Operating characteristics of a 0.87 kW-hr flywheel energy storage moduleDiscussion is given of the design and loss characteristics of 0.87 kW-hr (peak) flywheel energy storage module suitable for aerospace and automotive applications. The maraging steel flywheel rotor, a 46-cm-(18-in-) diameter, 58-kg (128-lb) tapered disk, delivers 0.65 kW-hr of usable energy between operating speeds of 10,000 and 20,000 rpm. The rotor is supported by 20- and 25-mm bore diameter, deep-groove ball bearings, lubricated by a self-replenishing wick type lubrication system. To reduce aerodynamic losses, the rotor housing was evacuated to vacuum levels from 40 to 200 millitorr. Dynamic rotor instabilities uncovered during testing necessitated the use of an elastometric-bearing damper to limit shaft excursions. Spindown losses from bearing, seal, and aerodynamic drag at 50 millitorr typically ranged from 64 to 193 W at 10,000 and 20,000 rpm, respectively. Discharge efficiency of the flywheel system exceeded 96 percent at torque levels greater than 21 percent of rated torque.
Document ID
19860040126
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Loewenthal, S. H. (NASA Lewis Research Center Cleveland, OH, United States)
Parker, R. J. (NASA Lewis Research Center Cleveland, OH, United States)
Zaretsky, E. V. (NASA Lewis Research Center Cleveland, OH, United States)
Scibbe, H. W. (Goodyear Aerospace Corp. Akron, OH, United States)