How damper winding in synchronous motor suppress Hunting?
Answer Posted / iamdon
In synchronous machines, the damper winding is placed on
pole face of rotor which is short circuited at end.
When load on machine is suddenly changed, the rotor starts
oscillating (due to its inertia )about the new equilibrium
point.However the oscillation finally dies out because of
presence of damper winding.The oscillation is called
hunting.
During hunting,there is a relative motion between rotor
(damper winding)and synchronously rotating magnetic field.
So emf induces in the damper winding as per Faraday's law
and current flows in accordance with Lenz's law as long as
the relative motion exists.As we know,the effect will
always oppose the cause.Here effect is induced current in
damper winding and cause is relative motion.So induced
torque in damper winding acts in opposition to
instantaneous relative motion.
Author:arbelectbit@yahoo.com
Is This Answer Correct ? | 139 Yes | 11 No |
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