Integral sliding mode control for increasing maximum power extraction efficiency of variable-speed wind energy system

Abstract

Maximum wind energy extraction remains a challenge for large-scale wind turbines due to their higher moment of inertia. In this respect, this study investigates the challenges of achieving a maximum power extraction facility from the variable speed wind turbine (VSWT) by using a sliding mode control (SMC) scheme. Firstly, a integral sliding manifold is designed to achieve maximum power extraction and reduce mechanical loads in large-scale wind turbines (WTs). Secondly, the sliding manifold’s reachability condition is derived based on the Lyapunov function, which guarantees the fast convergence rate of the error dynamics in-finite time. Further, the proposed control scheme in this study produces the efficient chatter-free electromagnetic torque reference to the generator by holding the blade pitch angle at zero. Specifically, the proposed approach can lead to better performance meanwhile reaching the maximum power capture from below rated wind speed. Finally, we demonstrate the feasibility and efficacy of the proposed method through a widely-recognized benchmark model of WT using MATLAB/SIMULINK.