Rotor Flux Observer in Pseudo - Sliding Mode for Vector Controlled Induction Motor Drives

A kind of speed sensorless sliding - mode observers for induction motors has been developed. In this paper a new topology of such observer is investigated in order to determine its feasibility, robustness to parameter changes and practical applicability on digital signal processor. The positive feature of the proposed scheme is that it doesn´t require the rotor speed feedback or adaptation, only measured variables such as stator current and DC voltage are required. Experimental results on DSP TI LF2407A, presented in the end of the paper show good correspondence with proposed theory.