Analysis of Specific Load Capacity of Radial Hybrid Magnetic Bearing

Abstract:

This paper proposes a method based on vector calculation of flux density to evaluate the specific load capacity (SLC) of radial hybrid magnetic bearing (RHMB). The vector sum of the flux densities generated by the permanent magnet and the control current is calculated in this method, and then the functional expression of the SLC is built up via the flux densities. The influence of outer rotor diameter, fraction of circumferential rotor surface covered by poles and the length of the air gap are analyzed. It turns out that the SLC decreases with the maximum force of the bearing, and increases first and then decreases with the increase of pole area and length of the air gap. The maximum attainable SLC for RHMB of all sizes does not vary substantially from 23:1. The results of the analysis provide basis for the prediction of volume and mass for the RHMB in application.

• Periodical: Advanced Materials Research (Volume 668)
• Pages: 485-489
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.668.485
• Online since: March 2013
• Authors: Chun E Wang, Jian Cheng Fang
• Keywords: Functional Relationship, Permanent Magnet Biased, Radial Magnetic Bearing, Specific Load Capacity, Vector Calculation of Flux Density

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