Thread: 400MW Generator pulling too many MVARS (lagging power factor)

Please read the OP again. Quote " when we tie on the MVARS are running ~60-80 MVARS at almost no load (5-10 MW). Usually we run 0-10 MVARS at 0-10 MW. The power factor is .1-.3" The voltage setpoint at synchronizing is set by the synchronizer.  It is unlikely that the voltages match just at synchronizing and then just after synchronizing the system voltage changes, or even if the AVR setpoint changes. It is more...

Mode is voltage control. 22kv generator terminal. 230kv high side. Metering Pt's are good as are meters. You think they are raising field current too high. Field (rotor) and stator are newly re-wound.

What operating mode?  Voltage control?  Watt/VAr control?  Power factor control?

( Utility machines are usually despatched separately on load and reactive load: PF control ties them together, so a change in MW also requires adjustment to the AVR. One more job than there needs to be!    , )

( Quote: Synchronizing with big differences in voltage magnitude a large MVAR power flow will appear across the CB as it is closed. We know.     , )

( Clarification in bold: Quote: ...One other thing, the vars at a given voltage depends not only on generator and it's control, but on the grid operating conditions .... which may have changed.   , )

( Good point Pete. If the grid voltage drops and the AVR does not make a correction, expect a lot of VARs. , )

Invert the polarity of the droop CT and see how is the behaviour

If this is a parallelling generator then why not operate in PF mode? In AVR mode if voltage setting is higher than utility voltage excitation will increase trying to raise terminal voltage into an infinite load, increasing vars output. Generator output power (KW) is controlled by energy source (turbine, diesel, etc.) only, not load.  

( Synchronizing with big differences in voltage magnitude a large MVAR power flow will appear across the CB as it is closed. , )