Braceless semi-submersible floating offshore wind turbine (FOWT) is subjected to environmental loads during its service, and the different combinations of wind, wave, and current environmental loads have different contributions to the motion responses of the offshore wind turbine platform. Under the different water depth of 100m, 150m, 200m, the time domain motion response calculation model of floating wind turbine platform was established, and the corresponding time-domain motion of wind turbine platform with six degrees of freedom and the mooring line tension were analyzed. The results show that the maximum motion response and mooring line tension are all in line with the engineering requirements. The results of this study provide reference for further research on the design of mooring system.
In recent years, social and economic development has been excessively dependent on the use of traditional fossil energy, resulting in serious environmental pollution and climate change. Therefore, governments around the world have introduced targeted policies to address the corresponding environmental pollution and climate change issues and reduce dependence on traditional energy, while promoting the development of new renewable energy. Wind energy has become the mainstay of renewable energy in the sustainable development of human society due to its advantages of small pollution, large reserves, wide distribution and mature research technology. China is one of the countries with the largest wind resources in the world (Zhao, 2019). More than 18,000 km of coastline on land and 3 million km2 of sea area are available. The reserves of wind energy resources at 10 m height are 3.226 billion KW. The total reserves of land wind energy that can be utilized are 253 million KW. Furthermore, the total reserves of offshore wind energy are more than three times the total reserves of land wind energy, which are nearly 1 billion KW. According to the statistics of the Global Wind Energy Council (GWEC) (Sun, 2019), the total installed capacity of the wind turbine reached 591 GW. The new installations of China reached to 21.14GW, bringing the total installed capacity to 210GW, which make China the first country in the world to install more than 200GW.
