Generator Service Capabilities
With over 150 years of experience, Siemens-Energy is a world leader in generator technology and has manufactured many of the largest and most efficient generators in the world.
With Siemens-Energy as your service partner, you can have the full benefits of the expertise of our turbine-generator factory personnel, design engineering, service engineering groups, and our regional management and service expertise. We are knowledgeable of potential turbine-generator issues through significant fleet experience and have developed an enormous backlog of field processes, procedures, tooling and trained personnel to quickly address them.
Our Generator Service Capabilities in Detail
- AC Maintenance and Overpotential Tests
- DC Maintenance and Overpotential Tests
- Dielectric Absorption
- Leakage Voltage
- Insulation Resistance of Each Phase
- RTD and T/C Insulation Resistance
- Through Bolt Insulation Resistance
- Thermocouple Continuity
- Tube-to-Tube Resistance (If present)
- Tube-to-Copper Resistance (If present)
- RTD Internal Resistance Measurements
- Phase Resistance Measurements
- Transposition Test (If applicable)
- Stator Core SMCAS Test
RTD Element Resistance Test
Thermocouple Continuity
RTD or T/C Insulation Resistance
Diode Wheel:
- Fuse Testing
- Diode Forward/Reverse Resistance
- Capacitor Fuse Check (Mark III only)
- Diode Wheel to Heat Sink Insulation Resistance
- Diode Wheel to Exciter Shaft Insulation Resistance
- Diode Wheel-to-Diode Wheel Insulation Resistance
Exciter Rotor:
- Winding Resistance
- Winding Ring Insulation Resistance
- Ground Detection Ring Insulation Resistance
- Continuity of Ground Detection Ring to Armature
- Rotor Ground Protection Insulation Resistance
- Slip Ring to Ground Insulation Resistance
- A Ring to B Ring Insulation Resistance
Exciter Stator Assembly:
- AC Impedance & Pole Balance Test
- Winding Copper Resistance
- Winding Insulation Resistance
- Field Current Limiting Resistor Resistance
PMG Assembly:
- Winding Copper Resistance
- Winding Insulation Resistance
- Evacuating water from the generator windings is necessary for performing some electrical tests on the stator windings system
- Extremely useful in Leak Detection and Investigations
- Vacuum decay can be affected by moisture in system
- Helium leak detection can be affected
- Stator winding leak repairs
- Aids in Long term storage of or layup of the stator water cooling system
Loop Testing is performed to identify and restore insulation between core laminations, (if interlaminar insulation has broken down).
- Standard Loop testing is performed at an input frequency of 60 Hz and a voltage of 4,160 VAC (This tests the generator at rated flux density).
- Once energized, the stator core is scanned with a Thermographic camera for evidence of hot spots.
High Frequency Flux Test
- Magnetization of the stator core
- Production of magnetic / core losses to detect hot spots in fault locations by eddy currents at 480 VAC inputs, rather than at 4,160 VAC.
- Lower input Voltages and Currents allow for smaller cable sizes and customer demands.
- The VFPS, (Variable Frequency Power Supplies) can be run as stand alone units, or run in parallel for larger generators if needed.
- Thermovision scans are then performed similar to the 60 Hz loop tests but at variable frequencies, (usually around 500 Hz), to locate hot spots in the stator core iron.
Modal analysis determines the natural
frequencies and mode shapes of turbine-
generator static structures across the
relevant frequency ranges of operation.
Testing ensures that during operation the
structure is tuned away from resonant
conditions that increases structure fatigue
and chance of failure. Modal analysis can
be performed in the field or the factory.
Modal analysis applications include:
- Generator end windings
- Generator pedestals
- Generator frame
- Generator lead box
- Operational deflection shape (ODS)
- Blade frequency testing
- Turbine structural shaker test
- Rotor modal analysis
- Baffle plates
Further comprehensive Siemens Generator Service Capabilities can be offered upon request.