In an alternator, for which type of load will the armature reaction be distortional?

Option 3 : Unity power factor

Armature Reaction: At on-load condition, the alternator has two fluxes interacting with each other. These are:-

1. Main flux due to rotor poles
2. Armature reaction flux: it is due to the load current flowing in the armature winding.
3. The interaction of the above two fluxes results in the resultant flux.

• ​At Zero power factor leading, the main flux and armature flux will be in the same direction. This will produce magnetizing armature reaction.

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• At Zero power factor lagging, the main flux and armature flux are in opposite directions. This will produce demagnetizing armature reaction.

  [ alt="F1 Savita Engineering 1-6-22 D21" src="//storage.googleapis.com/tb-img/production/22/06/F1_Savita_Engineering_1-6-22_D21.png" style="width: 307px; height: 191px;">            [ alt="F1 Savita Engineering 1-6-22 D22" src="//storage.googleapis.com/tb-img/production/22/06/F1_Savita_Engineering_1-6-22_D22.png" style="width: 236px; height: 215px;">

• At Unity Power factor, the main flux is in quadrature with armature flux. This will produce a cross-magnetizing armature reaction.

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