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Abstract: The relationships between dynamic stiffness properties and
PID parameters of active electrostatic bearing and rotor systems based
on a stiffness compensated model are investigated. The analytical and
experimental results via a three-degrees of freedom electrostatic
bearing supporting a spherical rotor demonstrated that the frequency
response curve of the bearing stiffness is in a bathtub shape with a
minimum value in intermediate frequency range. The dynamic stiffness is
mostly determined by controller parameters within the closed-loop
bandwidth of electrostatically levitated systems, while the stiffness
above the system bandwidth is determined by the inertial stiffness of
the rotor. As a result, the stiffness properties may be varied over a
certain range by changing the controller parameters within the stable
region.
Key words: Electrostatic bearing Dynamic stiffness Electrostatic
levitation PID control
CLC No: TH133.3
TN701.17
国防基础与应用研究“十五”预研(41309020)和河南省青年骨干教师资助项目. Received 20030221, received in
revised form 20030714
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