Applications of Synchronous Motors

Synchronous Motors are used in the following situations
  1. Applications which require constant Speed
  2. Applications which require load as well as power factor improvement
Synchronous Motors are used in applications which require constant speed.  Examples can be escalators which need to rotate at a constant speed as people get in and get out.  In industries, synchronous motors are used in systems which have to operate in synchronism such as in bottling plants, in robotics and in conveyors. 

Fractional Synchronous motors are used for small applications such as in microwaves, electric clocks and in data storage devices.  Fractional Synchronous motors do not have wound excitation system.  The rotor contains permanent magnets which run in synchronism with the stator. 
Synchronous Motors for Power Factor Correction.

Synchronous Motor operated in an overexcited condition can be used for power factor correction.  The overexcited synchronous motor draws active power from the grid and supplies reactive power.  This helps improve the power factor of the system.  A motor run in this manner is called a Synchronous Condenser