Grid-Forming Inverters (Slides)

This presentation will be a journey from a single microgrid to an integrated transmission & distribution system with 10,000+ inverters.
The presentation includes three parts. First, it will review the basic concepts of droop control and share the field experience on how CERTS Microgrid deals with overload events through autonomous control design. Second, it will provide a comparative study of two widely used grid-forming controls—single- and multi-loop droop controls. An insight will be provided to help understand the differences between the two widely used control strategies. EMT simulation, small signal analysis, and HIL testing will be provided to verify and explain this understanding. Finally, this presentation will share some simulation work performed on an integrated T&D co-simulation platform that has 10,000+ grid-forming and grid-following inverters leveraging the U.S. DOE invested open-source tools. The stability boundary identified through this case study will be discussed.