Practical applications of Ethernet in substations and industrial facilities

This paper is a tutorial in Ethernet communications and architectures. The defacto LAN standard throughout the world is Ethernet and the worldwide investment into this technology dwarfs that of investment into any other LAN standard. Speed, fiber support, multiple services and protocol support, and the emergence and usage of the IEC61850 protocol have resulted in an increase in the installation of Ethernet within substations and industrial facilities. There are many practical aspects associated with the application of Ethernet within the substation and industrial facility. This paper will address Ethernet fundamentals and will attempt to cover the most common elements of an Ethernet architecture from media selection, requirements for protective relaying systems, managed Ethernet Switch functions and terminology relevant to the protection relay engineer (such as VLAN, RSTP and QoS), network topology (ring, star, mesh, redundancy) and high speed recovery of redundant ring networks. Architectures for different applications will be reviewed, such as SCADA and GOOSE messaging. The intent of this paper is to educate the non-IT person, such as the protective relay engineer, on Ethernet fundamentals that are important to protective relaying applications.