Because of their high efficiency and high speed, synchronous motors are well suited for________.

Because of high efficiency and high speed (above 600 rpm), synchronous motors are well suited for loads where constant speed is required such as blowers.

Other applications of centrifugal pumps, belt-driven reciprocating compressors, blowers, line shafts, rubber & paper mills etc.

Synchronous Motors

• ​​Synchronous motors are inherently not self-starting. They require some external means to bring their speed close to synchronous speed before they are synchronized. The speed of operation is in synchronism with the supply frequency and hence for constant supply frequency they behave as constant speed motors irrespective of load condition
• A synchronous motor can be used to compensate for voltage drop in constant voltage transmission by acting as a synchronous condenser. When the system voltage drops, the motor can be over-excited to generate reactive power, which helps to maintain the system voltage at the desired level. This method is often used in power systems to improve power factor and voltage regulation. 
• Synchronous motor finds applications where operating speed is less (around 500 rpm) and high power is required. For low power output below 40 kW in the medium speed range, the size, weight, and cost of the corresponding three-phase induction motor are very high. ​