Structure Dynamic Analysis of a Horizontal Axis Wind Turbine System Using a Modal Analysis Method

Abstract

This paper considers the structural dynamic analysis of horizontal axis wind turbine (HAWT) rotor blades. Initially a blade from a 300 W machine was used, using both experimental and theoretical modal analyses. In the experiments, a DAS (Dynamic Signal Analysis and Fault Diagnosis System) was used to extract modal parameters by measuring vibrations at various locations along the blade surface. A finite element analysis (FEA) method was used for the theoretical modal analysis. Comparison of experiment and theory explains the low order vibration conditions. The effects of different constraint conditions of the FE model are discussed. Finally, theoretical modal analysis is used to analyze a 600 kW rotor blade. The results are compared with those calculated using ‘Bladed for Windows’ of Garrad Hassan and Partners Ltd (UK), and satisfactory agreement between them is obtained.