Since the need to modernize the grid vastly overwhelms available resources, DSOs are challenged with selecting the best solutions for the most pressing problems to make the greatest overall impact. To create network automation products and smart solutions they need most, Ensto’s mission is to listen carefully.
Distribution system operators (DSOs) find themselves between a rock and a hard place. Their utility networks are confronted with challenges never before seen in history: in the face of global warming, there is pressure to reduce our carbon footprint and to increase grid resilience yet, at the same time, consumers are using more energy than ever before.
Each year, regulatory bodies impose stricter requirements on DSOs for quality of electricity, measured by the SAIDI and SAIFI indices, and each year DSOs must lower the duration and frequency of interruptions and reduce the number of customers impacted. Given limited resources, they must choose their battles carefully, implementing the right solutions, those which can deliver the greatest impact. Those unable to reach the SAIDI/SAIFI levels agreed with regulators risk high financial penalties and the dissatisfaction of end-users.
Network automation and smart technologies are available which can solve these problems for DSOs. But to modernize an entire network is cost prohibitive, and so DSOs must make sure their investments in technology, as well as their linemen in the field, are in the right places.
“Our ultimate role at Ensto is to help DSOs move from fault-driven maintenance to where they can predict the faults and optimize the costs and resources needed for daily operation,” says Roman Jaloza, Ensto’s R&D Manager of the Smart Technology Team.
“Personnel costs are growing and you can’t afford to have teams roaming around checking equipment conditions and looking for faults. DSOs can’t do all the maintenance themselves. Over the past 65 years Ensto has gained experience and expert knowledge to help DSOs reduce costs with smart solutions.”
In a “dumb” network, a tree falls on a line in a medium-voltage network, and the DSO's linemen must drive around the countryside looking for the fault. In this situation, the average outage duration is several hours.
But in a smart network, a tree falls on a line causing a fault, a sensor recognizes this, a load breaking switch and recloser isolate the faulty section and almost simultaneously send a report to the DSO’s SCADA where the FLISR (Fault Location, Isolation, and Service Restoration) system protects the wider part of the network. The area without electricity is reduced to a minimum, the network is reconfigured in tens of seconds, the linemen know where to go, and the duration of complete outage is significantly shortened.
“Think of network automation as a group of devices which bring the possibility to manage network behavior,” explains Ensto’s Pascal Pedrinelli, Director, Product Management, Network Automation. “In this group of devices, you’ll find sensors to collect measurements, RTUs, and central energy monitoring systems which analyze collected data and transmit it to SCADA so the DSO knows what’s wrong or what’s at risk and where.” Ultimately, he says, a smart network can self-adjust based on data, reconfigure itself, and even auto-repair. “Network automation and smart solutions are the natural solutions, of course, but they require long-term investments and integrations.”
"The historic precursor of some of Ensto's solutions is a simple air switch disconnector with no smart functions," says Pedrinelli. "From this we developed products with more capacity and all-weather capabilities." One product which came from this is Auguste, which ensures a network is open so repairs can be made with full safety. Produced by Ensto in Bagnères-de-Bigorre, France, Auguste is the only load-break switch on the market with the safe advantage of an embedded voltage transformer. Auguste can operate with 630 amps and is a very popular export product all over the world, especially in Europe and Africa.
The Ensto team in France also produces the Smartcloser, a circuit breaker that’s smart. It automatically determines where the fault is and tries to reinstall the network itself. “If a tree branch brushes the line or there’s a bird on the line, the recloser can reinstall the network alone,” says Pedrinelli. “It’s robust in capacity to break power – up to 12,500 amps, 20 times more than Auguste.”
Another advancement that Pedrinelli's team has made is in cybersecurity. "We have highly accurate sensors installed around the switch that collect data. At the bottom of poles we have control cabinets that manage data collected. These E-RTU cabinets observe the network and use amperometric and directional techniques to determine fault. We have a cybersecurity system in place for transferring the data to the SCADA system, making sure our clients aren't subject to a cyberattack. Our products today are protected and we follow the IEC 62351 standard.”
Farther north, Ensto in Finland also has a whole arsenal of products to make networks smart. On the safety side, Ensto Protrol, a Sweden-based company that Ensto acquired in 2021, produces fault detectors for over current and earth fault, with integrated remote terminal unit functionality.
"Protrol has a patented algorithm that is very accurate," says Harri Tuononen, Sales Manager, Network Automation, Ensto Finland. "It uses only phase current measurements by affordable split core current transformers to detect earth faults directionally and selectively. It has many other functions and features, such as automatic fault isolation and a transient fault recorder. It's the only fault indicator of its kind I've seen that works flawlessly. It's everything you need outside the primary substation."
Arcteq Relays, a part of Ensto Group, is a Finnish company that makes protection relay products for global markets. "For decades Finland has been at the top when it comes protection relay," says Tuononen. "I worked 10 years in primary substation and network automation commissioning and programming, and Arcteq is one of the simplest and easiest products to use. It is very accurate. Its arc protection is great."
The latest technologies used in Arcteq's relays give engineers a completely new range of solutions for any protection and control application, from utilities and power plants to wind power and heavy industry applications (offshore, marine), as well as industrial and institutional electrical systems.
Ensto in Finland also excels in the development of power quality, which make low-voltage grid power quality improvements. A Phase Balancer mitigates voltage unbalance in low-voltage distribution networks and improves safety at the same time. It’s an easy and cost-effective way to enjoy safe and balanced electricity without worrying about light flicker or overloaded networks. A communication interface enables remote device and power quality condition monitoring and improves low-voltage network observability.
Despite this impressive array of products, the main challenge is keeping things simple for the customer, says Roman Jaloza, Ensto's Smart Technology Team's R&D chief. "Many smart devices that are currently on the market are too complicated. A good smart product has to be easy to use for end users. Logic and analysis need to be used more locally, in places where issues are present. It’s got to support the users with as much useful data as possible without requiring them to be IT experts."
"One of Ensto’s goals is customer centricity. Ensto is on the customer’s side. We listen at the local level. We have connections with line workers. We get their opinions about our products, but we most want to hear about the challenges they face. Keep in mind it’s the line worker who installs and maintains the product. Overall, the added value of really smart products is seen across the DSO’s entire daily operations."
It is possible to imagine a sci-fi future for smart networks. Ensto has already begun to investigate possible applications for artificial intelligence and machine learning in its products. And Ensto also is interested in the cloud. "But everybody puts it in cloud and uses big computation power to make analysis," says Jaloza. "And this is useful in some applications. But that is only one side of the coin. To really be experts we need local analysis based on long-term experience. DSO customers expect a fast response. We make the analysis locally, bring intelligence to end devices and groups of devices, and then we have the fastest response."
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