Author: Scott Davis

Publisher:

Published: 1997

Total Pages:

ISBN-13:

"The single-phase induction motor (SIM) is one of the most common types of rotating machinery available due to the single-phase AC nature of commercial and residential power supplies. A major problem associated with this type of machine is that, unlike three-phase induction machines, no starting torque is provided by the magnetic flux rotating inside the machine. Many methods have been devised to overcome this problem, most of which revolve around changing the phase difference between the main and auxiliary phase windings. The windings in a SIM are the components that enable the motor to rotate, in that the current flowing through them creates a force, and this force turns the rotor. The phase difference between the main winding and the auxiliary winding creates a rotating stator flux, which in turn induces a torque in the rotor. Present methods have the problems of either inefficient running characteristics, starting characteristics, or expensive switching gear. The switching gear is used to disconnect the auxiliary phase once the motor is running. Certain motors have better characteristics than others, but the cost involved in obtaining a machine with good characteristics in all of the problem areas is relatively large. " -- Abstract/Synopsis.