A large number of offshore wind farms with fixed foundations have been installed in Europe with relatively state-of-the-art techniques. However the installation of floating wind farms in deeper water is encouraged by the stronger and steadier winds, the lower visibility, the absence of ship lanes restrictions and the economic potential. Compared to a fixed foundation, a floating offshore wind turbine (FOWT) may sustain more complicated environmental conditions including stochastic winds and waves. One of the FOWT concepts was designed and analyzed. It consists of a three bladed 5-MW up wind turbine, which is the basic model under the IEA Annex 23 Subtask 2 Offshore Code Comparison Collaboration (OC3) project, and supported by an OC3-Hywind spar buoy platform. The platform is connected by three mooring lines to the sea bed. To study motion characteristics of the OC3-Hywind platform, a model was built with a 1/128 scale ratio. The model test was carried out in various sea states, including rotating rotor effect with wind in the Ocean Engineering Wide Tank of the University Of Ulsan (UOU). The characteristic motions of the OC3- Hywind platform were captured and the RAO and significant motion were obtained.
With worldwide environmental regulations and sudden fluctuations in oil prices, the development of alternative energy to fossil fuel begins in earnest. The Korean government suggested ‘Low Carbon Green Growth’ as a new vision and the latest paradigm of national development. Korea, whose dependence on overseas energy is about 97%, chose the development of green energy as a national project. Especially because they give an impetus to floating wind power generation, we expect that our industrialization will accelerate rapidly. Normally offshore wind turbines receive better wind quality in deepwater than shallow water. Presently, most of offshore wind turbine installations are fixed support structures in shallow water.