Answer / janani venkatesan

Most of the alternators have thir pole shoes slotted to
receive copper bars of a grid or damper windings.Copper
bars are short circuited at both ends by heavy copper
rings.These DAMPERS are useful in preventing hunting(speed
fluctuations) in generators and are needed in synchronous
motors to provide starting torque.Under normal running
conditions, damper windings does not carry any current
because rotor runs at synchronous speed.They tend to
maintain balanced 3phase voltage under unbalanced load
conditions.

Answer / guest

it reduces the fluctuatation in any circuit

Answer / engineering.force

Damper winding is used in pole shoes of alternator. It
consists of short circuited copper bars. The question may
arise then how do they have potential difference when they
are short circuited ? The concept is of mutual induction.
Also they are used for the starting of the generator, and in
case of fluctuations of the rotor (called huntng of the
rotor) they will damp the hunting, that's why the name goes
damper winding.

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