Block Diagram Simulation of a Large Horizontal Axis Wind Turbine

In the present study, block-diagram simulation of a reference horizontal axis wind turbine with pitch-regulated mechanism is presented. The aim of this simulation is modeling of wind turbine subsystems to investigate the transient behavior of the turbine under unsteady incoming wind. Analytical approximation model is used to estimate the output power coefficient. In addition, PID controller is imposed to regulate the output power via changing the blade pitch angle. Governing equations of the mechanical part (i.e. gearbox), electrical part (i.e. three-phase doubly fed induction generator), aerodynamic and controller models are implemented in LMS AMESim software package. The model uses a purely torsional multi-body simulation to show the dynamic behavior of gearbox. The proposed model is used to investigate the rotor transient behavior as well as the controller performance under the conditions that the wind speed changes linearly from 21 to 8 m/s during 130 seconds. The results show acceptable accuracy in comparison with the reference data.