Y. Lin, J. Eto, B. Johnson, J. Flicker, R. Lasseter, H. Villegas Pico, G. Seo, B. Pierre, and A. Ellis. 2020. Research Roadmap on Grid-
Forming Inverters. Golden, CO: National Renewable Energy Laboratory. NREL/TP-5D00-73476.
https://www.nrel.gov/docs/fy21osti/73476.pdf
someone should archive nrel
