AC Synchronous Motor
An AC synchronous motor is a motor driven by alternating current (AC) in which the motor rotor spins at a multiple of the line frequency and the number of pairs of poles that create the magnetic field. Unlike an induction motor, a synchronous motor has zero slip associated with its operation. Syncronous motors are constant-speed motors and are therefore very efficient at converting AC power to mechanical work. The two types of AC synchronous motors are nonexcited and DC-excited.
