This paper investigates combined radial axial magnetic bearing (CRAMB) technology as an enabling component for shafted bearingless motor systems. The unique requirements of high speed bearingless motors designed for significant power levels are used to guide a literature review on CRAMB designs. Fundamental bearing topology aspects are identified and compared. Based on the outcome of this review, a new CRAMB topology is proposed and developed to meet the needs of a bearingless motor. Key features of the proposed design include a three pole radial force stage (driven by a three phase motor drive) and utilization of an optimal bias flux that improves radial force density by approximately 15% (improved rotor dynamics). It is shown that compared to a conventional four pole side-by-side CRAMB, this topology decreases the bearing shaft length and requires two fewer power electronic switches (6 instead of 8).
|Original language||English (US)|
|Title of host publication||Proceedings - 2019 IEEE Workshop on Electrical Machines Design, Control and Diagnosis, WEMDCD 2019|
|Publisher||Institute of Electrical and Electronics Engineers Inc.|
|Number of pages||8|
|State||Published - Apr 2019|
|Event||2019 IEEE Workshop on Electrical Machines Design, Control and Diagnosis, WEMDCD 2019 - Athens, Greece|
Duration: Apr 22 2019 → Apr 23 2019
|Name||Proceedings - 2019 IEEE Workshop on Electrical Machines Design, Control and Diagnosis, WEMDCD 2019|
|Conference||2019 IEEE Workshop on Electrical Machines Design, Control and Diagnosis, WEMDCD 2019|
|Period||4/22/19 → 4/23/19|
Bibliographical noteFunding Information:
The authors would like to acknowledge the support of the Wisconsin Electric Machines and Power Electronics Consortium (WEMPEC). N. R. Hemenway is with the Department of Mechanical Engineering, University of Wisconsin, Madison, WI 53706 USA. H. Gjemdal is with the Department of Electric Power Engineering, NTNU, Trondheim N-7491 Norway. E. L. Severson is with the Electric and Computer Engineering Department, University of Wisconsin, Madison, WI 53706 USA (e-mail: firstname.lastname@example.org).
© 2019 IEEE.
- Bearingless motor
- High speed
- Magnetic bearing
- Magnetic suspension