Grid-forming (GFM) technologies are being used to provide grid supporting functions in grid-connected mode. Among these desired functionalities, GFM converters must demonstrate a stable fault-ride-through (FRT) behavior, i.e., during and after a fault is cleared in the system. In this paper, a multi-dimensional adaptive inertia function for GFM converters is proposed to increase the critical clearing time while reducing the post-fault recovery/resynchronization time. The proposed technique is derived by analyzing the power-angle dynamics of the power synchronization loop. The efficacy of the proposed method is analyzed in MATLAB/Simulink EMT simulations using a virtual synchronous machine GFM controller as the benchmark control scheme and comparing it with a fully adaptive inertia/damping GFM controller. The full paper will present controller-hardware-in-the-loop simulations and experiments in a 3-inverter 10-kVA microgrid testbed.
