#Ac unity sync points generator

Motor action occurs if the field poles are 'dragged behind the resultant air-gap flux by the retarding torque of a shaft load'.

#Ac unity sync points generator

Generator action occurs if the field poles are 'driven ahead of the resultant air-gap flux by the forward motion of the prime mover'. Synchronous motors fall under the category of synchronous machines that also includes synchronous generators. Second, it can operate at leading or unity power factor and thereby provide power-factor correction. First, it is a highly efficient means of converting AC energy to work. In higher power industrial sizes, the synchronous motor provides two important functions. These machines are commonly used in analog electric clocks, timers and other devices where correct time is required. In the fractional horsepower range, most synchronous motors are used where precise constant speed is required.

Synchronous motors are available in self-excited sub-fractional horsepower sizes to high power industrial sizes. Small synchronous motors are used in timing applications such as in synchronous clocks, timers in appliances, tape recorders and precision servomechanisms in which the motor must operate at a precise speed speed accuracy is that of the power line frequency, which is carefully controlled in large interconnected grid systems. By contrast, the induction motor requires slip: the rotor must rotate slightly slower than the AC alternations in order to induce current in the rotor winding. The difference between the two types is that the synchronous motor rotates at a rate locked to the line frequency since it does not rely on current induction to produce the rotor's magnetic field. The synchronous motor and the induction motor are the most widely used types of AC motors. A synchronous motor is termed doubly fed if it is supplied with independently excited multiphase AC electromagnets on both the rotor and stator. The rotor with permanent magnets or electromagnets turns in step with the stator field at the same rate and as a result, provides the second synchronized rotating magnet field. Synchronous motors use electromagnets as the stator of the motor which create a magnetic field that rotates in time with the oscillations of the current. Small synchronous motor with integral stepdown gear from a microwave ovenĪ synchronous electric motor is an AC electric motor in which, at steady state, the rotation of the shaft is synchronized with the frequency of the supply current the rotation period is exactly equal to an integral number of AC cycles.