摘要 |
<p>A system and a method of sensorless control for electrical drives with induction motors, exploiting a technique for the measurement of the amplitude and/or the angular position of the airgap flux without flux, speed or position sensors. Said measurement technique is based on the generation of a high frequency magnetic field which, by composing with the main magnetic field, produces a change of the saturation level, which, in turn, generates a modulation of the zero sequence components of the stator voltage and the stator current. Said modulation is used to evaluate the amplitude and/or the angular position of the main field. A distinctive feature of said measurement technique is that it allows a correct estimation of the amplitude and/or the position of the airgap flux, whatever is the frequency of the stator voltage, and particularly, at very low and zero frequencies. <IMAGE></p> |