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Abstract: Due to the nonlinear relationship between force and
current/displacement, the performance of active magnetic bearings (AMB)
system based on local linearization varies greatly as the operating
point of the spindle changes. The same stiffness and the same
displacement tracking performance are demanded for grinding spindle with
AMB especially when noncircular workpieces need grinding. The influence
of changing operating point on performance is presented theoretically
and proved with experiments. Linear compensation is adopted to realize
global linearization because of its simplify. Three linear compensation
methods: minimum flux (MIF), constant flux sum (CFS), constant flux
product (CFP) are compared in terms of power loss and dynamic
performance. The result shows that the power loss of MIF is least and
CFS behaves best dynamic performance. The performance of AMB system
based on global linearization is measured and almost the same result is
obtained despite the change of operating point.
Key words: Magnetic bearings(MB) Nonlinear Linearization Spindle
CLC No: TH133.3
Received
20010918, received in revised
form 20020118
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