• Weijtjens, Wout
• Sadeghi, Negin
• Noppe, Nymfa
• Robbelein, Robbelein
• Devriendt, Christof

Abstract

With several offshore wind farms (OWF) in Europe entering the second half of their design<br/>lifetime, the offshore wind industry is increasing its focus on the period beyond the intended<br/>design life. This study focusses on an alternative to decommissioning beyond the certified<br/>operational period: extension the lifetime of the assets. In this context, the domains of lifecycle engineering and structural health monitoring (SHM) are increasingly gaining attention.<br/>However, to date, there is no consensus in the offshore wind industry on the methodology to<br/>perform such assessments. [1]<br/>The fatigue limit state (FLS) is often the main driver for designing wind turbine generator<br/>(WTG) support structures. Earlier work with real-world SHM data indicated that the<br/>consumed fatigue life is less than expected during design phase. [2]<br/>This poster presents a case study of a data-driven FLS assessment of a specific primary steel<br/>weld based on more than 5 years of real-world SHM and SCADA (Supervisory Control And<br/>Data Acquisition) data. The data-driven methodology is such that there is no need to perform<br/>aero-elastic load simulations. The potential for lifetime extension is identified by assessing<br/>the accumulated fatigue damage for theoretical and modified modelling scenarios.<br/>The study included validation of the some key principles in the data-driven assessment and<br/>the general industry consensus that the as-is environmental and operational conditions (EOC)<br/>are favourable compared to the earlier, theoretical, considerations.

Topics

• impedance spectroscopy
• phase
• simulation
• laser emission spectroscopy
• steel
• fatigue