Why do we give DC excitation to AC Synchronous motor??

Answer Posted / ghanshyam singh

because only dc current can produce the fixed pole i.e. the
poles produced by the dc current does not change with time
as in the case of the poles produced by ac current.
now when the stator of the machine is supplied the ac
current the rotating magnetic current is produced.
the dc excitation is necessary so that the poles produced
by the dc current and ac current both attrect each other
which will be responsible for the production of the torque.

Is This Answer Correct ?    46 Yes 6 No



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