Premium Membership ♕

Save 50% on all EEP Academy courses with Enterprise Membership Plan and study specialized LV/MV/HV technical articles & guides.

Home / Technical Articles / What will happen to digital substations once the internet drops dead? Massive blackouts?

The goods & bads of digital substations

Here at EEP, we have already covered multiple aspects of digital substations, ranging from design, upgradations, and whatnot. We may continue writing till eternity and still be left playing catchups with the latest addition to advancements in power systems design and operation. Nevertheless, in this article, our focus shall be on the possible contingencies and turn of events when the coveted connectivity of modern digital substations goes haywire.

What will happen to digital substations once the internet drops dead? Massive blackouts?
What will happen to digital substations once the internet drops dead? Massive blackouts?

Or, how to cope if the internet or ethernet is down in digital substations? Normally, a fully automated digital substation in a power grid is connected to a remote server through the internet over an optical channel.

Remote communication or the internet we know of today is associated with many functionalities in a digital substation, and its disruption is never a desirable situation for substation engineers.

Table of Contents:

  1. Demarcation of digital substations
  2. Emergence of ethernet and internet in digital substations
  3. What if no ethernet?
  4. Internet in digital substations
    1. Remote supervision and control
    2. Teleprotection
    3. Remote maintenance
  5. Conclusion and frequent queries
    1. Do digital substations fail to operate when the internet is down?
    2. Are digital substations ready for offline or analog operation?
    3. What could engineers do in that situation to maintain the power supply?
    4. Bracing against the internet failure: “Redundancy, contingency plans, and skilled technicians.”

1. Demarcation of digital substations

Substation automation, time synchronization, data acquisition, monitoring, and alarming are some of the primary functions either facilitated or enhanced by digital substations, having already existed in different forms and phases. The availability of a modern communication backbone has been instrumental in transforming the way substations are designed and operated.

That is what demarks the operational territory of a digital substation – IEC 68150 compliant communication and interoperability between the process and station level equipment, all channeled through ethernet or optical link.

The primary substation appliances like circuit breakers, power transformers, lightning arrestors, switches, etc. have remained almost the same over the years, irrespective of the communication modes adopted. So, it is fair to say that the concept of digital substations marks its territory starting from the selection of protective equipment (conventional versus IEDs – Intelligent Electronic Devices) and their mode of communication with sensors/ actuators and control centers.

Breach or abnormalities in this territory could trigger a catastrophe in substations.

Figure 1 – A concept diagram of a digital substation

A concept diagram of a digital substation
Figure 1 – A concept diagram of a digital substation

Go back to the Contents Table ↑

2. Emergence of ethernet and internet in digital substations

The introduction of microprocessor-based relays in the early 1970s in substations laid the foundation for the current sophisticated version of Substation Automation Systems, aided by first-generation digital serial communication options- RS 232 and RS 485.

Although very capable, they had their limitation in data transfer rate and coverage, which eventually pushed for the inception of ethernet, a more advanced serial data communication standard.

Initial forms of serial communications and respective ports primarily facilitated debugging of equipment and data acquisition. For instance, RS 232 was a suitable option for relaying information to SCADA systems and not for automation systems due to their point-to-point connectivity, low data transfer rate, and transmission coverage.

RS 485 was a clear upgrade over RS 232 due to its fast data transmission rate and differential mode of operation that allows multidrop connections suitable for automation systems.

Still, the substation automation systems were never at full potential until the introduction of ethernet as the ultimate serial communication option for digital substations. Their fast data transfer rate, connection flexibility via cable or fiber, and support for redundant connection topologies made them stand out from the rest.

As the substations now depend on ethernet connectivity more than ever, IEC 61850, an international standard defining communication protocols for intelligent devices at electrical substations, has readily succeeded the MODBUS, DNP3, and IEC 60870-5-103 communication protocols.

Premium Membership Required

This technical article/guide requires a Premium Membership. You can choose an annually based Plus, Pro, or Enterprise membership plan. Subscribe and enjoy studying specialized technical articles, online video courses, electrical engineering guides, and papers. With EEP’s premium membership, you get additional essence that enhances your knowledge and experience in low- medium- and high-voltage engineering fields.

Check out each plan’s benefits and choose the membership plan that works best for you or your organization.

Good To Know!Save 50% on all video courses by purchasing Enterprise plan.

Log In »Purchase »

Premium Membership

Get access to premium HV/MV/LV technical articles, electrical engineering guides, research studies and much more! It helps you to shape up your technical skills in your everyday life as an electrical engineer.
More Information

Bishal Lamichhane

Electrical Engineer (B.E Electrical, M. Sc Engineering) with specialization in energy systems planning. Actively involved in design and supervision of LV/MV substations, power supply augmentations and electrification for utilities and bulk consumers like airports and commercial entities. An enthusiast and scholar of power systems analysis.

Leave a Comment

Tell us what you're thinking. We care about your opinion! Please keep in mind that comments are moderated and rel="nofollow" is in use. So, please do not use a spammy keyword or a domain as your name, or it will be deleted. Let's have a professional and meaningful conversation instead. Thanks for dropping by!

four  +  five  =  

Learn How to Design Power Systems

Learn to design LV/MV/HV power systems through professional video courses. Lifetime access. Enjoy learning!

Subscribe to Weekly Newsletter

Subscribe to our Weekly Digest newsletter and receive free updates on new technical articles, video courses and guides (PDF).
EEP Academy Courses - A hand crafted cutting-edge electrical engineering knowledge