The FREEDM architecture is categorized into four levels based on the complexity of the system design and operation
Level 1: Energy Cell (DC Microgrid)
Coordination of local load, generation, and storage on SST secondary for maintaining instantaneous power balance.
Level 2: Single SST
Interaction of a single SST with medium-voltage FREEDM system based on localized measurements and control.
Level 3: FREEDM System
Interaction of multiple SSTs and FIDs within a single FREEDM system based on peer to peer communications and distributed control. Note “1 MVA SST” corresponds to Substation SST.
Level 4: Multiple FREEDM Systems
Interaction of multiple FREEDM systems interconnected to form a medium-voltage distribution system.