A novel improved variable-step-size P&O MPPT method and effective supervisory controller to extend optimal energy management in hybrid wind turbine

This paper describes a new maximum power point tracking (MPPT) based on a variable structure Automatic Systems approach in order to modify and improve the conventional method perturb and observe. Therefore, the main contribution of this work is related to the developments in advanced control and management system applied to hybrid wind turbines (WT). The objective is to strengthen the extraction capacity of wind power in order to obtain an extended operational range operating areas II and III. In other terms, the multi-objective optimization on hybrid WT based on sophisticate control system and robust management reliable to hybrid WTs is performed to design a perfect control system. This system requires a very complicated adaptation between the second-order sliding mode control (SOSMC)-based speed control, a novel MPPT technique modified enhanced perturb and observe MEPO, system limitation and system energy storage. In addition, to improve the quality of the electrical energy introduced into the grid, a new efficient and robust strategy control based on direct power control-space vector modulation (DPC-SVM-SOSMC) implemented in the network side of the converter is proposed. The feasibility and effectiveness of the proposed control system and the new switching algorithm that coordinates the control (the multi-objective optimization) are validated under entire operating range (II and III). The results have showed that, compared with the conventional control system, the proposed scheme provides higher power conversion efficiency, offers better grid power quality and has better dynamic performances as well as a very robust adaptation against the uncertainties of the parameters and external disturbances.