Advantages
- Absence of in-rush starting current
- Availability of full rated torque at starting
- High line power factor
- Absence of line current harmonics
- Smooth and wide range of speed control
Disadvantages
- Reduced efficiency because of the slip energy is wasted in the rotor circuit resistance
- Speed changes very widely with load variation
- Unbalance in voltages and current of rotor circuit resistances are not equal.