Stator Winding Life Extension Possible With
Main-Neutral Interchange
Many modern air cooled generators are deteriorating to the point that a stator rewind is needed. Some of these units, such as the WESTAC, and even some of the newer Aeropac designs, have required stator rewinds in under 10 years of operational life. These stator windings, in many respects, have been subjected life-threatening stresses. They operate at higher than desired temperatures and are subject to high partial discharges in the slot.
NEC offers an intermediate solution that can significantly extend the life of a winding, the main-neutral interchange, also known as a "M-N conversion" in engineer's shorthand.