Hybrid Sliding Mode Control of DFIG Wind Power Generation System Combining SMO and SMC

In light of the intrinsic nonlinear attributes and the indeterminate parameters associated with doubly fed induction motors (DFIG) within wind power generation systems (WPGS), proffering a methodology with the objective of attaining optimal power point tracking (MPPT) control becomes imperative. Henceforth, a Hybrid Sliding Mode Control (HSMC) strategy is posited as an innovative approach, tailored for the real-time synchronization of motor speed. This control paradigm amalgamates a sliding mode observer (SMO) harmoniously with a sliding mode controller (PEAL-SMC), the latter rooted in the power exponential convergence law (PEAL), giving rise to a composite framework denominated as Hybrid Sliding Mode Control (HSMC). Leveraging the capabilities of the sliding mode observer (SMO), we derive estimations for the stator current and rotor flux through an intricate analysis of the stator current and voltage parameters. Subsequently, employing these estimations, a computation is performed to ascertain the anticipated rotor speed. Transferring the ascertained rotor speed estimates into the realm of the PEAL-SMC, we seamlessly integrate them into the control tracking mechanism. The sliding mode controller, harnessing the power exponential convergence law (PEAL), is adept at augmenting the convergence speed of the system. This augmentation not only enhances the dynamic performance but also serves to diminish system jitter, thereby facilitating a more precise adherence to the reference speed. Via MATLAB/Simulink simulation, under step wind speed conditions, the proposed methodology not only guarantees the attainment of maximum power output but also exhibits a remarkable swiftness in convergence and commendable steady-state performance.