substation. Grounding grid system is essential for not only for workers but also for all components of the substation. Grounding grid system can grantee that persons in the area of substation are not exposed to danger of an electrical shock. Moreover, it can carry currents and absorb them into earth under normal or fault operation, which helps sustain the continuous operation of the system and equipment. In this thesis, the design of grounding grid system for transformers substation will be introduced according to international standard IEEE 80-2000. ETAP12.6 will be the simulation program to design a grounding grid. The thesis will study the effect of increasing loads and power sources of substation on the performance of grounding grid system and provide solutions should any problem arises. The research sets forth new methods to design grounding grid system and discusses their advantages and disadvantages of each proposed solution. Solutions can be divided into four methods; consolidation of old conventional grid, division of the grid into multi small grids, vertical design for the grid and making the design around the borders. Comparison between new proposed methods explains the difference between each method and other. Among the proposed new methods, the best one is shown to be the vertical design of the grid. Vertical design is considered to be the best solution to overcome the problems of grounding grid system. It can help anyone to reach the grounding system at any time during energizing substation easily and workers will be far from civil works of the substation in all circumstances. Ultimately, the grid can increase gradually to withstand any increase in earth fault current, with increased numbers of conductors and earthing rods.