Size optimization of a tripod-shaped support structure for weight-efficient offshore wind turbines

Paper in proceeding, 2025

Upscaling is a global trend in the offshore wind industry. Following this trend, it is inevitable that the traditional support structure - a single tower-based structure - has to withstand a bigger bending moment at the tower base. Multiple leg-based support structures have been suggested as solutions to circumvent this problem. This paper explores structural (size) optimization of multi-legs based support structures in the early design phase. Multi-objective particle swarm optimization is used to determine the tubular cross-section properties of tripod legs: outer diameters and thicknesses for weight-efficient offshore wind turbines. Inspired by X1 Wind’s concept design for the floating offshore wind turbine, a bottom-fixed tripod with NREL 5 MW reference turbine is designed and simulated using Ashes software. The optimization primarily considers the tripod weight of the support structures, and the strength of tripod legs under uniform wind loads based on a guideline, API-RP-2A