By Fred TuckerDecember 9, 2013
KUTTAWA, Ky., (Dec. 6, 2013) -- The U.S. Army Corps of Engineers Nashville District's Barkley Hydropower Plant Unit 1 here is back in operation after a phase-to-ground fault caused a fire that damaged the 32.5 Megawatt generator stator windings in Dec. 19, 2010.
"This $11.5 million, major repair project began Aug. 15, 2012 when contractor employees lifted the 270-ton assembly by crane and placed it on a nearby pedestal for repair by National Electric Coil from Columbus, Ohio," said Jamie James, Nashville District project manager.
After a complete inspection of the disassembled unit it was determined that a complete generator stator rewind would be required to repair the 47-year-old unit initially placed on line in 1966, according to James.
"Twenty-three field poles were removed from the rotor, shipped to NEC's Columbus, Ohio facility for refurbishing, returned and reinstalled in the Barkley unit," James said. "NEC also manufactured and installed core laminations and stator coils," he added.
Teamwork and exceptional communication among the Nashville District team and with the contractor were required to schedule and complete the various work included in the project according to James.
Asbestos and lead paint abatement, bearing refurbishment, thermal sensor, air cooler replacement, bus rings, field verification measurements for fit and alignment, testing of the components and unit, and reassembly were choreographed to successfully complete the project.
"Tracking all the work, responding to new information, and moving the project forward required exceptional communication among the LRN team and with the contractor and I commend all involved. The Resident Engineer's office and hydropower plant personnel worked very well in integrating the construction and daily plant operations," James said.
The repaired Unit 1 generator is functioning as designed and there have been no issues with it since it was placed back in service Nov. 18, 2013 according to Jamie Holt, Barkley power plant specialist.
"We did a 72-hour run test on Unit 1 prior to placing it back on line Nov. 18, and we will conduct a special test in Spring 2014 after a break-in period to check stator irons, coils, alignments, proper lubrication and for anything out of the ordinary prior to fiscal completion of the project," Holt said.
Word spread quickly among local right bank fishermen and commercial fishermen seeking baitfish that Unit 1 generator was back in operation according to Holt.
"Fishing activity of bank fishermen has returned to about normal, now that Unit 1 is generating again," Holt said, adding that, "They can cast from the right bank into the turbine's turbulent discharge without risking a waterborne accident in this dangerous area."