Abstract

The fundamental and complex transformation of traditional power grids into Smart Grids highlights challenges such as aging infrastructure, maintaining reliability and security, and integrating distributed energy resources. A core challenge is poor interoperability, which can lead to major disruptions, as evidenced by blackouts in Chile and Spain, where communication and control system failures critically delayed restoration and led to cascading failures. Thus, achieving reliable, secure, and standardized interoperability is crucial for grid resilience, data-driven services, and cross-border energy cooperation. This paper presents a structured analytical review of interoperability in Smart Grids, exploring three key areas: Smart Grid Architectures, deployment of IEC 61850, and the integration of Real-Time Ethernet and Internet of Things technologies, reviewing their main requirements across cyber-physical layers, operational domains, and stakeholder roles. This review provides a more comprehensive understanding of how important interoperability in current smart grids is and how it can be more easily achieved with the application of IEC 61850, while also discussing how to integrate the standard with different Smart Grid Architectures to better capitalize on the advantages of each one of these architectures. The results demonstrate that the isolated adoption of IEC 61850 is insufficient to guarantee full interoperability, as its multiple implementation options may lead to vendor-specific incompatibilities; identifies Interoperability Profiles as a practical mechanism to reduce implementation ambiguities and enhance standardization; and establishes gateways acting as middleware as critical enablers for protocol translation, data synchronization, and cross-layer integration, directly contributing to enhanced Smart Grid resilience and mitigation of large-scale systemic failures.