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dc.contributor.authorMarshall, Jeremy Ten_US
dc.date.accessioned2001-05-09en_US
dc.date.accessioned2014-03-14T20:35:45Z
dc.date.available2004-05-09en_US
dc.date.available2014-03-14T20:35:45Z
dc.date.issued2001-05-08en_US
dc.date.submitted2001-05-09en_US
dc.identifier.otheretd-05092001-155021en_US
dc.identifier.urihttp://hdl.handle.net/10919/32410
dc.description.abstractActive magnetic bearings (AMBs) have the ability to act concurrently as support bearings and as load sensing measurement tools. Previous work in the area of AMB force measurement has relied upon basic magnetic equations requiring knowledge of coil currents and air gap lengths. Some researchers have utilized magnetic flux probes to eliminate the need for air gap measurements, but these are limited by physical size constraints and require complex hardware. This thesis presents a new method for measuring forces with AMBs that utilizes multiple current pairs with no gap measurement to provide accurate and precise force predictions. Previous methods for force measurement with AMBs rely on the controlled environment of a laboratory setting for accurate measurements. The goal of this work is to develop a robust force measurement procedure for use in industrial and field applications, as well as the laboratory. The harsh environment of a factory floor makes air gap measurements difficult, which limits the use of current-based force equations. Additionally, the flexibility of AMB-equipped thrust measurement systems (TMSs) to measure many types of forces with little to no reconfiguration or calibration makes them appealing. The multi-point method provides predictions of both shaft force and rotor position using only current pairs without air gap measurements. Static and dynamic load scenarios were investigated to determine the feasibility of this new approach to force measurement. For both, the effects of bearing load and rotor position within the bearing were analyzed. Under dynamic loading, different amounts of unbalance as well as various rotor speeds were used to provide multiple test cases. The multi-point predictions of rotor position were analyzed and compared with the measured rotor positions. It was shown that this new multiple-point method for measuring bearing loads with AMBs provides equivalent or better force predictions to analogous single-point methods for static loads while eliminating the need for measuring rotor position.en_US
dc.publisherVirginia Techen_US
dc.relation.haspartthesis.pdfen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.subjectforce measurementen_US
dc.subjectactive magnetic bearingsen_US
dc.subjectmultiple pointen_US
dc.titleA Multi-Point Measurement Technique for the Enhancement of Force Measurement with Active Magnetic Bearings (AMB)en_US
dc.typethesisen_US
dc.contributor.departmentMechanical Engineeringen_US
thesis.degree.nameMaster of Scienceen_US
thesis.degree.levelmastersen_US
thesis.degree.grantorVirginia Polytechnic Institute and State Universityen_US
dc.contributor.committeechairKasarda, Mary E. F.en_US
dc.contributor.committeememberKirk, R. Gordonen_US
dc.contributor.committeememberLeo, Donald J.en_US
dc.identifier.sourceurlhttp://scholar.lib.vt.edu/theses/available/etd-05092001-155021/en_US


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