Area aggregation of network systems

A physically motivated reduction of "network" systems which are encountered in power systems, economics and circuits, etc., is considered. The technique is to aggregate the states in an area of the system into the center of inertia variable. Aggregability conditions are examined in terms of the structure and dynamics of the systems. The resulting aggregate model also has the network system structure. Near-aggregability and time-scales separations are investigated when the aggregability conditions are only approximately satisfied.