Answer / shy11am

synchronous motor

in synchronous motor the field is run at synchronous speed
with rotor speed.in this motor speed not depend on load.for
any load the speed will be constant.

Asynchronous motor

in Asynchronous motor the rotor run below the synchronous
speed.in this motor speed depend on load.for increase load
the speed will be change.

Answer / sunil guru

SYNCHRONOUS MOTOR

THIS MOTOR ROTATES AT SYNCHRONOUS SPEED AND NOT DEPENDENT
ON LOAD,
BY CHANGING THE EXCITATION OF THIS MOTOR P.F CAN BE MADE
LEADING OR LAGGING.
IT IS ALSO CALLED AS DOUBLY SILENT MOTOR BECAUSE IT RUNS ON
BOTH AC AND DC(FOR STARTING DC IS REQUIRED THEN NOT
REQUIRED)AND THE MOTOR IS NOT A SELF STARTING MOTOR.....
FOR STARTING IT REQUIRES DAMPER WINDING

ASYNCHRONOUS MOTOR

THIS MOTOR ALWAYS ROTATES AT A SPEED LESS THAN SYNCHRONOUS
SPEED
AND SPEED CHANGES DUE TO LOAD AT START THEN BECOME LIKE
CONSTANT
ONLY WORKS ON AC SUPPLY
THIS MOTOR IS SELF STARTING.
AND ALWAYS RUNS ON LAGGING POWER FACTOR

Answer / abhishek goyal

Basic diff is SLIP factor. In syc motor slip is less than
the asyn motor (Induction motor). because of that in syc
motor rotor speed is equal to stator speed or emf. In
induction motor rotor speed is less than the stator field or
emf. so it run slow.

sy motor: not effect on load
ay motor: effect on load

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