EXPERIENCE WITH ON-LINE CONTINUOUS MONITORING OF TURBINE GENERATOR STATOR AND ROTOR WINDINGS

Rotor flux monitoring and on-line partial discharge monitoring are well known tools that help plant owners to detect many developing rotor and stator winding problems in air and hydrogen cooled turbine generators. Both monitors are widely used by the utility industry. Most users periodically monitor the flux and PD using portable instrumentation that is connected to permanently installed sensors for a short period of time, usually once or twice per year. However, since 1994, continuous PD monitoring was commercially introduced, and shortly after, continuous flux monitoring started to be deployed. This paper will describe the continuous winding monitoring systems that are currently in use, and outlines the advantages and limitation of such systems. Case studies of the use of such continuous monitors will also be presented.