What is the difference between self-excited and separately excited DC generator?

What is the difference between self-excited and separately excited DC generator? 
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1 Answer

Answer :

Self-excited generator: In a self-excited generator the field winding is excited by an external DC source like a battery etc.

Separately excited generator: In a separately excited generator the field poles have some residual magnetism. When the armature is rotated a small emf is induced in it. This is fed to the field winding and if the current direction is such that it adds the residual magnetic flux to the field winding and the field strength is increased. The more emf in the armature, which is again fed to the field winding and goes on till the generator builds up voltage. 
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Enlist types of dc generator?

Description : Enlist types of dc generator?

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