Which of the following devices can be used as a phase advancer?
Right Answer is:
Synchronous motor working at leading power factor
This is one of the methods of power factor improvement it is a simple AC exciter that is connected to the main shaft of the motor and operates with the motor’s rotor circuit for power factor improvement. A synchronous motor working at the leading power factor can be used for power factor improvement of the induction motors. Hence the synchronous motor is working as a phase advancer.
- Phase advancer is used to improve the power factor of induction motors in industries.
- As the stator windings of the induction motor take a lagging current of 90° out of phase with Voltage, therefore the power factor of the induction motor is low.
- If the exciting ampere-turns are excited by an external AC source, then there would be no effect of exciting current on stator windings. Therefore the power factor of the induction motor will be improved. This process is done by Phase advancer.
Advantages of phase advancer:
- The phase advancer can be easily used where the use of synchronous motors is Unacceptable.
- Lagging kVAR (Reactive component of Power or reactive power) drawn by the motor is sufficiently reduced because the exciting ampere-turns are supplied at slip frequency.
Disadvantage of phase advancer
Using Phase advancer is not economical for motors below 200 H.P. (about 150kW).