Rotor Position Extraction of Dual Induction Motors at High Loads using Intermodulation Saliency

Abstract

Induction motors often show several spatial saliencies that can be extracted via pulse excitation and current response analysis in order to obtain a control signal (rotor flux angle or rotor position), eliminating thus the need for a shaft encoder. The most common saliencies used for rotor flux or position estimation are the magnetic saturation and rotor-slotting. However, both saliencies can face stability issues when motor is operated at very high loads. In this work, intermodulation saliency is employed for rotor position estimation for a dual traction motor drive operating at heavy loads. Highly precise rotor position estimation will be verified by experimental results.