An Observer of Induction-Motor-State Variables Based on the Luenberger Algorithm with a Sliding-Mode System

A method for synthesizing an induction-motor-state observer based on the Luenberger algorithm operating in the sliding mode has been developed. An algorithm for determining the rotational frequency, flux-linkage modulus, and rotation angle of the rotor of an induction motor has been synthesized, characterized in that the determination of immeasurable motor coordinates is characterized by an increased accuracy of calculated variables in static and dynamic operating modes while maintaining the stability of the observer operation with changing active motor stator and the rotor resistances. A mathematical model of the observer has been developed, and simulation studies showing the operability of the proposed algorithm for determining immeasurable variables of an induction motor have been performed.