Grid-Forming Control for Edge-Based Ders: Integration Strategies and Performance in Weak Grids

The integration of inverter-based Distributed Energy Resources (DERs) into weak grids presents stability challenges due to low inertia and high impedance, leading to voltage and frequency fluctuations. To enhance system resilience, GridForming (GFM) and Grid-Following (GFL) inverters are used together, ensuring effective voltage and frequency regulation. GFM inverters emulate traditional synchronous generators, providing grid stability, while GFL inverters optimize power exchange using phase-locked loop (PLL) synchronization. This study analyzes the performance of DERs in the IEEE-15 bus radial distribution network under steady-state and transient conditions. A key aspect is the seamless transition of an islanded microgrid to grid-connected mode, which is crucial for maintaining reliability during grid disturbances or planned islanding. The case study is implemented in MATLAB/SIMULINK using <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$m$</tex>-file scripts for system modeling and control. The transient analysis evaluates the impact of inverter control strategies on the stability, voltage regulation, and frequency response of the microgrid. The results provide insights into improving the integration of DER, improving power quality, and ensuring robust operation in weak grids. This research contributes to the development of advanced inverter control techniques that support the stable and efficient operation of modern distribution networks with high DER penetration.