Study On Load Characteristic Of Large Wind Turbine Blades

Wind turbine is the most important wind energy device, converting wind energy intomechanical energy through rotor, and into electricity through a generator finally. It works incomplex environment, undertaking random and alterating load, and is especially affected bythe wind shear, tower shadow and other factors, making the load characteristics of windturbines more complicated. The blades are main load bearing parts. As a result, the research ofblades load characteristics can provide important conference for tructural design and fatigueanalysis of large-scale wind turbines.The wind characteristics in external operation environment of wind turbines was studied,considering wind shear, tower shadow and upwind turbine wake. The theoretical basis of threeturbulence models was discussed and Von karman model in accordance with real wind featurewas adopted as simulation model.Based on aerodynamics theory, the calculation method of blades load, i.e., blade elementand momentum theory, was introduced. Through the analysis of blades load type, the formulawas deduced. The model of2MW wind turbine was established, and the steady charateristicsand steady operation load were calculated. The factors that affect design performance of windtuebine was analysised with the help of GH Bladed software, from the result of which it can beconcluded that the blade can be destroyed more easily at root. According to the design loadcases of GL2010, many kinds of wind turbine operation state were simulated. The dynamicload on blade root was calculated by loading on the three dimensional turbulence model. Thesimulation results were obtained, and for which the post processing work such as periodiccomponent analysis, spectral anslysis, ultimate load calculation under various condition, werecomplished. The related load changing curves at blade root were obtained, which can be takenas reference for intensity verification and frequency domain analysis.