No power without communication

Communication between equipment and systems is increasingly important for electric power grids

By Morand Fachot

A transition from one-way power distribution structures to two-way grids, where information is exchanged in both directions between producers and consumers, is taking place. This change to Smart Grids requires the incorporation of interoperable equipment and systems for controlling the electric power process into integrated systems and solutions. IEC Technical Committee (TC) 57: Power system management and associated information exchange, develops International Standards that are critical to this integration.

Overhead power lines
IEC TC 57 develops Standards for the transmission of data through power lines

Evolving role over 50 years

IEC TC 57 was established in 1964 to meet an urgent need to produce International Standards in the field of communications between the equipment and systems for the electric power process, including telecontrol, teleprotection and all other telecommunications to control the electric power system. Its scope and titles were changed in 1994 and 2003 to take into account system aspects in addition to equipment aspects and changes in power systems management.

Power systems management comprises control within control centres, substations and individual pieces of primary equipment including telecontrol and interfaces to equipment, systems and databases, some of which may be outside the scope of TC 57.

Comprehensive remit

The role of IEC TC 57, as outlined in its scope, is "to prepare international standards for power systems control equipment and systems including Energy Management Systems (EMS), Supervisory Control and Data Acquisition (SCADA), distribution automation, teleprotection, and associated information exchange for real-time and non-real-time information, used in the planning, operation and maintenance of power systems."

The scope also stresses that the special conditions in a high voltage (HV) environment have to be taken into consideration.

It also notes that International Standards developed by other IEC TCs as well as other standards and recommendations prepared by organizations like the International Organization for Standardization (ISO) and the International Telecommunication Union (ITU) "shall be used where applicable, as far as these standards or specifications fit consistently to TC 57 communication architecture."

Extensive structure and participation

To cover its very broad remit TC 57, which brings together 31 participating and 15 observer countries, set up the following 12 Working Groups (WGs):

  • WG 03: Telecontrol protocols
  • WG 09: Distribution automation using distribution line carrier systems
  • WG 10: Power system Intelligent Electronic Device (IED) communication and associated data models
  • WG 13: Energy management system application program interface (EMS - API)
  • WG 14: System interfaces for distribution management (SIDM)
  • WG 15: Data and communication security
  • WG 16: Deregulated energy market communications
  • WG 17: Communications systems for distributed energy resources (DER)
  • WG 18: Hydroelectric power plants – Communication for monitoring and control
  • WG 19: Interoperability within TC 57 on long term
  • WG 20: Planning of (single-sideband) power line carrier systems
  • WG 21: Interfaces and protocol profiles relevant to systems connected to the electrical grid

Work by three of these WGs: WG 10, WG 17 and WG 20, is of particular relevance to Smart Grid applications.

TC 57 also set up AHG 8: IPv6, an ad hoc Group created to look at the use of Internet Protocol version 6 (IPv6) as a network protocol for IEC TC 57 standards.

In addition to these, TC 57 formed two Joint WGs (JWGs): JWG 16, with (and managed by) IEC TC 13: Electrical energy measurement and control, on common information model and data models and message profiles for automatic electricity metering data exchange; and JWG 25, with (and managed by) IEC TC 88: Wind turbines, for communications for monitoring and control of wind power plants.

A very large number of experts, close to 620, are active in TC 57, reflecting the importance and interest the electric power industry attaches to its work.

As of September 2015, TC 57 had issued more than 140 publications, and had nearly 60 projects in development.

Trends driving standardization work

Both technology and market trends drive TC 57 standardization work.

Constant and fast developments in information and communication technology (ICT) have a direct impact on the work of TC 57, which needs to follow these developments to seize and integrate solutions to achieve a rapid implementation of Standards.

Interoperability is essential for automated power systems, this applies to communication between utilities and users and requires the adoption of similar technologies on both side, at least in terms of communication systems (protocols, data).

Two-way traffic involving other IEC TCs

TC 57 work requires establishing liaisons with a number of other IEC TCs. It is a supplier of Standards to TCs that develop International Standards for measuring equipment, including meters, for HV switchgear and controlgear assemblies, for instrument transformers and for renewable energy sources (hydropower and wind turbines).

TC 57 is also a customer of Standards developed by IEC TC 8: Systems aspects for electrical energy supply, and IEC TC 65: Industrial-process measurement, control and automation.

In addition TC 57 maintains liaisons with other IEC TCs that have degree of connection with Smart Grid issues, like IEC TC 69: Electric road vehicles and electric industrial trucks, Project Committee (PC) 118:  Smart grid user interface, IEC TC 120: Electrical Energy Storage (EES) Systems.

As new types of grids that rely increasingly on the exchange of information are being introduced in many countries, International Standards developed by IEC TC 57 will play a critical role in the rollout of future power supply and distribution infrastructures.

Overhead power lines TC 57 develops Standards for the transmission of data through power lines
wind turbines TC 57 Standards will be central to the integration of renewables into grids
Substation Substations rely on TC 57 Standards for the interoperability of their systems