Time-based adaptive second order sliding mode controller for wind energy conversion optimization

In this paper a novel time-based adaptive second-order sliding mode (SOSM) technique to optimise the efficiency of a variable-speed wind turbine is developed and analised. A revisited form of a recent time-based adaptation algorithm is proposed to deal with the characteristics and control requirements of the wind energy conversion system (WECS), particularly fastly varying disturbances due to gusty wind effects. The revisited algorithm, which enhances the reactivity of the adaptation strategy against fastly varying uncertainties, represents the main theoretical novelty of this work. The proposed controller is extensively assessed through computer simulation of the WECS under study.