Modeling and Control of a Multi‐Energy Microgrid With Wind LVRT and Battery Pre‐Synchronization Strategy

ABSTRACT To achieve the “dual carbon” goals, modern power systems must integrate large‐scale renewable energy, whose inherent intermittency poses challenges to grid stability. Multi‐energy microgrids combining wind, photovoltaic (PV), and energy storage systems provide an effective solution but still face issues in coordinated control, fault ride‐through, and seamless grid transitions. This paper develops a hybrid microgrid model comprising a Doubly Fed Induction Generator (DFIG), a PV array, and a battery energy storage system, and proposes a coordinated control framework. The DFIG employs its grid‐side converter (GSC) to regulate DC bus voltage and its rotor‐side converter (RSC) for maximum power point tracking (MPPT). The PV inverter similarly employs MPPT control, while the battery operates in constant power mode under grid‐connected conditions and in droop control under islanded conditions. To enhance the Low Voltage Ride‐Through (LVRT) capability, a flexible crowbar strategy based on rotor current, voltage sag depth, and DC bus voltage is proposed. Additionally, a pre‐synchronization module based on voltage magnitude and phase angle is integrated with the battery control to ensure smooth transitions between islanded and grid‐connected modes. Simulation studies conducted in MATLAB/Simulink show that the proposed flexible crowbar achieves the largest reduction among the three stator currents (from 1.25 pu to 1.01 pu, 19.2%) and among the three rotor currents (from 2.0 pu to 1.46 pu, 27%), effectively suppressing fault currents and improving equipment safety. The pre‐synchronization scheme further enables seamless reconnection of the microgrid to the main grid, while sensitivity analyses of the voltage‐ and angle‐loop control gains confirm the robustness and adaptability of the proposed strategy during mode transitions.