Composite Flywheel Development for Energy Storage

Abstract

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Rotor Design for High-Speed Flywheel Energy Storage Systems

“…The rotation induced loading thus causes a mismatch in rotor growth creating tensile stresses in the radial direction. Since fiber composite rotors generally lack reinforcement in the radial direction, causing low strength transverse to the fiber direction, rotors are more likely to fail due to cracking of the polymer phase (delamination) rather than fiber breakage (Tzeng et al (2005)). A central part of rotor design is therefore the reduction of radial tensile stresses.…”

“…This effect may have a significant influence on the long-term stress state within the flywheel rotor. Tzeng et al (2005);Tzeng (2003) investigated this effect by transforming the thermoviscoelastic problem into its corresponding thermoelastic problem in the LAPLACE space. The resulting thermoelastic relationship is similar to Eq.…”

“…reference Tzeng (2003) for details. It was shown, however, by Tzeng et al (2005) that stress relaxation occurs when time progresses. Thus, the constraining state which has to be considered in the optimization procedure is the initial state so that effects of thermoviscoelasticity are not considered in the following.…”

Design and test of a 300Wh composites flywheel energy storage prototype with active magnetic bearings

“…The specific energy is proportional to the specific strength of materials. Therefore, the fiber-reinforced polymer composites with high specific strength are usually used as the rim materials [8]. The composite rim is attached to a metal shaft through a metallic web or spoke hub which compensates the deformation difference between the rim and the shaft under the high speed running condition.…”

Development of High-Performance CFRP Flywheel

“…to a lithium ion battery, which shows good performance among the chemical batteries. NASA intended to have flywheel battery in International Space Station (2), (3) . On the other hand, energy density per unit weight is prior to the lithium ion battery and long-term durability is still under discussion.…”