Analytical Formulae for Wind Turbine Tower Loading in the Parked Condition by Using Quasi-Steady Analysis

Abstract

The analytical formulae are proposed to estimate the maximum value for along-wind load and across-wind load on the wind turbine towers by using the quasi-steady analysis. The critical parameters in the standard deviation such as the mode correction factors, aerodynamic damping ratios, size reduction factors and wind load ratios are investigated to identify their directional characteristics. A non-Gaussian peak factor is necessary for the along-wind load, while a Gaussian peak factor is acceptable for the across-wind load. A loads combination formula is proposed in order to consider the correlation of along-wind load and across-wind load. The proposed formulae show the favorable agreements with the full dynamic simulation.