Customized measurement systems that create great value

With tailored solutions for power quality measurement, Sundsvall Elnät has access to better information about what is happening in the grid. Taking readings has become much simpler and more reliable.

“We contacted Metrum because we wanted to begin measuring quality, both to ensure our delivery precision and to comply with future regulations and changes,” says Daniel Ytterström, operations engineer at Sundsvall Elnät. “Collaboration began back in 2005 and this was also when the first measurement instruments were installed in strategically important substations.”

Metrum PQ140 is now installed in all receiving and distributing substations, and in a delivery currently underway, the grid substations are being equipped with Metrum SC. The instrument has been installed in more than 500 substations to date. Metrum has also tailored the software, enabling that measurement data can be exported directly to the Tekla Xpower information system. After customization, the existing collection system MActor can also be used for radio communications with the substations.

Sundsvall Elnät has a stable grid and the system seldom identifies any larger problems; it is mostly a matter of registering deviations. Metrum’s system provides information about what is taking place in the grid, what can be considered as “normal”. A basic level has been established and when the grid is expanded, such as with connection to small-scale production, changes are easy to follow.

“With Metrum’s system we always know the status at all locations, all the time,” says Daniel Ytterström. “We know that we have a solid base for our operations as well as a detailed history at our disposal.”

Effective and exact

Data collection at Sundsvall Elnät is now easier and more reliable. Personnel previously drove out to the stations and to read off analog instruments that only provided relatively rough estimates. Readings are now made remotely, at the same time as the values registered are more exact and the sources of errors have become fewer.

Daniel Ytterström points out that the task – or rather the system – will never be finished. It is being constantly refined in keeping with the principle of continuous improvements. Even if many of the functionalities have been around from the start, loss and power analyses for example, have become significantly better, which provides a good basis for future planning.

According to Daniel Ytterström, Metrum was chosen as the supplier because they could deliver measurement instruments that were adapted to Sundsvall Elnät’s needs. The price was right and the equipment could also be quickly delivered.

“Metrum has been very accommodating and their customized solutions integrate exceedingly well in our open platform,” says Daniel. “When needed, we’ve also received excellent help from their support. We speak directly with their engineers without any unnecessary intermediaries.”

Long-term investment pays off

Even if the initiative for better measurement methods entails an initial investment, it pays for itself in the long run. As a bonus, there are many other advantages with the system; as long as all values stay within the established parameters, there is no need for time-consuming random tests and checks.

“As long as everything is ‘green’ we know that all is well and working just as it should,” says Daniel. “We don’t need to make checks because the system monitors itself.”

With Metrum’s equipment installed, Sundsval Elnät has also taken an important step in preparing for smart grids, the smart electrical grids of the future. Here it is a matter of handling both inflows and outflows in the grid, for large and small stakeholders.

“We are constantly striving to build up a flexible, future-oriented and expandable system with an open and simple platform,” says Daniel Ytterström in closing. “We have the instruments in place for when smart grids are introduced on a wider scale.”

Results of the collaboration
  • Control of energy flows and disturbances in power grid, clarifying financial responsibility
  • Improved decision making information with statistics and real-time readings
  • Improved information about power quality in accordance with applicable regulations
  • More efficient surveying of quality deviations
  • Shortened power outages

Sundsvall Elnät AB is a subsidiary of the municipal owned Sundsvall Energi AB. The company builds and administers the power grid for 27,000 private customers and more than 700 business and industrial customers in Sundsvall and the surrounding area. Energy delivery totals 737 GWh.

Read more about Sundsvall Elnät