Advanced Pitch Angle Control Based on Fuzzy Logic for Variable-Speed Wind Turbine Systems

In this paper, an advanced pitch angle control strategy based on the fuzzy logic is proposed for the variable-speed wind turbine systems, in which the generator output power and speed are used as control input variables for the fuzzy logic controller (FLC). The pitch angle reference is produced by the FLC, which can compensate for the nonlinear characteristic of the pitch angle to the wind speed. With the control variables of the generator output power and speed, the wind turbine is smoothly controlled to maintain the aerodynamic power and its speed at the rated values without any fluctuation in the output power and speed in the high-wind-speed regions. The effectiveness of the proposed method is verified by simulation results for a 2-MW permanent-magnet synchronous generator (PMSG) wind turbine system, and experimental results for a reduced-scale PMSG wind turbine simulator.