Online Identification of Stator Transient Inductance in Rotor-Flux-Oriented Induction Motor Drive

In a rotor-flux-oriented induction motor drive, stator transient inductance is varied with the change of operating conditions. If the stator transient inductance is not tuned, the field orientation cannot be obtained. As a result, q-axis rotor flux does not become zero, and the performance is deteriorated. This paper shows the problems caused by the detuning of stator transient inductance and proposes a simple online tuning scheme of stator transient inductance for an indirect rotor flux-oriented induction motor drive. Stator transient inductance is estimated only by stator voltage and stator current. The proposed method is verified by simulation and experimental results.