cosphi problem
cosphi problem
(OP)
While turbine is running, cosphi is decreasing from 0,95 to 0.35-0.40. Current is increasing from 30 A to 60 A. Voltage is decreasing from 10.800 to 10.000 V. Alternator is 50 Hz.Also, alternator NDE and DE side vibrations are quiet high that is about 6 mm/s on both sides and turbine gives alarm. Vibrations are measured with external device and it shows 6 mm/s too. What might be problem? this happenned suddenly.





RE: cosphi problem
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If we learn from our mistakes I'm getting a great education!
RE: cosphi problem
RE: cosphi problem
rmw
RE: cosphi problem
RE: cosphi problem
rmw
RE: cosphi problem
RE: cosphi problem
RE: cosphi problem
Does the AVR have different modes, such as voltage control, power factor control, constant reactive power, etc? What mode is selected? Do you understand how each mode will interact with a larger system?
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If we learn from our mistakes I'm getting a great education!
RE: cosphi problem
Electrical faults can be read by vibration systems as high vibrations (induced noise)
If the vibrations measured by the hand held equipment (like IRD or Bently Nevada):
1. matches the control system: there might be a problem in the generator field (rotor).
2. are different (and very low): there might be an electrical problem in the exciter.
Hope this helps, tell us how you fared.
saludos.
a.