A Multi-Objective Coordinated Fault-Riding Strategy for Grid-Forming Converters

To address the issues of excessive fault current, insufficient voltage support, and frequency oscillations in grid-forming converters during power grid short-circuit faults, this paper establishes a fault ride-through test model based on the principle of impedance voltage division and analyzes the fault transient characteristics of a virtual synchronous generator (VSG). A fault voltage regulation strategy that integrates reactive power injection and compensation switching is proposed, and an active power regulation method based on current-limiting constraints is proposed. An adaptive inertia-damping mechanism is introduced into the control loop, which dynamically regulates the virtual inertia and virtual damping coefficients to suppress frequency fluctuations during fault engagement and clearance. The rationality of the system parameter configuration is verified through impedance modeling, and experimental validation is conducted using the RT LAB semi-physical platform. The results show that the proposed multi-objective collaborative control strategy enables the converter to operate without disconnecting from the grid during grid faults. The steady-state fault current meets the limit requirements, the frequency response is stable, and reactive power support complies with the GB/T 29319-2024 national standard. This study provides theoretical support for fault ride-through of grid-forming converters in power systems with a high proportion of power electronics.