Versant to install synchronous condenser at Maine substation
Versant crews will be installing a synchronous condenser at the Boggy Brook substation in Ellsworth, Maine — marking the first time one has been installed on Versant’s transmission system.
The 12-foot-tall, 100-ton device synchronous condenser provides short circuit current as well as voltage stability to the system. The synchronous motor rotates at set revolutions per minute, and the mass of the rotor adds inertia, resisting overvoltage in the case of excess generation, or providing voltage stabilization during times when generation is lower.
“If you think of power going to the transmission system like water flowing through a pipe, and then a hole appears in the pipe causing a leak, you can think of short circuit current as the backup water tank,” Versant Project Manager Brian Green said. “The synchronous condenser is generating that current and keeping power supply flowing on the transmission system.”
The need for this device was identified in a 2021 ISO-New England study, which found situations that could potentially cause voltage irregularity within the Down East loop electrical system. To regulate voltage in certain scenarios, such as the addition of wind generation, the study found that the Down East Loop system could benefit from an increase in short circuit current. Short circuit current stabilizes power supply for renewable energy sources, provides the necessary power to ensure reliable service, detects faults, and helps maintain voltage levels in the event of service interruptions.
The Boggy Creek substation project also includes new power inductors that are electrically connected on a ring of breakers with the synchronous condenser. The inductors will help manage the reactive power on the transmission system and help to ensure reliable service.
Preliminary work at the site is underway. The condenser arrives from Brazil by boat this November and the project is expected to be completed in mid-2024.
