10. Which type of Induction motor is best for e.m.f injection method? Explanation: E.M.F injection method is used to control the speed of Induction motor. It is only applicable for WRIM because WRIM rotor consists of copper windings connected in star connection.
Which type of induction motor is best?
Three-phase squirrel-cage induction motors are widely used as industrial drives because they are self-starting, reliable and economical. Single-phase induction motors are used extensively for smaller loads, such as household appliances like fans.
Which is best method to stop the induction motor?
In an AC induction motor, when the AC voltage is removed, the motor will coast to a standstill over a period of time, since there is no induced field to keep it rotating. Since the coasting time may be unacceptable, particularly in an emergency situation, electric braking can be used to provide a more immediate stop.
Which of the method can be used for speed control of induction motor?
Thus, speed control of induction motor can be achieved by a total of five different methods: VVVF Speed Control. Pole Changing Method. Rotor Circuit Resistance Control.
What 3 things are needed for an induction motor to work?
A 3-phase induction motor includes two essential components namely the stator & the rotor. In this motor, the stationary part is the stator whereas the rotating part is the rotor. In this motor, the load is connected to the shaft. Three-phase armature winding can be wound over the stator.
What are the two types of induction motors?
Single-phase induction motors and three-phase induction motors are the two main types of induction motors. As their names imply, a single-phase induction motor is connected to a 1 phase AC power supply and a three-phase induction motor is provided with 3 phase AC power supply.
How can the RPM of induction motor be reduced?
Speed Control of Three Phase Induction Motor
- V / f control or frequency control.
- Changing the number of stator poles.
- Controlling supply voltage.
- Adding rheostat in the stator circuit.
Which braking is not suitable for motor?
In series motor back emf cannot exceed the supply voltage. So regenerative braking is not possible.
Which is the best braking method?
Explanation: Plugging is the best braking method among all braking techniques. In plugging the value of the armature current reverses and the mechanical energy is extracted. A very high braking torque is produced in case of plugging.