Short-Circuit Analysis of Inverter-Based Distributed Generation and Energy Storage System With Different Control Modes

The increasing integration of inverter-based distributed generation (DG) and battery energy storage systems (BESS) in modern power systems is driven by the demand for cleaner and more reliable energy sources. However, the diverse control strategies used in these inverter-based resources present challenges in accurately modeling fault current behavior. These challenges can lead to malfunctions in protection systems and increase the risk of damage to power electronic converters. This paper analyzes the fault current characteristics of inverter-based DG and BESS under balanced, unbalanced, and high-impedance fault conditions. Four control modes are considered: maximum power point tracking, PQ, VQ, and Pf. A fault current estimation method is proposed using the initial and final value theorems to evaluate system response during both transient and steady-state periods. The proposed approach is validated through detailed MATLAB/Simulink simulations and further verified using a power hardware-in-the-loop setup. Results confirm that the method accurately captures the dynamic behavior of inverter-based resources under various fault scenarios, providing insights for improved protection coordination in power electronic-rich networks.