IEC 61850 Digital Substation Design Tutorial for Novices

A substation protection and control system based on the concepts of IEC 61850 can be built faster, more efficiently, and more repeatably by replacing physical wiring with digital communications. For a utility, it means replacing easily understood and easily learned wiring with the complexity of data modeling, data flows, and communications networks. This involves learning & understanding several standards. These standards mainly include IEC 61850, IEEE 1588 v2, IEC 62439-3, and IEC 61869. Most of these standards have multiple parts, editions and revisions. For example, IEC 61850 consists of ten main parts with several other associated parts still being edited and added. IEEE 1588 has multiple profiles applicable to the power utility sector and so on. Hence, the research and design can be quite intimidating and discouraging for a new user to go through all of these before starting a project. National Grid is actively working on their first substation with a fully digital protection and control system and has had to develop the knowledge and understanding necessary to support this project. This paper describes the step by step approach used by National Grid for designing the architecture, selecting different components, and testing the system for a fully digital substation project. The paper answers questions like where do we start? What redundancy protocol to use? What time synchronization profile to use? By describing the process National Grid has worked through, this paper is intended to be used as a foundation for other utilities to approach IEC 61850-based digital substation design.