An international standard known as IEC 61850 was created to enhance communication and interoperability among intelligent electronic devices or IEDs at substations. In contrast to signal-oriented protocols like Modbus, DNP3, or IEC 60870, which have different data structures, IEC 61850 is object-oriented; that is, it defines abstract data models using a common terminology. As a result, IEC 61850 GOOSE, MMS, and SMV protocols make it possible to map IEDs consistently and do away with the need for vendor-specific libraries to reveal the significance of every data point. Owing to the numerous benefits it offers going forward, the standard has solidified over time and is being used in areas other than power system automation, such as distributed energy resources (DER).
IEC 61850 Substation Architecture
Various intelligent electronic devices (IED) for switches, transformers, or measurement apparatus make up a switchgear. These gadgets need to be able to speak with one another. Each one has the ability to start urgent processes, like cutting off a load connection. These switchgear systems are categorised into three levels by the IEC 61850 standard series, which also outlines the communication protocol between the various switchgear system functions:
Process Level
Devices for acquiring data on current, voltage, and other parameters, such as circuit breakers, are found at the process level. The electrical energy is switched at this point.
Bay Level
The individual IEDs make up the Bay Level. They process the information provided by the process level and decide on local control. Additionally, they provide data to the SCADA system, a higher-level control and data collection system, for additional processing and monitoring.
Station Level
The SCADA system and the HMIs (handheld monitoring instruments) used to keep an eye on a substation’s operations are located at the station level. Additionally, from here, a variety of WAN technologies are used to link to the network operator’s network control system.
IEC 61850 in Substation Automation System
The substation, where a vast amount of data is shared among numerous Intelligent Electronic Devices (IEDs), was given the IEC 61850 standard concept. The core of the substation automation system is made up of these IEDs. IEC 61850, which has practical utility that was absent from earlier master slave standards like Distributed Network Protocol (DNP), IEC 60870, etc., currently governs substation communication. Peer-to-peer connectivity, data speed, eXtensible Markup Language (XML) syntax for configurations, and the availability of communication conformance testing are just a few advantages that the IEC 61850 builds upon from earlier standards. The performance and functional testing of IEDs are altered when IEC 61850 is used for the substation automation system.
Owing to IEC 61850’s rise to prominence as the primary protocol for substation automation systems (SAS), numerous studies have been published regarding the standard’s increased applicability and usage for substation functions. The changes needed to create, set up, and test an SAS with an IEC 61850 basis have been discussed. It has also covered the change from a substation physical architecture to a logical architecture based on IEC 61850. There are three levels of the SAS, which was based on IEC 61850. The first level of a substation’s functioning was its power system, followed by reliability in second place and visibility in third.
Advantages of Using IEC 61850 for Substation Automation
Power engineering projects can benefit greatly from using IEC 61850 for substation automation. These benefits include expanded functionality and flexibility, lower costs and complexity, better performance and reliability, and improved integration and interoperability. Using a standard data model and communication services, IEC 61850 facilitates the coordination and communication of various substation automation equipment from various suppliers and generations. By leveraging a single configuration language and network architecture, it makes the configuration and management of these devices easier. Additionally, by utilising network protocols and high-speed, high-availability communication services, it facilitates dependable, quick communication and management of substation automation equipment. Lastly, it makes it possible to use a comprehensive and flexible data model and communication services to construct sophisticated and customised functionalities for substation automation devices.
Impact of IEC 61850 on Substation Automation
IEC 61850 will not alter Substation Automation’s fundamental functioning, which is determined by its responsibilities. It appears that there hasn’t been much of a change to the system design either. However, as communication is the foundation of SA, IEC 61850 is the most crucial key for system design. Numerous built-in characteristics of IEC 61850, such as the use of object-oriented data models and the choice of widely used communication technologies, enable highly focused response to needs specified in client specifications that are not dependent on random variables but rather on defined guidelines. As a result, these characteristics aid in the creation of optimised systems. Functional performance is only one part of optimisation; other economic factors include investment, availability, expandability, and maintainability, or total life cycle costs.
Conclusion
In order to manage, control, and safeguard the infrastructure, substation automation is becoming more and more crucial as the grid’s complexity rises due to rising generation and demand as well as the greater penetration of intermittent renewable energy sources. Utilities have a great chance to enhance their operations using the latest advancements in communication standards and protocols for substation automation. The abstract model, independent protocol, standardised object names, self-describing devices, many high-level services, and SCL are just a few of the advantages that come with IEC 61850. These features remove procurement ambiguity, enable inter-device operability and the development of new capabilities, and reduce installation, commissioning, migration, integration, and extension costs. Because IEC 61850 enables applications to be expanded and changed without altering the communication stack, networks are future-proofed to suit the changing needs of utilities. Additionally, it makes it possible to integrate devices made by many manufacturers into the network architecture, fostering long-term network growth and flexibility.
