Question

Function of interpole flux is_________

(a) Neutralise the commutating self-induced emf

(b) Neutralise the armature reaction flux

(c) Neutralise both the armature reaction flux as well as commutating emf induced in the coil

(d) Perform none of the above functions

I have been asked this question in unit test.

My query is from Ways to Reduce Effects of Armature Reaction topic in section Armature Reaction of DC Machines

Answer 1

Correct option is (c) Neutralise both the armature reaction flux as well as commutating emf induced in the coil

The explanation is: Interpoles are designed to overcome the effects of the armature reactance and the self-induction of the machine i.e. to neutralise both the armature reaction flux as well as commutating emf induced in the coil.