Interactions dynamics between a satellite and onboard magnetically suspended flywheels
Conference Paper
Overview
Overview
abstract
This paper presents analysis and simulation results for the force-motion interactions that result from satellite attitude control via position, orientation and speed shifts of magnetically suspended flywheels or arrays of flywheels. The practical relevance of this study is the proposed use of high-speed, magnetically suspended flywheels for the dual service applications of integrated power and attitude control system (IPACS). This will extend previous IPACS studies which assume that the flywheels are suspended with bearings modeled as rigid or as simple linear springs. The flywheel configurations studies include a single, gimbal mounted flywheel with variable speed and orientation with respect to the satellite or a tetrahedral array of 4 flywheels with variable speeds and fixed orientations with respect to the satellite. Vernier attitude control for the satellite is actuated by translating or rotating the spinning element of the flywheel inside of the clearances of its auxiliary (backup) mechanical bearings. Large motion attitude control is actuated by either gimbal rotations of a single flywheel or by independent spin rate changes of fixed (non-gimbaled) flywheels in a tetrahedral array. Simulation models of the components in the magnetic suspensions are discussed along with the compensation stages required for stable control. Disturbances in the model include electromagnetic interference EMI, shaft motion sensing imperfections (runout) and imbalance. Simulation results include identification of limits for satellite angle slew rates and vernier control induced angle changes determined by component saturation in the magnetic suspension. A discussion of desirable design features for the flywheel magnetic suspension is presented based on the simulations. 2003 by Yeonkyu Kim.
