A synchronous and synchronous motors are the two main categories of ac motors. The induction motor is a common form of asynchronous motor and is basically an ac transformer with a rotating secondary.

THE first edition of this work appeared in 1904. Since then remarkable advances have been made in electrical engineering. A foremost place in this progress must be given to electric motors, and more ...

Click to open image viewer. No extant maker's markings. Early single phase induction motor, built by Elihu Thomson in 1888. The frame is of circular construction and consists of laminated metal sheets ...

In this single phase induction motor, energy from the primary winding in yellow is coupled through a magnetic core to a rotary structure called a bobbin, which acts as a short circuited transformer ...