A general adaptation mechanism and its applications to induction motor direct field oriented drives

In this paper, the authors present a general adaptation mechanism for parameter identification in adaptive observers, and its application to direct field oriented control (DFOC) systems using induction machines. The mechanism is derived using Popov's hyperstability theory and then the adaptive observer stability is proved in the general situation. From the general formula presented, one may directly obtain all the particular adaptation laws used for speed, rotor or stator resistance identification by estimation methods based on a reference model.