Research Projects

Wind energy is a sustainable, renewable, and cost-effective source of electricity. However, increasing demand for harvested energy leads to slender and flexible turbine blades, resulting in excessive wind-induced vibrations that affect turbine efficiency and component lifetime. Flutter instability can be catastrophic, causing system collapse and impacting post-disaster rehabilitation. To address this issue, research on efficient vibration control strategies for wind turbines is necessary. Currently, commercial wind turbine models are based on linear theory, which is inadequate for modern turbines with long, flexible blades and high rotor speed. Studies on aeroelastic instability (flutter) and its control for wind turbine blades are scarce. Passive control systems require large masses and performance degrades due to mistuning. Active control systems are less reliable and require external power supply, which may not be available during extreme events. To address these issues, a nonlinear aeroelastic model of wind turbines will be developed by combining the structural model using a geometrically exact beam theory and the aeroelastic model using modified Blade Element Momentum theory with Theodorsen's approach to include self-excitation. This model will incorporate all significant dynamic characteristics of wind turbines, ensure reliable aerodynamic responses and flutter speed. Vibration control systems like MR dampers with output feedback control or piezoelectric bimorph can be considered for vibration control. These systems are reliable, require less power, and use only few measured outputs for feedback. Efficient and reliable vibration control will enhance blade lifetime and power output, boosting the economic viability of wind turbines.