Implementation of third-order sliding mode for power control and maximum power point tracking in DFIG-based wind energy systems

Abstract

In the field of generation systems, system performance, and power quality are greatly affected by traditional control techniques based on proportional-integral (PI) controllers, which are affected by internal and external factors. Wind power conversion systems based on doubly-fed induction generators are exposed to certain nonlinearities, uncertainties, and external disturbances. From another side, the extraction of the mechanical wind energy required a high-performance control system. This study proposes a robust nonlinear chattering-free third-order sliding mode control (TOSMC) based power control applied to fix its primary disadvantages which are the chattering phenomena and active and reactive power ripples. To show the potential of the proposed TOSMC control, a comparison study considering the TOSMC control, traditional sliding mode control, and the other existing controls is done in terms of power ripples, harmonic distortion of stator current, robustness, and response time. To ensure maximum power extractions and to protect the system, the maximum point power tracking technique based on TOSMC and the proposed control are also implemented. In addition, These techniques are used to control the stator powers. Finally, simulations (using Matlab software) are performed using different wind speeds with durability testing. The simulated results show that the proposed TOSMC control with the MPPT-TOSMC technique in this paper achieves satisfactory results in terms of reducing power ripples, response time, and harmonic distortion of stator current compared to the sliding mode control, where the harmonic distortion reduction ratio of the current was (50.24%) and the active power ripple reduction ratio (47.50%) and the reactive power (46.68%).