Design, Fabrication, and Analysis of a Passively-Constrained Flywheel Energy Storage Device

Abstract

The aim of this project is to design, construct, and test a prototype small-scale, passively-constrained flywheel energy storage device. Flywheel energy storage is not a new concept. However, most modern flywheel energy storage devices are limited to large grid-scale operations. At this size, the use of actively-controlled electromagnetic bearings is effective in keeping the shaft and flywheel constrained and rotating with minimal friction and wear. For smaller-scale applications, however, the energy required to run the electro-magnets and control circuits becomes a large power drain, decreasing the system's ability to store energy in the long term. This project explores a simpler, more economical version of flywheel energy storage for use at smaller-than-traditional scales, based on the use of passive permanent-magnet bearings. Firstly, a passively-constrained flywheel energy storage system is designed. Secondly, the device is constructed. Thirdly, it is tested for properties of angular velocity persistence, maximum speed, and mechanical wear. Lastly, the performance is analyzed and suggestions are made for future devices of this type.