Rewind Experience of Hydrogenerators within the Army Corps of Engineers, Portland District

摘要

Portland District has 3 large powerhouses (5043.2 MW) and 9 small powerhouses (457 MW). As our plants are aging, more and more of the generating units are showing problems which can no longer be fixed with repairs; the most economical action is to completely replace the stator winding. This is often combined with other remedial work, such as replacing the bearings and repairing pits and erosion of the turbines. Over the past decade, we have performed rewinds as follows: (number of generators rewound, by year) In the past, rewinds were done on an as-needed basis, after a catastrophic failure. At the present time, more and more of our rewinds are being done on units that are still functional, but whose reliability is very much in question and whose projected remaining life is deemed to be very short.