New technology for speed control of wound rotor motors

Abstract

PWM drive technology can be applied to wound rotor motors for adjustable speed operation as slip power recovery (SPR) drives. The PWM converter implementation of the SPR control approach overcomes the disadvantages of older current source SPR drives and adds new capability. While the application to wound rotor motors is new, the PWM drive technology is well-proven in powering low voltage (690 Vac and lower) squirrel cage induction motors in many applications. This paper describes the PWM SPR drive and how it is applied to the wound rotor motor.