Asymptotic Tracking Stability Control Method for Grid-Connected Wind Turbine Systems Based on Quantitative Trajectory Constraints

To address the issue of instability induced by direct-drive wind turbines connected to weak AC grids, a grid-connected asymptotic tracking stabilization control strategy for direct-drive wind turbines based on quantitative trajectory constraints is proposed. First, an equivalent mathematical model of the direct-drive wind turbine unit is established, with the dq-axis coupling caused by unmodeled dynamics, power fluctuations, and operational mode switching regarded as inherent disturbances of the system, thereby enhancing modeling accuracy. Secondly, a grid-connected asymptotic tracking stabilization control method for wind turbines based on quantitative trajectory constraints is proposed. This method ensures transient response trajectory constraints throughout the process while guaranteeing steady-state tracking ability and robust operation of the overall system, ensuring that the entire transient response trajectory remains within the specified constraint range, thereby improving the stable operation of the wind turbine grid-connected system. Finally, a simulation model is built in PSCAD for comparative validation. The simulation results demonstrate that the proposed control strategy enhances the dynamic performance of the full transient response trajectory, effectively improving the stable operation capability of the overall system.