Stable Maximum Power Extraction and DC Link Voltage Regulation for PMVG-Based WECS

Abstract

This study discusses the power maximization and dc-link voltage regulation problems of a permanent magnet vernier generator (PMVG)-based wind energy conversion system. To do this, first, the dynamical model of PMVG-based wind turbine is developed and presented. Then, the overall control structure is configured utilizing a back-to-back converter with a machine-side converter (MSC) and a grid-side converter (GSC). At this time, the sliding-mode control scheme with the modified enhanced exponential reaching law is proposed for both MSC and GSC control to achieve maximum power extraction and stable dc link voltage, respectively. Furthermore, the sliding manifold’s stability condition is derived using the Lyapunov function, which guarantees a better transient performance and tracking accuracy. Finally, the proposed control scheme’s superiority and efficiency are demonstrated using theoretical simulations on 5 kW PMVG-based and 1.5 MW permanent magnet synchronous generator-based wind turbine systems and empirical findings derived from a grid-connected 5 kW PMVG-based wind turbine in the experimental setup.