Page 667 - Basic Electrical Engineering
P. 667
8
Three-phase Induction Motors
TOPICS DISCUSSED
Basic principle of a three-phase induction motor
Constructional details
Rotating magnetic field
Synchronous speed
Slip speed
Rotor-equivalent circuit
Rotor current
Rotor frequency
Power-flow diagram
Torque
Torque-slip characteristics
Effect of change of rotor circuit resistance on torque-slip characteristics
Starting torque
Condition for maximum torque
Starting
Speed control
Losses
Efficiency
Applications
8.1 INTRODUCTION
Three-phase induction motors are used in many industrial applications such
as a drive motor. These motors are very rugged, and hence there is virtually
no maintenance required. Only three-phase supply is required for the stator.
