Operating-Point-Parameterized State-Space Models of Black-Boxed Grid-Following Inverters for Maximum Transferable Active Power Prediction

This letter introduces an efficient method for analytically predicting the maximum transferable active power (MTAP) of a grid-following inverter (GFLI), considered as a black box, under any arbitrary short circuit ratio (SCR), X/R ratio, and reactive power injection level. By measuring the GFLI’s admittance at several different operating points, an operating-point-parameterized state-space model (OPP SSM) is developed and exploited to predict the MTAP. The proposed method obviates the need for repetitive electromagnetic transient time-domain simulations or frequencydomain impedance criteria by gradually increasing active power output until the MTAP is reached. The feasibility of the synthesized OPP SSM for MTAP prediction has been experimentally validated on a power-controlled GFLI, demonstrating its potential for aiding the integration of inverter-based resources in modern power systems.