The introduction of interpoles in between the main pole improves the performance of
d.c. machines, because
(A) The interpole produces additional flux to augment the developed torque.
(B) The flux waveform is improved with reduction in harmonics.
(C) The inequality of air flux on the top and bottom halves of armature is
removed.
(D) A counter e.m.f. is induced in the coil undergoing commutation.

1 Answer

Answer :

Ans: D
Counter e.m.f is produced, it neutralizes the reactive emf.

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