A position sensorless induction machine drive for electric vehicle applications

The rotor speed is estimated for a position sensorless induction machine drive using a physical approach. This physical approach uses a frequency compensation scheme to estimate the rotor flux accurately at low speeds and subject to parameter variations. After background material is presented to explain the principles of the estimator, a computer simulation is conducted of a field oriented drive with the estimator. Based on the favorable results of the simulation, a laboratory investigation is conducted of the proposed drive.