From the center of wind pressure to loads on the wind turbine: A stochastic approach for the reconstruction of load signals

Abstract. In the context of the wind industry, there is an increasing need for a more comprehensive understanding of the atmospheric wind, particularly with respect to wind structures, which have not been thoroughly investigated in the current standard guidelines. This necessity arises in light of the current trends toward larger, higher, and more flexible wind turbine designs. Of particular importance are the correlations between the yet-to-be-characterized atmospheric turbulent structures and the specific responses of the turbines. These correlations may be crucial in assessing load events relevant to new designs that were negligible for the earlier, smaller, and stiffer turbines. The Center of Wind Pressure (CoWP) (Schubert et al., 2025) was recently introduced as a feature of a wind field that characterizes large-scale wind structures and, at the same time, correlates with the large-scale or low-frequency content of the bending moments at the main shaft of the wind turbines. In this paper, we comprehensively compare the CoWP and the bending moments in terms of their statistical properties and fatigue estimates, quantified by Damage Equivalent Loads (DEL). Furthermore, a stochastic method for the reconstruction of synthetic CoWP signals is proposed. The strong correlation with the bending moments allows the proposed stochastic CoWP model to be used as a surrogate and relatively simple estimator of the large-scale dynamics of these loads, which is based solely on the properties of the inflow wind field. A notable advantage of the approach is the capability to reconstruct very long time series, which are critical for assessing loads over the operational lifetime of the turbine. As an alternative, the proposed stochastic model of the CoWP from atmospheric data can be integrated as an extension of existing wind turbulence models, thereby accurately reproducing the dynamics of large-scale wind structures inherent to the CoWP.