Study of control strategies for variable speed wind turbine under limited power conditions

The paper investigates the performance of variable speed wind turbine (VSWT) configuration with DC-DC converter under restricted output power conditions. The considered regimes of turbine operation are: at maximum available aerodynamic power and at limited output electric power. The wind turbine system consist of synchronous generator (SG) connected to diode rectifier, DC chopper and load. Two different control methods are used: with predefined turbine characteristics and with fuzzy logic controller. The turbine controllers combine the maximum power point tracking (MPPT) and limited power point tracking (LPPT) algorithms. The performance of the dynamic models and the control loops are tested under various wind conditions. The simulation results are shown. The results prove the strategy and models reliability.