Difference Between Synchronous and Asynchronous Motor

Synchronous motor is a machine whose rotor speed and the speed of the stator magnetic field is equal. Asynchronous motor is a machine whose rotor rotates at the speed less than the synchronous speed. ... Synchronous motor requires an additional DC power source to initially rotate the rotor near to the synchronous speed.

1. What is difference between synchronous and induction motor?
2. Where is synchronous motor used?
3. What is synchronous speed?
4. What are the advantages of synchronous motor?
5. What are the main parts of synchronous motor?
6. Are brushless motors AC or DC?
7. Why is it called synchronous motor?
8. How does a synchronous motor start?
9. What is the working principle of synchronous motor?
10. What does asynchronous mean?

What is difference between synchronous and induction motor?

A three-phase synchronous motor is a doubly excited machine, whereas an induction motor is a single excited machine. The armature winding of the synchronous motor is energized from an AC source and its field winding from a DC source. The stator winding of Induction Motor is energized from an AC source.

Where is synchronous motor used?

In the fractional horsepower range, most synchronous motors are used where precise constant speed is required. These machines are commonly used in analog electric clocks, timers and other devices where correct time is required. In higher power industrial sizes, the synchronous motor provides two important functions.

What is synchronous speed?

: a definite speed for an alternating-current machine that is dependent on the frequency of the supply circuit because the rotating member passes one pair of poles for each alternation of the alternating current.

What are the advantages of synchronous motor?

Advantages of Synchronous Motor

• The advantage of using synchronous motor is the ability to control the power factor. ...
• Speed remains constant irrespective of the loads in synchronous motors. ...
• Synchronous motors are built with wider air gaps than induction motors which make them mechanically more stable.

What are the main parts of synchronous motor?

The stator and rotor are the two main parts of the synchronous motor. The stator is the stationary part, and the rotor is the rotating part of the machine. The three-phase AC supply is given to the stator of the motor.

Are brushless motors AC or DC?

Brushless DC motors are DC motors in the sense they are fed from a DC source. They use, however, an inverter (a type of power electronic converter) as an "electronic commutator" to provide an alternating current in accordance with the rotor position so that it can generate the torque.

Why is it called synchronous motor?

Therefore the rotor rotates at the same speed that of the rotating magnetic field. It is due to the reason the motor is called as synchronous motor. It is a constant speed motor because, despite the increase in load motor runs at the same synchronous speed.

How does a synchronous motor start?

The motor is first started as a slip ring induction motor. The resistance is gradually cut-off as the motor gains speed. When it achieves near synchronous speed, DC excitation is given to the rotor, and it is pulled into synchronism. Then it starts rotating as a synchronous motor.

What is the working principle of synchronous motor?

Working of synchronous motors depends on the interaction of the magnetic field of the stator with the magnetic field of the rotor. The stator contains 3 phase windings and is supplied with 3 phase power. Thus, stator winding produces a 3 phased rotating Magnetic- Field.

What does asynchronous mean?

1 : not simultaneous or concurrent in time : not synchronous asynchronous sound.