Question

What the purpose of a commutator in a dc generator

Answer 1

Answer:

Commutator acts as a reversing switch

Commutator and Brushes on DC Motor. To keep the torque on a DC motor from reversing every time the coil moves through the plane perpendicular to the magnetic field, a split-ring device called a commutator is used to reverse the current at that point.

In a DC generator, the emf induced in the armature coil is alternating in nature. Accordingly, the current flowing in the armature coil is also alternating current. Commutator reverses this current at the exact instant when the armature coil crosses the magnetic neutral axis. Therefore, the load (which is external to the generator) gets a unidirectional current or direct current.