Gain-Scheduled Linear Parameter-Varying Control with Aerodynamic Torque Observation for PMSG in WTCS

Abstract

This study proposes a gain-scheduled linear parameter-varying (LPV) control strategy for rotor speed regulation of a permanent magnet synchronous generator (PMSG) in wind turbine conversion systems (WTCS). The nonlinear electromechanical dynamics are reformulated into a speed-dependent LPV model over the operating region. To support reference generation without direct aerodynamic torque measurement, a first-order aerodynamic torque observer is introduced. Based on a set of local linear quadratic regulators designed at selected operating points, a smooth gain-scheduling law is constructed through a neural-network-based convex interpolation mechanism. The resulting controller preserves continuity across operating conditions and improves dynamic response compared with a conventional PI-PI strategy. Closed-loop stability is discussed using a common Lyapunov theory for the local closed-loop models, and simulation studies under nominal and parameter-perturbed conditions are carried out to evaluate the proposed method. The simulation results indicate that the proposed strategy can provide satisfactory performance.