Adaptation of stator and rotor resistances for the vector control of induction motors: A method based on reduced order current observer

This paper deals with the parameter adaptation problem of induction motors. It is well understood that the resistances of the stator and the rotor vary significantly in continuous operation. So, to prevent control performance degradation due to parameter error of the induction motor, online parameter adaptation is required. This paper proposes a new method, which is composed of two parts: A stator current observer and a parameter updating law. An outstanding feature of this method is that the rotor flux observer is not used. Instead, the flux reference value is used in the stator current observer which greatly simplifies the implementation. Simulations show that this method works satisfactorily.