Motion Performances of a 5 MW VAWT Supported by Spar Floating Foundation With Heave Plates
The VAWT (vertical axis wind turbine) has advantages in the development of large-scale offshore wind power. This paper presents a motion study of a 5 MW floating VAWT composed of the Φ type Darrieus wind turbine and a truss spar floating foundation with heave plates. The surge, heave and pitch motion equations considering the effects of retardation function of the floating VAWT were established and solved numerically. Several load cases were carried out to analyze the motion performances of the floating VAWT. The results show that the wind forces have minimal influence on the heave motions of the floating VAWT, while they obviously increase its surge and pitch mean displacements. For LC3, the surge, heave and pitch frequencies of the floating VAWT are dominated by the wave frequencies, and the 2P (twice-per-revolution) response of pitch motions is not significant. For LC4, the 2P response of pitch motions of the floating VAWT are more significant than LC4.