Sensorless position detection in permanent magnet drives

This presentation is concerned with a novel method of estimating rotor position from measurements of voltage and current at the terminals of an electrical machine. The method is potentially valuable in eliminating the need for a discrete position sensing element in the broad class of rotor position-switched electric drives. The estimator can be used in drives based on different types of motor e.g. switched reluctance motors or permanent magnet motors with sinusoidal or nonsinusoidal back EMF waveforms