Fault-tolerant control of heteropolar magnetic bearings /

Flux coupling in heteropolar magnetic bearings permits remaining active coils to assume actions of failed coils to produce force resultants identical to the un-failed actuator. A distribution matrix of voltages which consists of a redefined biasing voltage vector and two control voltage vectors can...

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Bibliographic Details
Main Author: Na, Uhn Joo, 1967-
Format: Thesis Book
Language:English
Published: [Place of publication not identified] : [publisher not identified] ; 1999.
Subjects:
Online Access:http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=731686181&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD
Description
Summary:Flux coupling in heteropolar magnetic bearings permits remaining active coils to assume actions of failed coils to produce force resultants identical to the un-failed actuator. A distribution matrix of voltages which consists of a redefined biasing voltage vector and two control voltage vectors can be optimized in a manner that reduces the peak flux density. An elegant optimization method for calculating distribution matrices by using Lagrange Multiplier is presented. The distribution matrices can also be optimized for a magnetic bearing with large path reluctantly by using weighted flux density Euclidean norm. Position stiffnesses and voltage stiffnesses are calculated for the fault-tolerant magnetic bearings. Simulations show that fault-tolerant control of the multiple poles failed magnetic bearings with a flexible rotor can be achieved with reduced load capacity. Fault tolerant control of a magnetic bearing with grouped currents is developed. Hardware requirements for the fault tolerant control can be considerably reduced by using this control scheme with grouped currents.
Item Description:Vita.
"Major Subject: Mechanical Engineering".
Physical Description:xxi, 149 leaves : illustrations ; 28 cm.
Issued also on microfiche from University Microfilm Inc.
Bibliography:Includes bibliographical references (leaves 138-139).