Dynamic response analysis of alternative mooring system designs for a 15 MW floating wind turbine with an emphasize on different limit states

Abstract

With the advancement of wind turbines into deeper and more distant waters, and the increase in turbine power, the design of mooring systems for large floating wind turbines presents significant challenges. This paper, based on a water depth of 100 meters, focuses on a 15 MW eccentric semi-submersible wind turbine platform. A time-domain fully coupled numerical model is established, and the mooring system design is carried out. A parametric investigation is conducted on the influence of different mooring parameters on the floater's motion, line configuration, mooring tension, and pretension. The study considers operational conditions, extreme conditions, and accidental conditions such as mooring line failure. It emphasizes the effects of factors such as mooring line length, horizontal mooring angle, fairlead height, and components in hybrid mooring systems, including concentrated mass, buoy volume, and the configuration scheme of weight and buoy blocks. Among various mooring schemes, an optimized design is selected for further dynamic response analysis to verify the feasibility of the scheme. Through comprehensive analysis of various mooring parameters, this paper summarizes the influence patterns of different mooring system design parameters on the dynamic response of floating wind turbines, providing a theoretical foundation and design guidance for subsequent engineering applications.