الفهرس 
WIND ENERGY TECNOLOGIES & CHALLENGESOnly 14 pages are availabe for public view
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Abstract
Wind power is one of the major emerging technologies in the electrical power area. In the last decades, the size of wind turbines and wind farms increased rapidly. According to the Global Wind Energy Council (GWEC)’s Annual Market update, wind power surged to a new record in 2012 with nearly 45 GW of new installations representing 10 percent increase from 2011. Global installed capacity increased roughly 19 percent to 282.6 GW.
Egypt has an excellent wind regime, particularly along the Gulf of Suez coast where the average wind speed reaches 10 m/sec. With the going rise in the electricity demand, wind energy will play a major role in the electric power system to satisfy the demand grows and overcome the expected shortage of fossil fuel and its environmental consequences. The Egyptian renewable energy (RE) strategic plan targets to contribute about 12 % of wind energy which represents about7200 MW out of the total generation mix by 2022.
The complexity of the interconnection of wind farms to the power grid stems from the fact that wind energy is rather unstable and available only during certain hours of the day. By its nature the wind power generation may DROP suddenly. A rather unique feature of wind power in Egypt is that most of the high wind resources are concentrated at Gulf of Suez and Eastern and Western banks of Nile River areas. This raises an additional operational constrain since large concentrated wind power is connected at certain points of the network and not distributed over the country.
Transmission system events (faults, equipment failures…etc) are common on utility grids. Transmission planners and system operators expect generators to tolerate and, ideally, recover from such system events. Until recently, wind turbines have been designed to trip offline in response to
instantaneous voltage drops in order to protect the wind turbine equipment until the grid recovers. In tightly interconnected grids with significant penetration of wind generation, however, this response can lead to cascading failure of the entire system.
Countries with a rather weak power system, at the point of common coupling, have to consider the impact of wind power on network stability issues, which means that they require, for example, fault ride-through (FRT) capabilities for wind turbines. Although the FRT enable the overall system to restore its stability without losing large amounts of power generations after fault clearing, these control strategies may influence the related protective elements. Relay miss-coordination or miss-operation may occur due to the resulting changes of fault current profile.
This thesis studies the impact of interconnection of large wind turbines on protection system with special care on modeling that emulate Egypt Case in some areas where wind penetration is high and at the same time no conventional generation in that area and more, the farms connected with long transmission line to the Grid. Detailed aggregated modeling for wind farms having different technologies has been done together with studying different types of faults, with different time steps. Also successful and non-successful reclosure impact has been examined. The Crowbar action and its impact on the short circuit current has been studies. Coordination between wind farms and transmission protection schemes according to grid codes has been studied in details together with the co-influence of fault ride through capability on protective relay using proper software to achieve the objective of the thesis. Recommendations on the coordination between FRT and the under voltage protection has been presented together with illustration on the impact of Crowbar setting on different Transmission Protection Systems. Then recommendations and guide for future work is presented.