PhD Project: Nonlinear Multibody Dynamics of Wind Turbines

In recent years wind turbines have been growing in size without corresponding increase in stiffness of tower and especially wings due to a wish for largely optimized structures. This makes wind turbines more flexible and vibration sensitive. Sea turbines with a nominal effect of up to 10 MW and a rotor diameter of 175 meters, placed on water depths as deep as 20 meters are under serious consideration. Structures of that magnitude and under those conditions are severely dynamically sensitive. To control the dynamic response of structures of that size and under those conditions, more sophisticated numerical schemes are required than the ones used today. One of the purposes of the Ph.D. project is to construct a nonlinear multibody program for simulating the dynamics of a wind turbine. Due to the complexity of such a program and the theories behind the models, collaboration between AAU and DTU is ongoing. For active control of the dynamic response it is necessary with a reduced numerical model which can be processed in real time. Therefore, system reduction algorithms for the substructures in the multibody formulation become necessary. Projektet er støttet af Det Strategiske Forskningsråd under VE-puljen.