With the rapid development of wind energy technology, offshore wind turbine attracts more and more attention. Foundation of offshore turbine plays an important role in the stability of the whole structures. So far the most of the existing offshore turbines have been installed with monopile or gravity base substructures. Although the monopile is still an option for the larger wind turbine, development of more cost effective solution for large scale wind turbine is under investigation. In this study, tripod and jacket foundations are compared with the monopile structure. Generic 5-MW NREL model was used as the baseline model in this work. It was aimed to investigate the basic properties and load response of wind turbine with different support structures under several primary design load cases with Korean local environmental conditions. Coupled aero-hydro-servo-elastic model with full flexible components including the blades, tower, drivetrain and foundation was used in the simulation. Modal analysis is carried out to determine the vibration characteristics (natural frequencies and mode shapes). A typical load comparison regarding to different support structures was performed also.
At the present time, renewable energy has grown significantly with the development of industry. Especially offshore wind energy is attracting more attention in recent years because offshore wind could provide better wind condition with less turbulence. Since the first OWT was constructed in Denmark, the offshore wind industry has developed gradually. South Korea is going for an ambitious offshore wind farm amounting to $8.3 billion. This project will be executed at the western coast of the Korean peninsula taking a time period of nine years. But so far more work and research based on local design conditions are required in South Korea. The cost effectiveness of electrical power generation from wind energy increases with the implementation of larger turbines.
