The deployment of inverter-based resources (IBRs) in modern grids has increased to integrate renewable energy. However, most IBRs today are grid-following, posing stability concerns due to their dependency on a stiff grid. It has increased the attention to grid-forming (GFM) inverters, which can generate internal voltage reference, elucidating the pathway to IBR-dominated grids. However, transitioning to IBR-dominated grids with GFM inverters remains challenging due to limited understanding of their roles in stabilizing low-inertia grids, particularly regarding the stability during grid disturbances. Inverters have stringent overcurrent limits due to hardware constraints, necessitating current limiting control. On the other hand, in current limiting, inverters are prone to instability as they cannot supply the required power, urging frequency stabilization methods. However, the interactions between them need further understanding. This paper proposes an equivalent impedance model to analyze these interactions and their impact on inverter transient stability. The model is validated through numerical simulations and experimental results, demonstrating its accuracy and effectiveness.
