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Series
field winding
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Shunt
field winding
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The armature winding
is series with the field winding
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The armature winding
is parallel with the shunt field winding.
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|
As the series field
winding is connected in series with the armature winding, the series field carries
same current as that of armature winding.
|
As the shunt field
winding is connected in parallel with the armature winding, the voltage
across shunt field winding is same as the armature winding.
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The series winding
is designed with few turns of thick wires.
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The shunt field
winding is designed with large number of turns having thin wires.
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The resistance of
the series field winding is very low.
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The resistance of
the shunt field winding is very high.
|
|
The torque is
directly proportional to square of the armature current.
T α ΦIa
As Φ α Ia
T α Ia2
The
series motor would draw only 1.41 times full load current for the same amount
of torque. ( As
t α Ia2 )
|
The torque is
directly proportional to the armature current.
T α ΦIa
As Φ is almost
constant
T α Ia
If
twice the full load torque required at start, the shunt motor draws the twice
the full load current. (
As t α Ia )
|
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The starting torque
develop by series motor is high as compared to shunt motor for same amount of
armature current.
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The starting torque
develop by shunt motor is low as compared to series motor for same amount of
armature current.
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A
series motor respond by decreasing its speed with small increase in current
for a given load torque.
|
A
shunt motor holds its speed nearly constant with large increase in input
current for same amount of load torque.
|
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Variable speed motor
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Constant speed motor
|
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Applications
: Hoists
, Cranes
, Trolley cars
,Conveyors, Electric locomotives
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Applications
: Lathes
, Centrifugal pump
, Blowers, Machine tools
, Printing process
, Spinning machines,
Reciprocating
pump
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