Abstract：In grid-forming converters with weak overcurrent capability, it is generally necessary to introduce the current limiter to ensure fault current limiting. However, the synchronization stability of the system is weakened after triggering the current limiter, which is seldom comprehensively considered and addressed in existing studies. To this end, the phasor diagram method is used to reveal the fault current characteristics in this paper. Then, the adverse impact of the current limiter on the synchronization stability of the converter is analyzed based on the power angle characteristic curves and the extended equal area criterion. Thus, a virtual inertia current limiting method for grid-forming converters with enhanced synchronous stability is proposed, which simultaneously solves the fault current limiting and synchronous stability problems of converters by quantitatively controlling the virtual inertia. Finally, the correctness of the theoretical analysis and the effectiveness of the proposed method are verified by Matlab/Simulink simulation experiments.
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2025, Vol. 26 
