Analysis and Simulation of Wound-Rotor Doubly-Fed Induction Machine

This paper analyzes the steady state characteristic of the wound rotor doubly fed induction machine when the rotor is excited with slip frequency. A motor model is also developed for conditions when the rotor excitation frequency doesn´t equal to the slip frequency. The analytical model is verified by simulation results of a dynamic model built in Simulink. The stability of the machine is also analyzed based on a simplified linearized model, it is proven that the machine is not stable or marginally stable without any feedback control. Simulation results of step torque change are also used to verify the analysis. A simple controller is designed to stabilize the motor.