An investigation of furl control in a direct-drive PMSG wind turbine

In order to fully study various phenomena related to small wind turbines (WTs) in wind energy conversion systems (WECSs), a comprehensive model that considers their mechanical, electrical and aerodynamic aspects is needed. One such phenomenon is furl, which is a mechanical mechanism that protects small horizontal axis wind turbines (HAWT) against excess speed and power. In this paper, a new detailed model for a small permanent magnet synchronous generator (PMSG) based WT with furling control is developed. The system under study is a variable speed WT/ PMSG configuration that uses back to back voltage source IGBT converters to connect to the grid network. For the model, software such as TurbSim and FAST was used to model a wind profile and the mechanical parts of the WT and Simulink/MATLAB was used to model the WT generator and electrical controllers; the voltage source converters (VSCs) were operated with a field oriented control (FOC) method. Simulation results that show the performance of the small WT with furling control under different environmental and network conditions are presented.