what are the diffences between a synchronous and induction motor?
A synchronous motor operates with a winding in its rotor which is connected to an external resistor for speed control during start-up, while an induction motor, squirrel caged type has no external resistor. The rotor windings are short-circuited at the ends and is like a squirrel. The speed of a synchronous motor has no slippage. 2,poles-3600 rpm; 4-poles-1800 rpm; 6poles-1200 rpm while an induction motor has a slip speed, 2poles- 3540 rpm; 4 poles-1750 rpm; 6poles-1150 rpm.A synchronous motor always operates with carbon brushes, while induction motors may have none.Synchronous motors are usually rated at least 100Hp, while, induction motors may be rated in fractional Hp.
