by Alex Apostolov, Editor-in-Chief

The Future is Now

One of the definitions of Future that we can find is "time regarded as still to come."


The Future is Now

If we ask many people about their opinion regarding digital substations and what they are doing about it, we are going to get many different answers. The differences depend on multiple factors, such as:

  • What do they understand a digital substation to be?
  • How comfortable they are with trying something new?
  • How well do they understand the benefits of digital substations in comparison with the conventional substations?


It is clear that we first need to clearly define what we mean by a digital substation. In my mind, I divide substations in three main categories:

  • Conventional substations are most of the substations around the world that are using only hardwired interfaces between the primary and secondary devices in the substation. All protection and control functions are performed by electromechanical or solid state devices that do not have communication capabilities
  • Hybrid substations are the growing number of substations all over the world that are using microprocessor based protection and control devices with some communication capabilities that can be used for data acquisition, event reporting, disturbance recording and many others. A more advanced version of hybrid substations are the ones that are using IEC 61850 as the communications protocol and especially GOOSE messages to replace the hardwired signals between the protection and control IEDs
  • Digital substations are the ones where all interfaces between the sensors, IEDs and other devices performing protection, automation, control, measurements, monitoring, recording, etc. are based on digital communications, predominantly using IEC 61850. The only hardwired interfaces are the power supply and the interfaces with the primary equipment ? for example circuit breakers and switches, power and instrument transformers. A more advanced version of digital substations are the ones with non-conventional instrument transformers

If we go back to the question about digital substations and what people are doing about them, the answer in many cases will be that they are being considered in the future, in a moment in time that is still to come.
The good news is that not everybody feels that way.
That is why we dedicated this issue of the PAC World magazine to digital substations - in order to show to the protection, automation and control specialists around the world that we have leaders in our industry that:

  • Have seen the benefits of the digital technology
  • Have done their homework and tested the technology to become comfortable with the conclusion that this is the way to go and that it is not something to do in the future, but what should be done now. And nobody can do it for us.

We need to see the digital substations, we have to build the concept and thoroughly test it to gain the confidence and make it happen.

Not in a moment in time that is still to come, but now.

"It is not in the stars to hold our destiny but in ourselves."
William Shakespeare