by Tom Berry, Schneider-Electric
IEC TC 57 WG 17 is in charge of power system intelligent electronic device communication and associated data models for microgrids, distributed energy resources and distribution automation.
IEC 61850 is a large set of documents that is challenging to review and keep consistent. This has led to the development of a technical issue “Tissue” reporting process for managing errors, omissions and ambiguities in the various documents standard which are likely to cause interoperability problems. This has allowed issues and their solutions to be documented and discussed more rapidly than the conventional IEC processes for creating documents for technical corrigenda, amendments and new editions.
For the main parts of IEC 61850, a list of Tissues is published every six months that gives a list of tissues that have been resolved and hence should be applied by manufacturers and test houses. In addition, there is a release of the corresponding machine-readable code components (“NSD” files).
Since the publication of IEC 61850-7-420 Edition 2 in 2011, only a few issues have been reported. Part 7-420 has a wider reader base than for substation automation, so in addition to the NSD files, IEC TC 57 WG17 is planning to publish a conventional corrigendum document that will describe the changes for clarifications and corrections.
There are a few technical changes to better follow the naming convention for data objects. In the short-term this requires a little work to replace deprecated names, but the naming convention makes it easier for implementers to navigate the data model. Several editorial issues were addressed by updating the descriptions of the relevant data objects. This included simple corrections for the names of logical nodes SBAT and SINV for supervising batteries and inverters respectively. These changes were made in the master data model and are shown in the corrigendum document as changes in the relevant tables.
Some tissues required more extensive documentation as they describe application aspects of the data models. More text and a new diagram will clarify the variables that show the availability of reactive power. A new annex clause and table is proposed with details of the correspondence for data objects where a set of DGEN, DLOD, DSTO logical nodes provide different views of the same resource.
Updates have also been made for the data models for large generators, with the publication of a new edition of IEC 61850-7-410. This part describes data models for hydroelectric power plants, steam and gas turbines, particularly the interfaces seen in plant control centers.
This edition has adopted a modelling approach that aims to share common concepts for the different generation domains and to increase the modularity to make it easier to extend in the future. This includes layered architecture for the power station model, in accordance with the control hierarchy concepts defined in IEC 60050-351-55; a comprehensive review of the models considering the approach outlined in IEC 61850-7-420:2021, aimed at harmonizing fundamental concepts in the power generation domain; and a systematic alignment with the concepts outlined in IEC 61850-7-500:2017. The new edition also provides clarifications on the purposes and intended use of such information model in a new set of explanatory clauses.
Biography:
Tom Berry studied Electrical Engineering at Bath University, UK. For the last 25 years he has worked for Schneider Electric in the UK and France.
Tom has worked on control center projects integrating SCADA systems within dispatch training simulators, transmission and distribution network management systems. He now works “closer to the edge” as a software architect for feeder automation RTUs. He is a member of several IEC TC57 WGs and the editor of IEC TS 62361-102 technical report on CIM-61850 harmonization.
