Automated ‘smart’ switches enhance service restorations

When the power goes off, customers – and Oncor – are counting the minutes until it comes back on. It’s why Oncor is now deploying an automated technology in some areas that helps reduce the time it takes to restore service after an electrical fault.

The technology is an automated and connected switch called the IntelliRupter. Oncor is installing teams of IntelliRupters on mainline Distribution circuits across our service territory.

“They truly are automated,” said Derek Bohne, Manager of Distribution Programs. “IntelliRupter switches operate in teams to restore service without the need for a system operation to take action.”

“They’re constantly checking with each other for power abnormalities,” Bohne said. “If any two switches in a team detect a fault, they signal one another and work together to automatically restore power to unfaulted segments of our system.”

A fault is any abnormal electric current. Faults are commonly caused by a live animal, like a squirrel, a car hitting a pole, strong winds, or falling trees on electrical wire. The result can be an outage that knocks out the power in that area.

Bohne said the IntelliRupter can quickly restore service to the unfaulted portion of the lines, rather than having an entire area without service.

“IntelliRupter technology helps us reduce average outage times from 45 minutes to as little as two minutes on unfaulted feeder segments,” he said.

The reduction in the average restoration time is the result of not having the DOCs intervene or dispatch a line worker to find the fault and manually isolate it. Oncor must still dispatch a Distribution crew to repair any damage on faulted segments.

Oncor began full-scale deployment of IntelliRupter switches in 2017. The company has committed over $700 million through 2026 to more widely implement the technology, along with other Distribution technologies. Oncor has the second-largest deployment of IntelliRupter switches in the U.S.

“We’re deploying automation equipment across the entire system,” Bohne said. “The goal is to have this technology benefit as many customers as possible by the end of our deployment plan in 2026.”

Oncor installs the IntelliRupter switches in areas where there are two feeders, or sources of electricity, so the load can be switched back and forth, Bohne said.

The IntelliRupter technology also helps Oncor preserve the life of its system assets because the switches use 95 percent less power to detect a fault than a traditional reclosing device.

Bohne said IntelliRupter is one of five automated technologies now being deployed by Oncor. Nearly 45 percent of Oncor’s customers are now benefiting from the deployment of automation equipment, with more to come, he said.

IntelliRupters are expected to have a large impact in reducing the duration of outages and on the System Average Interruption Duration Index (SAIDI).

“A big factor in our leadership team’s commitment to IntelliRupter installation is the positive affect it has on SAIDI,” Bohne said. “It directly ties to our annual and long term goals for reliability and these switches play a key role in getting us there.”

So now, customers – and Oncor – don’t have to watch the clock quite as long.