What types of microgrids are there

The Microgrid Exchange Group defines a microgrid as ‘‘a group of interconnected loads and distributed energy resources within clearly defined electrical boundaries that acts as a single controllable entity with respect to the grid. A microgrid can connect and disconnect from the grid to enable it to operate in both grid-connected or island-mode.’’ There are two categories of microgrids, off-grid and grid-connected and each encompass many different setups. [pdf]
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