Microgrid islanding and grid restoration with off-the-shelf utility protection equipment

Abstract

Automatic islanding and reconnection are commonly required at the point of common coupling between microgrids and macrogrids. Islanding systems open the point of common coupling during short circuits, open circuits, and dangerous backfeed conditions in the macrogrid. Automatic synchronizing systems provide reconnection by dispatching multiple distributed energy resources to reduce slip and voltage differences at the point of common coupling. This paper explains how commercial, off-the-shelf protective relays can be used to automatically island microgrids from and reconnect microgrids to the macrogrid.