generator running parallel

Discussion in 'Homework Help' started by eagle55, Mar 25, 2010.

  1. eagle55

    Thread Starter New Member

    Mar 9, 2010
    Two generator of same MVA rating running parallel, which one will deliver more/less/same load and why?

    If one those is higher rating, then what would be scenario?
  2. t_n_k

    AAC Fanatic!

    Mar 6, 2009
    This looks like homework. Perhaps you should post your question on the appropriate forum.
  3. R!f@@

    AAC Fanatic!

    Apr 2, 2009
    The generators will see the same load, and this is taken care of by the synchronizing panel.
  4. t_n_k

    AAC Fanatic!

    Mar 6, 2009
    It's possible for instance, that the individual machine excitation settings are intentionally made different - then one might expect a different load share. I'm not sure why one would do this - there may be a reason or reasons - say for the purposes of system stability or operational efficiency ...?
  5. JoeJester

    AAC Fanatic!

    Apr 26, 2005
    The reason you change excitations on two MG sets is to smoothly transfer the load from one to another. Raise the excitation on the MG taking the load and lower the MG going offline, after the synchronizers show the frequency is close to one another. Thirty-two years ago, the synchronizing lamps would flash very slowly during MG changes.

    Other than that, you try to keep them close enough to share the load.
  6. rdj

    New Member

    Mar 25, 2010
    Governor Speed Droop (GD)setting, this is the one responsible for your load sharing characteristic.

    GD = (f @ no load -f @ full load) / P @ full load

    Assuming "Speed/Load" control will not be adjusted.

    If two generator running in parallel have the same "GD" and (f @ no load), the load will be divided evenlly even the Power ratings are not the same.

    Try to make a graph (Frequency versus Power) with the following data.

    f1 & f2 @ no load = 61 Hz
    f1 @ full load = 60.5 Hz
    f2 @ full load = 60 Hz
    P1 @ full load = 2 MW
    P2 @ full load = 4 MW

    Now try to change any of the data and your GD will also change, hence load will not be divide evenlly.