Fault Ride-Through Control Strategy for Grid-Forming Inverters Based on Dynamic Virtual Angular Velocity Regulation

[Objective] The large-scale integration of inverter-based renewable generation introduces new challenges for power-system stability. Although virtual synchronous generator（VSG）control imparts virtual inertia and damping，grid short-circuit faults can induce excessive currents that threaten synchronization and may cause inverter disconnection. This paper proposes a VSG fault ride-through strategy based on dynamic virtual velocity regulation. [Methods] The transient behavior of the VSG under fault conditions is analyzed to identify the source of overcurrent，and dynamic virtual angular velocity regulation is introduced to maintain power-angle stability. The reactive-power control loop is reinforced to improve reactive-power compensation，and a voltage-current dual-loop structure based on the balanced-current method is employed to ensure balanced three-phase output currents. [Conclusions] Matlab/Simulink simulations show that，during grid short-circuit faults，the virtual angular velocity and power angle stay close to their rated values； short-circuit current is limited to within 1.5 times the VSG’s rated current； the VSG provides reactive power in accordance with national grid connection codes； output currents remain three-phase balanced； and fault impact currents are effectively suppressed. [Conclusions] Compared with existing methods，the proposed strategy more effectively stabilizes virtual angular velocity and power angle，limits short-circuit and fault impact currents，accelerates transient response，maintains balanced three-phase outputs，and ensures secure，stable VSG operation under grid short-circuit conditions.