The introduction of interpoles in between the main poles improves the performance of DC machines because:

The introduction of interpoles in between the main poles improves the performance of DC machines because: (A) the interpole produces additional flux to augment the torque developed (B) the flux waveform is improved with reduction in harmonics (C) the inequality of air flux on the top and bottom halves of the armature is removed (D) a counter emf is induced in the coil undergoing commutation
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The introduction of interpoles in between the main poles improves the performance of DC machines because: a counter emf is induced in the coil undergoing commutation

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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.

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

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