A Rotor Parameter Identification Scheme for Vector Controlled Induction Motor Drives

A rotor parameter identification technique for the purpose of updating the control gains of an induction motor vector controller is described. The approach utilizes the current source nature of a current regulated PWM inverter by injecting a prescribed negative sequence current perturbation signal. The corresponding negative sequence voltage is sensed and decomposed into its d and q components. By injecting the signal at two widely separated frequencies (one perhaps dc) it is shown that the rotor resistance can be uniquely derived. Verification of the validity of the technique is obtained by a full scale simulation of a vector controlled induction motor drive.