IEC 61850 powering digital substations
IEC 61850 enables faster, safer, and interoperable communication in substation automation by standardising how intelligent devices exchange critical data.
Image for illustrative purposes
Substations are crucial nodes within the power grid, managing the flow of electricity between transmission and distribution lines. Depending on their role, substations either increase or decrease voltage levels using step-up or step-down transformers. Much like routers in a data network, substations receive, process, and redirect electricity to its intended destination. However, unlike routers, substations handle live power and must include fault detection, tolerance, and recovery features – especially those operating in remote or harsh environments.
This necessity led to the development of Substation Automation Systems (SAS), which incorporate microprocessor-based Intelligent Electronic Devices (IEDs). These devices handle key functions like protection, control, measurement, and communication. Initially, IEDs from different manufacturers used various proprietary protocols, complicating interoperability and requiring expensive protocol converters that also added latency.
To streamline communication and ensure seamless operation, the IEC 61850 standard was introduced. This internationally recognized protocol enables all IEDs within a substation to communicate over Ethernet, eliminating the need for converters and reducing network delays. It also simplifies configuration, testing, and project management across the entire automation system.
IEC 61850 enhances the performance of various IEDs in the system, including Merged Units (MU), Protection IEDs, Control IEDs, and Breaker IEDs. MUs convert analog current and voltage signals from transformers into digital data. These digitized values are sent to Protection IEDs, which continuously monitor for abnormalities. If a fault is detected, a trip message is issued, prompting the system to isolate the problem area. Simultaneously, Breaker IEDs send Generic Object-Oriented Substation Event (GOOSE) messages to update the network on the system status.
These messages – sample values, trip signals, and GOOSE alerts – are considered time-critical. Delays in processing or transmitting them could prevent fault isolation, risking system damage or outages.
In addition, Circuit Breaker Monitors (CBMs) verify whether breakers have operated correctly. If failures occur, both CBMs and Protection IEDs log these events and report them to the substation control system.
Through standardized, real-time communication and integrated monitoring, IEC 61850 has transformed how modern substations operate – enhancing safety, interoperability, and reliability across the power grid.
Source: EEP
#digital communication#fault detection#GOOSE#IEC 61850#IEDs#power grid control#protocol standard#Substation automation