Sensorless control for induction motor drives based on new speed identification scheme

A sensorless controller, which is based upon the proposed synchronous speed identification scheme for induction motor drives, is presented in the paper. In comparison with previous results, which involve temperature-sensitive parameters including rotor and/or stator resistors, the proposed MRAS synchronous speed identification scheme requires neither rotor time constant nor stator resistance in both reference and adjustable models. It is shown that the new sensorless controller for induction motor drives consists of feedforward control of stator voltage and the new MRAS synchronous speed identification scheme, and does not invoke rotor resistance and voltage sensors. Simulation and experimental results are presented to confirm the theoretical analysis.