Online Set Point Adjustment for Trajectory Shaping in Microgrid Applications

This paper proposes and evaluates a strategy to mitigate the transients of an apparatus, e.g., an electronically-interfaced distributed energy resource (DER) unit. This strategy is based on response monitoring and can be implemented based on either set point automatic adjustment (SPAA) or set point automatic adjustment with correction-enabled (SPAACE). SPAA takes advantage of an approximate model of the system to calculate the intermediate set points. SPAACE monitors the trajectory of the variable of interest and bases its decisions on the trend of variations of that variable and accounts for the inaccuracies and unmodeled dynamics by switching the command input between alternative set points. Case studies are presented to demonstrate the application and effectiveness of the proposed strategy in limiting voltage or current excursions in balanced and unbalanced microgrid study systems, subsequent to a step change in set point, load switching, and black start.