Subject and UNIT: Electrical Machines II: UNIT III: a. Three Phase Induction Motor Engineering Electrical Machines - II
Thus when the slip of the induction motor is negative i.e. when the induction motor runs faster than synchronous speed, the induction motor runs as a generator called induction generator.
Three Phase Induction Motor
Subject and UNIT: Electrical Machines II: UNIT III: a. Three Phase Induction Motor Engineering Electrical Machines - II
This is the major advantage of slip ring induction motor that it gives high rotor resistance at starting and low rotor resistance at normal operating speed.
Subject and UNIT: Electrical Machines II: UNIT III: a. Three Phase Induction Motor Engineering Electrical Machines - II
The harmonics caused due to variation of air gap reluctance are called tooth or slot harmonics.
Subject and UNIT: Electrical Machines II: UNIT III: a. Three Phase Induction Motor Engineering Electrical Machines - II
The phasor diagram of loaded induction motor is similar to the loaded transformer.
Subject and UNIT: Electrical Machines II: UNIT III: a. Three Phase Induction Motor Engineering Electrical Machines - II
We have already seen that the induction motor can be treated as generalized transformer.
Subject and UNIT: Electrical Machines II: UNIT III: a. Three Phase Induction Motor Engineering Electrical Machines - II
The various stages in this conversion is called power flow in an induction motor.
Subject and UNIT: Electrical Machines II: UNIT III: a. Three Phase Induction Motor Engineering Electrical Machines - II
The various power losses in an induction motor can be classified as, i) Constant losses ii) Variable losses.
Three Phase Induction Motor
Subject and UNIT: Electrical Machines II: UNIT III: a. Three Phase Induction Motor Engineering Electrical Machines - II
Let us see the effect of change in voltage and frequency on the torque-slip characteristics of an induction motor.
Three Phase Induction Motor
Subject and UNIT: Electrical Machines II: UNIT III: a. Three Phase Induction Motor Engineering Electrical Machines - II
It is known that in slip ring induction motor, externally resistance can be added in the rotor. Let us see the effect of change in rotor resistance on the torque produced.
Induction Motor
Subject and UNIT: Electrical Machines II: UNIT III: a. Three Phase Induction Motor Engineering Electrical Machines - II
To compare the performance of induction motor with d.c. shunt and series motors, it is possible to plot speed-torque curve of an induction motor.
Three Phase Induction Motor
Subject and UNIT: Electrical Machines II: UNIT III: a. Three Phase Induction Motor Engineering Electrical Machines - II
The performance of the motor is sometimes expressed interms of comparison of various torques such as full load torque, starting torque and maximum torque.
Three Phase Induction Motor
Subject and UNIT: Electrical Machines II: UNIT III: a. Three Phase Induction Motor Engineering Electrical Machines - II
As the induction motor is loaded from no load to full load, its speed decreases hence slip increases.