Synchronization stability and control strategies for PMSG-based wind energy systems under grid fault conditions

As wind power becomes more integrated into the global energy system, maintaining the stability and reliability of wind turbines during severe grid disturbances has become a challenge. This paper investigates the Synchronization instability of Permanent Magnet Synchronous Generator-based Wind Energy Conversion Systems during low voltage ride-through events. The research identifies key factors, such as grid impedance variations, DC voltage regulation, and active/reactive power imbalances, by analysing the dynamic mechanisms underlying the loss of Synchronization. A novel power compensation control strategy is proposed to ensure Synchronization stability by adapting the d-axis current reference to account for grid power losses. The simulation results show the proposed method’s superiority over conventional approaches of low voltage ride-through with better system stability and robustness against severe faults. A three-phase short circuit fault occurs at 0.4 s and is rectified at 2 s; within this interval, the frequency oscillations are not reduced with the conventional method; the proposed method suppresses the oscillations 20 % at 0.18 s and maintains the system in stable operation. Findings will thus serve as a basis for increasing the robustness of renewable energy systems in the face of future evolving grid code requirements. The entire analysis is performed with MATLAB/Simulink version R2023a.