Critical device invention
Fault recorder results from experiments conducted by Donnie Eslinger, Darrell Goodson
EnergyLines October 2019
One of the electric power industry’s most important goals is ensuring the integrity of the nation’s power grid. Digital fault recorders are one technology used to monitor operations at substations and power plants throughout North America. The devices continually monitor the flow of electricity in and out of the substations. When they detect abnormalities such as faults, they record and relay the information so it can be analyzed.
You may be surprised to learn that this critically important equipment is the direct result of experiments conducted by Hoosier Energy employees at the Merom Generating Station.
Meter Relay Working Foreman Donnie Eslinger was part of the team preparing Merom for operations in the early 1980s. The 43-year Hoosier Energy employee and his co-worker Darrell Goodson took advantage of some downtime to experiment with locating the source of faults. “In those days, you did that with equipment that used a galvanometer and a light beam reflected on photo paper,” Eslinger recalled. “It produced squiggly little waveforms on the paper, and we would measure them with a ruler. We knew how many volts and amps were present, so we could use the waveforms to estimate a fault’s location. It was a cumbersome process, but it gave us a picture of what happened.”
Thinking digital technology might make it easier and faster to perform the computations, Eslinger brought his personal computer to Merom. The pair put it to the test, developing an algorithm that simplified the computation process. Impressed with their idea, System Protection Engineer Dan Souhrada shared it with a colleague who ran a company called USI. The men worked together to refine the concept.
“We knew the size of the conductors, structures mounted on the line, the reactance, and the resistance, so we punched all of those figures into the program, and it was the basis for how we calculated a fault’s location,” said Eslinger. USI combined the concept with digital storage, and the digital fault recorder was born.
The technology instantly alerts system controllers to problems and pinpoints their location, so crews can be dispatched more quickly. “In the old days, we didn’t know exactly where the problem was, so we’d try to open a switch somewhere in the area and see if that was close,” Eslinger explained. “Now we have a GPS map that shows exactly where the problem is and what the nearest pole number is. That saves the member from being without power as long and it reduces the revenue we lose from the outage.” Fault recorders make it easier to troubleshoot other issues, too.
Eslinger modestly chuckled at being called an innovator, adding “I feel good that I worked on something that benefits the industry and is used all over the United States.”