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arXiv · 2202.04547

Self-Sensing Hysteresis-Type Bearingless Motor

Laura Homiller·Lei Zhou
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Abstract

Bearingless motors use a single stator assembly to apply torque and magnetic suspension forces on the rotor, making these machines compact with frictionless operation and thus well suited to high-speed applications. One major challenge that prevents wide usage of bearingless motors is the need for air-gap position sensors, which are typically expensive. Here we present a method to estimate the radial position of a hysteresis-type bearingless motor using the inductance variation of the stator coils amplified by an injected high-frequency signal. We have carried out finite element (FE) simulations to demonstrate its feasibility, and have constructed a prototype self-sensing bearingless motor for experimental validations.

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Laura Homiller, Lei Zhou. 2022-02-09. Self-Sensing Hysteresis-Type Bearingless Motor. https://arxiv.org/abs/2202.04547

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