Preventative maintenance of turbine-generator stator windings

The authors discuss stator winding deterioration mechanisms and their consequences. Inspection and test procedures which will detect these mechanisms, as well as programs to arrest them, are also discussed. The analysis is broken down into sections on the slot region of the stator winding and on the end winding region. Particular emphasis is directed to issues unique to liquid cooled stator windings. A simple test is described which can be used to detect the presence of excessive amounts of water in the insulation of a liquid cooled winding