Compensating windings are used in D.C. generators?

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1 Answer

Answer :

Compensating windings are used in D.C. generators to neutralise the cross-magnetising effect of the armature reaction.

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A 220 V D.C. generator is run at full speed without any excitation. The open circuit voltage will be?

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In a D.C. generator in case the resistance of the field winding is increased, then output voltage will?

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A D.C. generator can be considered as?

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To avoid formation of grooves in the commutator of a D.C. machine?

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In a D.C. generator the critical resistance refers to the resistance of?

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Flashing the field of D.C. generator means?

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In a D.C. generator the magnetic neutral axis coincides with the geometrical neutral axis, when?

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The e.m.f. generated in a D.C. generator is directly proportional to?

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In a D.C. generator the number of mechanical degrees and electrical degrees will be the same when?

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D.C. generator generally preferred for charging automobile batteries is?

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The armature core of a D.C. generator is usually made of?

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In a D.C. generator the ripples in the direct e.m.f. generated are reduced by?

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The demagnetising component of armature reaction in a D.C. generator?

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In case of D.C. machine winding, number of commutator segments is equal to?

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Eddy currents are induced in the pole shoes of a D.C. machine due to?

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Last Answer : Eddy currents are induced in the pole shoes of a D.C. machine due to relative rotation between field and armature.

If brushes of a D.C. generator are moved in order to bring these brushes in magnetic neutral axis, there will be?

Last Answer : If brushes of a D.C. generator are moved in order to bring these brushes in magnetic neutral axis, there will be crossmagnetisation as well as demagnetising.