What are the differences between induction and synchronous motors? You just need to go through the following points-
- In Induction motor the torque has the property of self-starting; it means there is no requirement of any other mode for this. However, in Synchronous motors no self starting way is available and it requires an external means to start.
- No D.C excitation is required in induction motor and in synchronous motor D.C excitation is required.
- The speed in induction can be controlled to a very small extent, but you cannot control speed in Synchronous motor.
- The speed in induction will be less if the load gets heavier and along with that the speed is always below than synchronous speed.
In case of Synchronous motor, the speed is free from load and this has the constant speed.
- Lagging power factor is there to handle the load in induction motor and this factor is not good for light loads.
The wide range of power factor is there for lagging as well as leading in synchronous motors.
- The supply voltage change of induction torque is more sensitive, while this is also important to know that synchronous motors are less sensitive.
- In induction motors, Breakdown torque ∝ square of the Supply voltage
In synchronous motors, Breakdown torque ∝ the supply voltage
- The induction motor is very simple and less expensive than synchronous motors, so synchronous motors are more complicated and more expensive.
- The supply mechanical load is there only for induction motors. In Synchronous motors the improvement of power factor as well as supply mechanical load is employed.