Basic Electrical and Electronics
INDUCTION MOTOR
INDUCTION MOTOR
 In olden days DC machines are widely used due to its
smooth speed control and production of high starting
torque
 After few decade AC Machines replaced DC machines
due to following reasons
HISTORY
INDUCTION MOTOR
 Availability of AC supply ( Generation is AC Supply)
 AC Machines are simple and rugged constructions
 High Efficiency and reasonably good power factor
 High reliability
 Design and maintenance cost is Low
 Simple starting arrangement
Advantages of AC Machines over DC
Machines
INDUCTION MOTOR
 it works on the principle of Induction so called
Induction motor
WHAT IS INDUCTION
 There is no electrical connection from main supply to
rotor winding, stator winding is directly connected to
AC source, where as rotor winding receives Energy
from stator by means of INDUCTION
Working Principle of Induction motor
INDUCTION MOTOR
 Induction motor consist of two parts
 Stationary part known as STATOR
 Rotating part known as ROTOR
 And these two are separated from each other by
small air-gap (about 0.4 mm to 4 mm)
Construction
INDUCTION MOTOR
 iron (or) steel yoke (frame)
 Hollow, cylindrical core made of silicon steel with
laminations
 Slots on the inner periphery of the laminated core
 Insulated conductor ( called stator winding)
 Star connected
 Delta connected
Construction of stator
INDUCTION MOTOR
Construction of stator
INDUCTION MOTOR
 Hollow, cylindrical core (slotted on outer periphery)
 shaft
 Conductors ( called rotor winding)
Construction of Rotor
INDUCTION MOTOR
Depending on the winding connections rotors are of two
types
 Squirrel cage Rotor
 Wound (or) Slip ring rotor
types of Rotor
INDUCTION MOTOR
 Laminated cylindrical core
 having parallel slots on its outer periphery
 Conductor or winding
 which is placed in each slot
 End rings
 All these conductors joined at each end
by metal rings called end rings as shown
 Equivalent circuit
Squirrel cage Rotor
INDUCTION MOTOR
Squirrel cage Rotor
INDUCTION MOTOR
 Laminated cylindrical core
 having a 3-phase star winding
 One side of winding short circuited and
other End connected to 3 slip ring
 Brushes
 Each slip ring is connected to brushes
Slip Ring Rotor
INDUCTION MOTOR
Slip Ring Rotor
INDUCTION MOTOR
Slip Ring Rotor
a
a’
Single N turn coil carrying current i
Spans 180o elec
Resultant flux
Principle of operation
Single N turn coil carrying current i
Spans 180o elec
b'
b
Resultant flux
Principle of operation
Single N turn coil carrying current i
Spans 180o elec
c'
c
Resultant flux
Principle of operation
3-PHASE SINUSOIDALLY DISTRIBUTED WINDINGS
WAVE SPACE
DISTRIBUTIONS
INDUCTION MOTOR
 Depending upon the rotor connections induction
motors are two types
 Squirrel cage induction motor
 Slip ring induction motor
Types of INDUCTION
MOTORS
INDUCTION MOTOR
 The rotor winding is short circuited at each end
by metal rings called end rings
 The motor which is designed with squirrel cage
rotor called squirrel cage induction motor
SQUIRREL CAGE INDUCTION
MOTOR
INDUCTION MOTOR
 One side of the windings are short circuited and
other ends are brought out and connected to slip
rings (mostly star connected)
 The motor which is designed with slip ring rotor
called slip ring induction motor
SLIP RING INDUCTION
MOTOR

INDUCTION MOTOR PPT.ppt

  • 1.
    Basic Electrical andElectronics INDUCTION MOTOR
  • 2.
    INDUCTION MOTOR  Inolden days DC machines are widely used due to its smooth speed control and production of high starting torque  After few decade AC Machines replaced DC machines due to following reasons HISTORY
  • 3.
    INDUCTION MOTOR  Availabilityof AC supply ( Generation is AC Supply)  AC Machines are simple and rugged constructions  High Efficiency and reasonably good power factor  High reliability  Design and maintenance cost is Low  Simple starting arrangement Advantages of AC Machines over DC Machines
  • 4.
    INDUCTION MOTOR  itworks on the principle of Induction so called Induction motor WHAT IS INDUCTION  There is no electrical connection from main supply to rotor winding, stator winding is directly connected to AC source, where as rotor winding receives Energy from stator by means of INDUCTION Working Principle of Induction motor
  • 5.
    INDUCTION MOTOR  Inductionmotor consist of two parts  Stationary part known as STATOR  Rotating part known as ROTOR  And these two are separated from each other by small air-gap (about 0.4 mm to 4 mm) Construction
  • 6.
    INDUCTION MOTOR  iron(or) steel yoke (frame)  Hollow, cylindrical core made of silicon steel with laminations  Slots on the inner periphery of the laminated core  Insulated conductor ( called stator winding)  Star connected  Delta connected Construction of stator
  • 7.
  • 8.
    INDUCTION MOTOR  Hollow,cylindrical core (slotted on outer periphery)  shaft  Conductors ( called rotor winding) Construction of Rotor
  • 9.
    INDUCTION MOTOR Depending onthe winding connections rotors are of two types  Squirrel cage Rotor  Wound (or) Slip ring rotor types of Rotor
  • 10.
    INDUCTION MOTOR  Laminatedcylindrical core  having parallel slots on its outer periphery  Conductor or winding  which is placed in each slot  End rings  All these conductors joined at each end by metal rings called end rings as shown  Equivalent circuit Squirrel cage Rotor
  • 11.
  • 12.
    INDUCTION MOTOR  Laminatedcylindrical core  having a 3-phase star winding  One side of winding short circuited and other End connected to 3 slip ring  Brushes  Each slip ring is connected to brushes Slip Ring Rotor
  • 13.
  • 14.
  • 15.
    a a’ Single N turncoil carrying current i Spans 180o elec Resultant flux Principle of operation
  • 16.
    Single N turncoil carrying current i Spans 180o elec b' b Resultant flux Principle of operation
  • 17.
    Single N turncoil carrying current i Spans 180o elec c' c Resultant flux Principle of operation
  • 18.
  • 19.
  • 20.
    INDUCTION MOTOR  Dependingupon the rotor connections induction motors are two types  Squirrel cage induction motor  Slip ring induction motor Types of INDUCTION MOTORS
  • 21.
    INDUCTION MOTOR  Therotor winding is short circuited at each end by metal rings called end rings  The motor which is designed with squirrel cage rotor called squirrel cage induction motor SQUIRREL CAGE INDUCTION MOTOR
  • 22.
    INDUCTION MOTOR  Oneside of the windings are short circuited and other ends are brought out and connected to slip rings (mostly star connected)  The motor which is designed with slip ring rotor called slip ring induction motor SLIP RING INDUCTION MOTOR