Generator Repair Capabilities
To keep outage windows at a minimum, our generator service group is turn-key and field based, providing stator and rotor inspections and most repairs at the plant site. Some common repairs include:
- Stator re-wedging
- Rotor retaining ring removal / replacement
- Stator core repairs
- End winding repairs
- Rotor and Stator Rewinds
Generator Testing Programs
GRIP 1,2, and 3 (Generator Reliability Inspection Program) Testing Programs
The GRIP inspections are built around outage durations for typical turbine inspections; thus the generator never becomes the critical path of the outage unless an outage is planned specifically to address major maintenance on the generator
GRIP 1: This rotor-in inspection program is designed to fit in a 1-2 day turbine outage window
- Visual and Borescope inspection of stator windings, rotor windings, associated blocking (as accessible), stator core step iron, and fingerplates
- Perform tests of Resistance Temperature Detectors (RTDs), stator windings, and rotor windings
- Stator Winding Tests: Insulation Resistance, Polarization Index and Copper Resistance
- Rotor Winding Tests: Insulation Resistance, Polarization Index, Copper Resistance and AC Impedance
- Exciter Inspection: Visual inspection and Insulation Resistance testing
Benefits
- Reveals pending faults in windings of the stator, rotor and exciter
- Reveals deterioration of stator winding insulation caused by partial discharge activity or end winding vibration
- Establishes a baseline for evaluating future inspections and input for establishing planned major maintenance activities
- Written and digital documentation of critical generator components for planning future maintenance
GRIP 3: This rotor-out inspection is designed to fit in a Major Inspection turbine outage window Inspections / Tests Performed
- GRIP-1 and GRIP- 2 tests and assessments, plus:
- Additional Stator Winding Examinations: El CID core test, and Wedge Tightness Mapping
- Additional Rotor Winding Examination: Retaining Ring NDE Inspection (based on OEM requirements)
Additional Benefits
- Reveals partial discharge activity and deterioration in windings, blocking and core tightness which were obstructed by a rotor-in examination
- Record of stator core lamination condition
- Record of rotor retaining ring, wedge and rotor body condition
- Essential documentation to establish a trend report to monitor future deterioration
Ready to speak to a PSG representative about this service? Please visit our contact page to send us a message or call (800) 226-7557 to begin the conversation.