Grid Forming Inverter Modeling for Microgrid Studies in Distribution Systems.

Electric power systems have been designed and operated for decades considering the physical properties and control responses of large synchronous generators. However, nowadays power grids are rapidly transitioning towards increasing the amount of non-traditional energy sources such as energy storage, variable generation (wind, solar PV), among others. These inverter-based resources provide multiple ancillary services for grid support using control methods such as grid forming inverters, which can be used for enabling intentional and unintentional islanded areas within a power system. This paper presents the advancement in modeling inverter-based resources within EPRI’s OpenDSS open-source simulator for supporting grid forming inverter control mode. This new functionality enables engineers and researchers to extend existing functionalities, particularly in distribution power system analysis and design, including microgrids.