Answer / vijayan

The core is laminated to minimize the eddy current losses
in ac circuits. The voltage applied in dc machine is dc,so
there is no eddy current losses, no need of laminations.

Answer / raja

I support answer 1. But in detail. The flux in the stator of
DC machine (Yoke, poles) is not a time varying one. So it
can't produce any induced emf in those structures. In turn
there is no possibility to have eddy current. And since
there is no reversal of pole there is no possibility of
hysteresis loss also. In turn there is no need to laminate
the core.

Answer / althaf

the voltage induced in the armature conductors is ac,even though it is a dc machine.so the core is to be laminated

Answer / s.sakthivel

(1) to develop the residual magnets


(2) it is act as a permanent pole compare then AC supply pole so we are not laminated stater pole

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