Impact estimation of electrical disturbance onto turbine structural behavior of wind power system

A wind power generation system consists electrical, mechanical, aerodynamics and structural dynamics in its model. However, the most of the reported system dynamic models include either electrical and mechanical dynamics or structural and aerodynamics. This may sometimes lead to imperfect analysis when someone is observing impact of the electrical disturbance onto the structural dynamics. Therefore, this paper presents the complete model of the wind power system considering aerodynamics and structural dynamics of the blade along with the electrical and mechanical power balance. Also, the detection of the blade vibration using electrical measurements have been performed through a nonlinear estimator, named Unscented Kalman Filter (UKF) which may further helps to design a controller without additional sensors. The estimation of the impact of the electrical disturbance onto the blade vibrations provide insights into the early detection and observation of the blade vibrations. It was observed that a frequency of edgewise vibrations of the blades of 1.159 Hz other than the fundamental frequency corresponding to the speed of the rotation of the wind turbine, is introduced when the system subjected to an electrical disturbance and it should be taken care of during the control design. Further, the UKF estimates these vibrations perfectly, closely matching with the actual frequency with an estimation error of only 0.35%. The structural model is prepared using Euler–Lagrangian method (ELM) while Blade Element Momentum method (BEMM) is used for aerodynamic power and forces. The structural and blade geometry data of NREL’s 5-MW wind turbine have been used for the simulation while the structural model of the wind turbine have been validated using NREL’s tool FAST.