Pattern Analysis of Turbine Generators On-Line Discharge Zone Location in Winding

Condition-based maintenance for turbine generators (TG) is given in the paper. Defects in stator winding and in magnet core are determined before repair on the basis of double-coordinate on-line discharge events location. Full information about ground wall semiconductivity layer in bars, slot discharges, sparking between plates in magnet core are provided by generators measurements operating load from W-min to W-max. Defect diagnostics have affirmed the forecasted failures: 1) migrating iron particles were detected through location and were registered protractedly by in-service installed continuum monitoring system for TG; 2) sparking in core located; 3) partial discharges (PD) located; 4) slot discharges located. The quality of the repair work has been monitored by the double-coordinate location and operating load variation, tests have confirmed defect absence.