# IEC 61850

IEC 61850 is an international standard defining communication protocols for intelligent electronic devices at electrical substations. It is a part of the International Electrotechnical Commission's (IEC) Technical Committee 57 reference architecture for electric power systems. The abstract data models defined in IEC 61850 can be mapped to a number of protocols. Current mappings in the standard are to Manufacturing Message Specification (MMS), GOOSE (Generic Object Oriented System Event) [see section 3, Terms and definitions, term 3.65 on page 14], SV (Sampled Values) or SMV (Sampled Measure Values), and so on to web services. In the previous version of the standard, GOOSE stood for "Generic Object Oriented Substation Event", but this old definition is still very common in IEC 61850 documentation. These protocols can run over TCP/IP networks or substation LANs using high speed switched Ethernet to obtain the necessary response times below four milliseconds for protective relaying.

## Standard documents

IEC 61850 consists of the following parts:
* IEC TR 61850-1:2013 – Introduction and overview
* IEC TS 61850-2:2003 – Glossary
* IEC 61850-3:2013 – General requirements
* IEC 61850-4:2011 – System and project management
* IEC 61850-5:2013 – Communication requirements for functions and device models
* IEC 61850-6:2009 – Configuration language for communication in electrical substations related to IEDs
* IEC 61850-7-1:2011 – Basic communication structure – Principles and models
* IEC 61850-7-2:2010 – Basic communication structure – Abstract communication service interface (ACSI)
* IEC 61850-7-3:2010 – Basic communication structure – Common Data Classes
* IEC 61850-7-4:2010 – Basic communication structure – Compatible logical node classes and data classes
* IEC 61850-7-410:2012 – Basic communication structure – Hydroelectric power plants – Communication for monitoring and control
* IEC 61850-7-420:2009 – Basic communication structure – Distributed energy resources logical nodes
* IEC TR 61850-7-510:2012 – Basic communication structure – Hydroelectric power plants – Modelling concepts and guidelines
* IEC 61850-8-1:2011 – Specific communication service mapping (SCSM) – Mappings to MMS (ISO 9506-1 and ISO 9506-2) and to ISO/IEC 8802-3
* IEC 61850-9-2:2011 – Specific communication service mapping (SCSM) – Sampled values over ISO/IEC 8802-3
* IEC/IEEE 61850-9-3:2016 – Precision Time Protocol profile for power utility automation
* IEC 61850-10:2012 – Conformance testing
* IEC TS 61850-80-1:2016 – Guideline to exchanging information from a CDC-based data model using IEC 60870-5-101 or IEC 60870-5-104
* IEC TR 61850-80-3:2015 – Mapping to web protocols – Requirements and technical choices
* IEC TS 61850-80-4:2016 – Translation from the COSEM object model (IEC 62056) to the IEC 61850 data model
* IEC TR 61850-90-1:2010 – Use of IEC 61850 for the communication between substations
* IEC TR 61850-90-2:2016 – Using IEC 61850 for communication between substations and control centres
* IEC TR 61850-90-3:2016 – Using IEC 61850 for condition monitoring diagnosis and analysis
* IEC TR 61850-90-4:2013 – Network engineering guidelines
* IEC TR 61850-90-5:2012 – Use of IEC 61850 to transmit synchrophasor information according to IEEE C37.118
* IEC TR 61850-90-7:2013 – Object models for power converters in distributed energy resources (DER) systems
* IEC TR 61850-90-8:2016 – Object model for E-mobility
* IEC TR 61850-90-12:2015 – Wide area network engineering guidelines

## Features

IEC 61850 features include:
* Data modelling – Primary process objects as well as protection and control functionality in the substation is modelled into different standard logical nodes which can be grouped under different logical devices. There are logical nodes for data/functions related to the logical device (LLN0) and physical device (LPHD).
* Reporting schemes – There are various reporting schemes (BRCB & URCB) for reporting data from server through a server-client relationship which can be triggered based on pre-defined trigger conditions.
* Fast transfer of events – Generic Substation Events (GSE) are defined for fast transfer of event data for a peer-to-peer communication mode. This is again subdivided into GOOSE & GSSE.
* Setting groups – The setting group control Blocks (SGCB) are defined to handle the setting groups so that user can switch to any active group according to the requirement.
* Sampled data transfer – Schemes are also defined to handle transfer of sampled values using Sampled Value Control blocks (SVCB)
* Commands – Various command types are also supported by IEC 61850 which include direct & select before operate (SBO) commands with normal and enhanced securities.
* Data storage – Substation Configuration Language (SCL) is defined for complete storage of configured data of the substation in a specific format.