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The generator whose field magnet winding is supplied from an independent external DC source is called:

The generator whose field magnet winding is supplied from an independent external DC source is called: Correct Answer separately excited DC generator

Classification of DC Machine:

The DC machine can be classified as,

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1. Separately Excited DC Machine:
A DC Machine whose field magnet winding is supplied from an independent external DC source (e.g., a battery, etc.) is called a separate DC Machine.

2. Self-Excited DC Machine: A DC Machine whose field magnet winding is supplied current from the output or input of the DC Machine itself is called a self-excited DC Machine.

There are three types of self-excited DC Machine depending upon the manner in which the field winding is connected to the armature, namely;

(i) Series DC Machine
(ii) Shunt DC Machine
(iii) Compound DC Machine

(i) Series DC Machine: In a series-wound DC Machine, the field winding is connected in series with armature winding so that the whole armature current flows through the field winding as well as the load.

(ii) Shunt DC Machine:

  • In a shunt DC Machine, the field winding is connected in parallel with the armature winding so that the terminal voltage of the generator is applied across it.
  • The shunt field winding has many turns of fine wire having high resistance.
  • Therefore, only a part of the armature current or supply flows through shunt field winding and the rest flows through the load or armature.
     

(iii) Compound DC Machine:

  • In a compound-wound DC Machine, there are two sets of field windings on each pole, one is in series and the other in parallel with the armature.
  • A compound wound DC Machine may be:
  1. Short Shunt in which only shunt field winding is in parallel with the armature winding.
  2. Long Shunt in which shunt field winding is in parallel with both series field and armature winding.

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