Parametric Study of a Minimal Model of Wind Turbine Drivetrain System

Abstract

There are several types of renewable energy, produced from different sources. One of the most efficient renewable today is the wind energy. In the case of wind power, the kinetic energy of the wind drives a generator which produces electricity. The drive train is an important component in realizing reliable and robust wind turbines. This research work investigates the dynamic behavior of a horizontal axis wind turbine drivetrain under different excitation sources. The present paper developed an 11° of freedom (DOF) dynamic model of wind turbine geared transmission system. This model includes the main factors such as the time-varying mesh stiffness, bearing stiffness and damping. The aerodynamic driving is also defined taking into account the size of the blades and the average wind speed. Using the implicit Newmark’s method, the dynamic response of the bearing and the transmission error of the wind turbine gearbox is presented with the time signal and Fast Fourier Transform (FFT) spectrum. The results show the different vibration levels of the bearings and the effect of the wind speed and the gear ratio on the dynamic behavior of the system. Finally, a time-frequency representation is used to have more information about our system dynamic behavior.