Sliding Mode Observer Scheme for Induction Motor Control
Abstract A novel approach to the speed sensorless torque and flux tracking sliding mode control of induction motor is presented in the paper. The main contribution of the paper is a new structure of induction machine rotor flux observer aimed for the sensorless operation. Proposed approach addresses the problem sensorless induction machine servo-drive at both, low and high speed, where rapid speed changes can occur. The idea is realized by introducing an non-linear stator frequency dependant gain in the rotor flux observer and thus enabling the operation at low and high speeds. The adaptation algorithm for stator resistance is included. Observer is robust to the parameter uncertainties, especially to rotor resistance. The performance is investigated and verified with simulations and experiments.