Self-Sensing Amb With Compensation Of Non-Linear Magnetic Effects

This paper investigates the possibility to bring selfsensing active magnetic bearings to industrial application. A self-sensing active magnetic bearing is realized on an industrial prototype based on current amplitude modulation approach using a PWM amplifier. The performance limitations are investigated to identify the possible applications for this technology. This paper proposes a compensation of magnetic material permeability, which depends on the low frequency component of the current. The compensation is implemented using an approximated static permeability curve. Measurements were realized using a small industrial compressor prototype and applying the position estimator to one axis of one radial bearing. The estimated position was compared to the measured position obtained from a reference sensor.