A dynamic state estimation based sliding mode controller for wind energy generation system connected to multimachine grids

This paper proposes a sliding mode control scheme suitable for designing controllers in general nonlinear systems. To improve its performance, a chattering mitigation strategy is also proposed, which is proven to be capable of effectively alleviating the oscillations generated by the original sliding mode controller. For the validation of the functionality of the proposed control scheme in a nonlinear system, a sensorless doubly fed induction generator wind energy generation system connected to a multimachine system is used in the case study. Dynamic state estimation is required for sensorless doubly fed induction generator wind turbine as the internal state, rotor speed, which is used to construct the control scheme is not directly available. In order to do that, a unscented Kalman filter algorithm based dynamic state estimator is designed. The success of using proposed dynamic state estimation-based sliding mode control strategy to regulate the dynamical behavior of a wind energy system broadens the ken of the field of control methodology as well as the field of power systems.