Research Investigation of Magnetic and Electric Forces for Rotating Shaft Suspension

摘要

Described are experimental efforts to achieve noncontacting confinement of rotating electrical machinery having radial air gaps. The approaches investigated included magnetostatic means, resonant electric and magnetic bearings, and electromagnets in high performance control systems. Both linear and nonlinear (dual-mode) controls were developed for nonminimum phase systems. Limitations and possible applications are outlined for the various bearings tested. Only one system achieved the goal of support of a 1 Hp. motor furnished by contractor. This system used servoed bipolar electromagnets and non-retentive rotors. It served as the basis for a conservative design for support of the SNAP II Combined Rotating Unit. Projected stiffness at 0.707 damping is 250,000 lbs/in. resulting in a whirl amplitude of 25 microinches and a total power expenditure of 675 watts. The special attributes of the magnetic thrust bearing are emphasized. (Author)