Why DC excitation is used for alternators? Why cant it be AC?

Answer Posted / vknt

if we are using DC supply for field it will create the
rotating magnetic field as the rotor rotates. so there will
be a relative speed between field and stator coil to produce
voltage.

if we are using AC supply for field this will create
alternating field in rotor. as the rotor and field both are
rotating the net speed of the field will be zero i.e there
will not be a relative speed between filed and stator. so
voltage will not be produced in stator.

Is This Answer Correct ?    3 Yes 11 No



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