Employing of shunt damping method to reduce edgewise vibration of small size wind turbine blade with considering the effect of vibration coupling

In this paper, the vibration reduction of a small-scale horizontal axis wind turbine blade is investigated using the shunt damping method by considering the coupling between edgewise and flapwise vibrations. First, the nonlinear differential equations governing the blade dynamics with shunt damper are derived using the Lagrange method. Then, by performing the sensitivity analysis and selecting the appropriate cost function and constraints, the shunt damper parameters are optimized using the genetic algorithm method for a real blade. It should be noted that in this study, the wind force applied to the blade is considered sinusoidal with variable frequency at four different speeds. After solving the governing dynamic equations, to evaluate the effectiveness of the mentioned method in reducing vibrations, the obtained results in this study are compared with the corresponding results of employing the optimized tuned mass damper for suppression of edgewise vibrations of the blade. Results show that the tuned mass damper and shunt damping method have good effects on reducing vibrations. Despite that, the tuned mass damper effect on vibration reduction at high wind speeds is greater than the shunt damping method, at low wind speeds, the shunt damping has a greater effect on reducing vibrations.