Analysis of magnetic bearing using inductive levitation by relative motion between magnet and conductor

• Published in: Electrical engineering in Japan Vol. 166; no. 4; pp. 80 - 87
• Main Authors: Takanashi, Takeshi, Matsuya, Yuji, Ohtsuka, Yusuke, Nishikawa, Masahiro
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01-03-2009
• Subjects: braking torque; eddy current; electromagnetic induction; finite element method; magnetic bearing; restoring force
• ISSN: 0424-7760; 1520-6416
• DOI: 10.1002/eej.20652

In chemical plants, an anticorrosion magnetic drive pump is commonly used to deliver corrosive chemical liquids because of its high anticorrosion performance. However, when bubbles enter the chemical pump and accumulate between the shaft and the bearing, the shaft is often broken by thermal shock. The magnetic bearing which holds the rotor in noncontact has the advantage of avoiding thermal shock and keeping the rotor in a stable state by restoring force induced from the eddy current in the conductor. A model of magnetic bearing was analyzed using the three‐dimensional finite element method. In this model, a restoring force of 68.6 N and a braking torque of 8.7 N‐m were found. The locus of the rotation axis was also estimated using a radial load and a drag coefficient. The rotor may be located inside the movable range. ©2008 Wiley Periodicals, Inc. Electr Eng Jpn, 166(4): 80–87, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20652