Nonlinear Control of Variable Speed Wind Turbines via Fuzzy Techniques

In this paper, a fuzzy logic controller is proposed to fulfill the objective of maximum power extraction based on a two-mass model. One of the crucial problems is that the effective wind speed cannot be measured directly due to the high disturbance of the wind speed and the high cost of sensors. Three algorithms are used to estimate the effective wind speed by solving power balance equations, and the estimated wind speed is used to determine the optimal speed reference for a generator control system. The control performance of the fuzzy logic controller is verified in the whole system and compared with a conventional PI controller. Simulation results are presented to illustrate the effectiveness and robustness against parameter variations of the proposed control design.