Design and Performance Assessment of a Virtualized IED for Digital Substations

Digital substations have significantly enhanced power grid protection by replacing traditional copper wiring with fiber-optic communication and integrating IEC 61850-compliant Intelligent Electronic Devices (IEDs), resulting in greater efficiency, reliability, and interoperability. While these advancements provide improved interoperability, challenges such as high costs, complex networks, and limited upgrade-ability persist. To mitigate these issues, the virtualization of IEDs has emerged as a cost-effective solution, offering scalability, simplified maintenance, and reduced hardware costs by replacing traditional hardware-based IEDs with software-based counterparts. However, the performance and reliability of virtual IEDs (vIED) must be rigorously evaluated to ensure their robustness in real-time applications. This paper develops, implements, and evaluates a vIED designed to match the performance of its hardware-based counterparts. The vIED was deployed on a server using virtual machines, with its core logic implemented in low-level programming languages to ensure high-speed, deterministic behavior. The performance was evaluated using real-time simulations, focusing on the response times of the protection functions. The results demonstrated that the vIEDs achieved acceptable response times, validating their suitability for deployment in critical time-sensitive environments within digital substations.