A Variable-Speed Reversible Drive Using an Induction Motor

This paper describes a drive in which a wound-rotor induction motor is supplied through a static-magnetic power modulator. The drive provides accurate, continuously variable control of speed at any setting up to synchronous speed in either direction of rotation. Other features of the drive are its low-speed regulation, its provision for acceleration and braking at controlled torque, with nearly linear transient response, low cost, and high reliability.