An Overview of Industry-related Grid Forming Inverter Controls

The potential of weak grid scenarios resulting from increased penetration of inverter-based resources (IBRs) and gradual retirement of synchronous generators (SGs) has drawn much attention to the research and implementation of various inverter control strategies. This paper presents an overview of key industry-related grid-forming (GFM) inverter control technologies, summarizing their strengths and weaknesses for grid-interactive operations under several operating conditions. This investigation also addresses the conceptual distinction between GFM and grid-following (GFL) inverters, highlighting the need for GFM inverter technologies to provide grid support functions, especially in weak grid areas. Theoretical analyses are validated through simulation models built under various operating modes of load variations and unexpected phase interruptions to verify the ability of GFM technology to contribute to grid strength in the absence of SGs. When analyzed, the results suggest that GFM technology can achieve desirable grid stability and reliability efficiency even in the absence of SGs.