Grid Architecture: A Core Discipline for Grid Modernization

By the beginning of the present decade, it had become clear that efforts to improve U.S. electric power systems as well as power systems around the world were being stymied by a problem that was more or less recognized but not often articulated: the overwhelming complexity of what is generally and loosely referred to as the grid had become so great that understanding the implications of changes to the grid, or even determining what changes should be made, was significantly impeding grid modernization. Less obvious, but just as significant, changes to the grid were already occurring that increasingly diverged from the basic principles and assumptions under which the 20th century grid was developed. These changes could lead to severe consequences for grid reliability and functionality if they were not addressed. New developments are largely driven by evolving consumer expectations, the emergence of new technologies, and the change from central economies of scale to network economies. The latter is driven by increased penetration of distributed energy resources (DERs) connected at the distribution level ("the grid edge") and by ubiquitous communication connectivity. Additional drivers include deficiencies in resilience and increasing threat of cyberattack.