Online Identification of Mutual Inductance of Induction Motor without Magnetizing Curve

This paper presents two easy-to-implement methods for online identification of the mutual inductance of induction motors without magnetizing curves. The first one uses the algorithm of a model reference adaptive system. The voltage model in a stationary reference frame is employed as a reference model as it is little affected by the variation of mutual inductances. The current model is used as an adaptive model as it is sensitive to the variation of mutual inductances. The second method is an open-loop method by calculating reactive power of the motor based on the steady-state voltage model in a rotating reference frame. As the reactive power and stator inductance are approximately linear, this method is easy to implement. Simulation results demonstrate that the steady-state errors caused by the mismatch of mutual inductance used in the controller and that of the motor are reduced by the proposed identification methods.