Speed sensor-less and robust power control of grid-connected wind turbine driven doubly fed induction generators based on flux orientation

The aim of this paper is to propose a power control method for Wind Energy Conversion System (WECS) using Double Fed Induction Generator (DFIG). This control strategy, based on stator flux orientation, tracks the maximum power for different wind speeds and regulates separately the active and reactive powers exchanged between the generator and the grid. The control algorithm uses Sliding Mode Control technique (SMC). The suitability of the proposed control strategy is proved in terms of efficiency maximization by including external disturbances (grid fault condition) with respect to bounded parameter variations affecting the electrical system. The estimation of the speed is based on Model Reference Adaptive System (MRAS) method. Some results of simulation are presented, discussed to prove efficiency and robustness of the DFIG control policy for WECS against external and internal perturbations with MPPT responses