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The current study proposed a robust sensor-less sliding mode second-order based on a super twisting algorithm (STA-SMSO) approach using a new observer Model Reference Adaptive System-Adaptative Neuro-Fuzzy Inference System (MRAS-ANFIS). This model was applied to a doubly fed induction generator (DFIG) wind turbine running under variable wind speed and DFIG fed with a power voltage source without a speed sensor, while the control objective was used to regulate independently, the active and reactive power DFIG stator were decoupled by using the field-oriented control technique. Additionally, this process reduced the cost of the control scheme and the size of DFIG by eliminating the speed sensor (encoder). In order to improve the traditional MRAS, the MRAS-ANFIS observer was proposed to replace the usual PI controller in the adaptation mechanism of MRAS with an Adaptative Neuro-Fuzzy Inference System (ANFIS) controller. The estimation of rotor position was tested and discussed under varying load conditions in low, zero, and high-speed region. The results mentioned that the proposed observer (MRAS-ANFIS) presented an attractive feature, such as guarantees finite time convergence, good response on speed wind variations, high robustness against machine parameter variations, and load variations compared to the conventional MRAS observer and MRAS-Fuzzy. Hence, the estimated rotor speed converged to their actual value has the capacity for estimating position in deferent region (low/zero/high) of speed. [ABSTRACT FROM AUTHOR]

Currently, both the permanent magnet synchronous generators and the electrically excited synchronous generator are used in the direct-drive wind turbine technology to produce electrical energy. Aiming at the high cost of permanent magnets, the commercial availability, mainly in African, and the difficulty of the magnetic field weakening operation of the PMSG machine, the work studied a novel design of a direct-drive H-Darrieus wind turbine (H-DWT) based on doubly fed induction generator (DFIG) using MATLAB/Simulink software. The stator topology is connected directly to the grid while the rotor is connected to grid with back to back converters. The study includes the sizing, modeling, and control of the proposed system. A sliding mode control (SMC) approach is selected in order to achieve robust control of active/reactive power injected into the grid. The real wind speed spanning a period of one year of the province of Adrar city located in the south of Algeria is used to test the complete system. The simulation results illustrate the operating efficiency of a DFIG and the performance of the SMC method in stator powers tracking in direct-drive wind energy conversion systems. • The design of the direct-drive vertical axis wind turbine system is realized through a well detailed dimensioning. • A detailed modeling of DFIG under fewer hypotheses is introduced. • Sliding-mode control approach is designed for Stator power regulation of DFIG. • The proposed SMC presented the best performance. [ABSTRACT FROM AUTHOR]