Answer / k.rajmohan

All m/c generating AC power supply. The function of the
commutator to commutate ac power. Through brush we are
getting the Dc power.

Answer / neeraj insa

All m/c generating AC power supply in the universe except
battery.in the gen. we apply dc power on rotor which r
short ckt at ends(some times on stator also),that create a
magnetic field on rotor name north & south pole.as rotor
rotate than the magnetic field north pole cut by stator
conductor that produce +ve half cycle.as rotor move north
pole magnetic field cut by stator conductor,that create -ve
cycle.so in this whole process we get ac.The function of
the
commutator to convert ac into dc,becouse commutator is a
mech. rectifier.

Answer / vijay kumar surla

Yes a rotating machine can give DC output without commutator.Here the commutator is a mechanical rectifier.Instead of using commutator we can use electrical rectifiers (like full wave diode rectifiers) to convert AC to DC.

Answer / s.sivaranjani

According faraday's law of electromagnetic induction
whenever there is a chanage in flux linked with the coil ,
it will be induced by an e.m.f (volatge).
Induced volatge will be of same type as that of source(i.e
alternating).
In DC machine(i.e) generator, the elecromagnetic poles are
generated with DC supply.
Dc machine consists of two main parts 1.stator 2.rotor
stator - stationary part consists of Poles.(north & south)
Rotor is a rotating one.also called as armature.
Rotor is fed by meachinal input i.e angular rotation.
Initially the rotor with armature coils do not carry any
current.
Because of the maechanical input the armature starts to
rotate at the constant magnetic field.
Therefore the armature experiences chnage in flux.
Hence an emf will be induced in the armature according to
faraday's law.
The generated emf is AC type. In order to make it
unidirectional (i.e DC) an arrangement is needed.
The arrangement is called Commutator.
Along with commuatator brush assembly is required to take
out the DC supply.

Answer / vijay kumar surla

Yes a rotating machine can give DC output without
commutator.Here the commutator is a mechanical
rectifier.Instead of using commutator we can use
electrical rectifiers (like full wave diode rectifiers)
to convert AC to DC.

Answer / kumar.shyam1

here roatating machine may be synronous machine and dc
machine

in case of syncronous machine we use staionary armature and
roataing field to produce A.C
with th same construction production of d.c output is not
possible


in case of d.c machine we prefer roatating armature and
staionary field becasue to produce d.c out put
with a.c consturuction we can not produce becase it raises
comnutator problem for a.c to produce d.c

if we is a.c construction for d.c to produce a.c
genaration of higher voltages are not possible

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