· Its average speed is constant and independent of load
· It can be operated under a wide range of power factor, both lagging and leading.
· It required the dc excitation so it is a doubly excited machine,.
No speed control is possible.
· It’s used for supplying mechanical load as well as for power factor improvement.
Its torque is less sensitive to change in supply voltage.
· Breakdown torque is proportional to the supply voltage.
· It is more complicated and cost more comparatively.
- It has got self-starting torque and no special means is required for its starting.
- Its speed falls with the increase in load and less than synchronous speed
- It operate at only lagging power factor, which becomes very poor at light loads.Its requires no dc excitation so it’s a singly excited machine
- Its torque is more sensitive to change in supply voltage.Breakdown torque is proportional to the square of the supply voltage.
- It is more simple and cost less than Synchronous motor