IEC 61850 architecture
Andrea Bonetti - Product manager - relay
IEC 61850 is the new standard for substation automation that has been designed from the outset to be vendor independent, in order to achieve interoperability among protective devices (IEDs) from different manufacturers.
To help achieve these key objectives, IEC 61850 uses an architecture that incorporates abstracting. This essentially means that its data items and services are independent of the underlying protocols. The major benefit is that the abstract definitions can be mapped to any protocol that is capable of supporting the overall data and service requirements.
The formalization of the IEC 61850 mapping takes place in the XML-based Substation Configuration Language files, which will provide a convenient and efficient way of developing a formal description of the relationships between the automation system (Station HMI, vertical communication, reporting) and the equipments used in the substation (IEDs, horizontal communication, GOOSE messages).
The standard was published between 2002 and 2003, and several hundred substations are today in operation with the current version of the standard, but still the engineers dealing with it are called pioneers!
With the technical experience gained in the last years, several Technical Issues have been submitted. Today, the second version of the standard is being prepared.
The technical issues are expected to be cleared and some new applications will be introduced, not only related to substation automation. One very important concept that will probably be available in the new standard is the security aspect of the message traffic in the substation.
Based on my personal experience, where I have been involved in several projects with the IEC 61850 standard, one of the most delicate points of the standard is the testing procedure and the IEC 61850 tools that should be used to perform the 61850 engineering of the substation. Other issues, due to initial different interpretation of the standard by different vendors, have been mainly cleared today with cooperation among vendors.
Since the standard aims to achieve interoperability, this means that all the parties (relay manufacturers, SCADA manufacturers, customers and test equipment manufacturers) must cooperate in order to achieve it. Megger is currently working on an IEC 61850 interface that will soon be available. The interface will be compatible with all the new and old Megger MPRT and Programma FREJA test equipment.
Megger, represented by Programma in Sweden, is currently cooperating with STRI, the Swedish independent technology consulting company and accredited high voltage laboratory located in Ludvika, Sweden, for testing interoperability among protective devices from different vendors. For this purpose, one 4-day IEC 61850 training/workshop was held in Ludvika between the 25th and the 28th of November, 2008. For more information please visit the site www.STRI.se.
