Running Gear: Two Leffel Francis turbines and synchronous generators
Scope: Replacement of control system
This project is part of a successful mixed-use redevelopment of an historic paper mill. Power is used both on site, and exported for sale, making the commercial facility a net-zero building. The plant has two vertical shaft Francis turbines, with directly connected synchronous generators. Until the upgrades by PHT, the original, fully manual controls from the 1930s, were still in place (with some more recent rework), as were the Woodward governors.
PHT was hired to provide new digital controls, Payne static exciters, and to retrofit the existing governor bases with all-new hydraulics. Due to legacy water use restrictions for operating on the historic canal system (restrictions dating back to use agreements made in the 1800s), this plant is only allowed to operate 16 hours per day, 6 days a week (corresponding to the two historic mill work shifts). Prior to automation by PHT, an operator would have to start the plant manually every morning at 6am, and then manually shut down the units every evening at 10pm. PHT automated this schedule, so that the plant automatically follows the schedule set by the operator, without the need to be on site.