Communication and Intelligent Technologies Enabling the Evolution of Smart Grids: From Unidirectional Power Systems to Autonomous Bidirectional Networks

The transition from conventional power systems to Smart Grids is driven by the increasing penetration of distributed energy resources (DERs), battery energy storage systems (BESS), electric vehicles (EVs), and power-electronic interfaces, together with growing requirements for flexibility, reliability, resilience, and efficiency. This transformation requires more than infrastructure digitalization: it depends on the coordinated development of communication, digital information, analytical, and operational capabilities. This paper reviews these technological layers and discusses how their integration enables the evolution from unidirectional and weakly observable networks toward bidirectional, adaptive, and increasingly autonomous power systems. Communication technologies are examined across wide-, field-, neighborhood-, and home-area networks, while intelligent technologies include state estimation, forecasting, optimization, artificial intelligence, machine learning, digital twins, ADMS, and DERMS. A capability-driven framework relates these technologies to successive grid generations. The analysis indicates that autonomy emerges from functional integration, with communications enabling connectivity, digital infrastructures providing observability, analytical methods supporting situational understanding and prediction, and operational platforms enabling coordinated decision-making and control.