Describe the different
types of single-phase induction motor.
Types of single-phase induction motor
Split phase induction motor
Capacitor start induction run motor
Shaded pole motor
Repulsion motor: (1) Compensated repulsion motor (2) Repulsion start induction run motor and (3) Repulsion induction motor
AC series motor
Unexcited synchronous motor: (1) Hysteresis motor and (2) Reluctance motor
Which type of construction the single-phase induction
motor consists of?
The single-phase induction motor consists of
Stator : It
consists of starting and running winding. Both windings are placed 900
with respect to each other.
Rotor : It
is squirrel cage type.
Centrifugal switch : It is provided in motor to cut out starting winding.
Give reason: The single-phase induction motor is not
self-starting.
Single phase induction motor not self-starting
The single-phase winding produces pulsating or alternating flux which
acts on the stationary squirrel cage rotor. This flux does not produce any
rotation therefore the single-phase induction motor is not self-starting. (The
forward and backward rotating torque in the single-phase induction motor is
equal and opposite at standstill therefore the net torque is zero.)
What is backward rotating slip of the induction motor
if the forward rotating slip is s?
2 – s
On which factor the starting torque of the split phase
induction motor depends?
The starting torque in the split phase induction motor is directly
proportional to sin α. (Where α is angle between starting winding current and
running winding current)
Describe the function of the centrifugal switch in the
single-phase induction motor.
Function of the centrifugal switch
The function of the centrifugal switch is to disconnect starting winding
from the main supply when the motor speed reaches 70 to 80% of the full load
speed.
Where the relay coil is connected in the split phase
induction motor?
The relay coil is connected is in series with main winding whereas the
pair of its contacts are connected in series with the starting winding.
Which winding has high resistance in the split phase
induction motor? Main winding or starting winding
The main winding of the split phase induction motor has high reactance
but low reactance whereas the starting winding has high resistance but low
reactance.
State the applications of the split phase motor.
Applications
Centrifugal pumps
Fans
Blowers
Washing machines
Duplicating machines
Oil burners
Refrigerators
Give reason: The split phase induction motor is
constant speed motor.
Speed Regulation
The speed of the
split phase induction motor varies about 2 to 5% between no load to full load
therefore it is called as constant speed motor.
How the phase split is
done in the capacitor start induction motor?
The phase split in the capacitor start induction motor is done by
connecting a capacitor is in series with the starting winding.
Which type of capacitor is
used in the capacitor start induction motor?
Short duty electrolyte capacitor
Which type of induction
motor has high starting torque, split phase or capacitor start induction motor?
Why?
High starting torque
The capacitor start induction motor has high starting torque as compared
to split phase motor because the angle between starting winding current and
running winding current is 800 in the capacitor motor as compared to
300 in the split phase motor.
Why the capacitor is
provided in series with starting winding in the capacitor start induction
motor?
Function of capacitor
To provide necessary phase difference between starting and running
winding.
It provides necessary high starting torque.
Describe the function of
capacitor in the capacitor start and capacitor run motor.
Function of capacitor
It increases the power factor
High efficiency
Overload capacity increases
Noiseless operation
Which motor works as
unbalanced two phase motor?
Single value capacitor run motor
Whether any centrifugal
switch is necessary in the single value capacitor run motor?
No
Which type of capacitor is
used in the single value capacitor run motor?
Continuous duty rating motor, Pyranol insulated foil paper capacitor
State the applications of
the single value capacitor motor.
Application
Induction regulator
Furnace control
Rheostat
Arc welding control
What do you mean by single
value capacitor motor and two value capacitor motor?
Single value capacitor motor
The single value capacitor motor is one in which one capacitor is used
during starting as well as running condition.
Two value capacitor motor
The two-value capacitor is one in which high value of capacitor is used
during starting condition and low value of capacitor is used during running
condition.
You may also like :
No comments:
Post a Comment