Performance Optimization of Floating Offshore Wind Turbines with Wave Oscillation

Carlos Armenta-Deu; Daniel Martínez

Abstract

In this paper, the influence of wind turbine tilt due to wave effects on the power generation has been studied and analyzed to optimize the performance of floating offshore wind turbines (FOWT). A simulation process has been developed to determine the optimum tilt angle at which the wind turbine delivers the maximum power. The simulation has been applied to a marine wind turbine with articulated hinge, which allows to correct small inclination angles caused by wave oscillation, leading to a power gain, and to a pitch motion non-hinged hub wind turbine with optimum pitch angle. The simulation has shown that the output power of the wind turbine is not symmetric related to a null tilt angle, with maximum power for a tilt angle of 2º to the windward direction. Power generation gain corresponds to a windward direction angle in the range 0º to 4º. The reduction in power generation for the non-hinged hub wind turbine with pitch motion is of 5.4% for the tilt angle range used nwadays in real conditions; this reduction, however, is limited to 0.8% if dealing with an articulated hub wind turbine. A non-symmetric tilt angle range is shown as the most adequate to optimize the wind turbine performance for the non-hinged hub wind turbine. Nevertheless, for the articulate hinged hub configuration the performance reveals a more homogeneous performance with symmetric range of the tilt angle related to the null tilt value. Power loss reduction can be obtained through a polynomial correlation for both, articulated and non-hinged hub, configurations. This correlation shows a very high accuracy, better than 99.7, allowing to set up the optimum tilt angle range for a specific setup value of power loss factor.

Abstract

Keywords