Analysis of a Two-Bladed Flexible Rotor System: Model Development Progress

Designing wind turbines to be fatigue resistant and to have long lifetimes at minimal cost is a major goal of the U.S. Wind Energy Program and the wind industry. To achieve this goal, we must be able to design wind turbines that exhibit reduced loads compared to current machines. One possible method for reducing structural loads in wind turbines is to design machines with very flexible components. At the National Renewable Energy Laboratory (NREL), we are beginning to model a very flexible wind turbine with some of our simulation codes. We first describe briefly the simulation codes used in this study. We then describe the wind turbine we analyze. We then describe analytical model development progress for this flexible rotor and show a preliminary side-by-side comparison of predictionsfrom two different wind turbine simulators for this machine for some different operating cases. We then make conclusions and state our plans for future studies.