Thesis (M.S., Electrical and Computer Engineering)--University of Idaho, June 2014 | The University of Idaho Flywheel Energy Storage System (UIFESS) requires sensors and power electronics for successful operation. The UIFESS contains a Field Regulated Reluctance Machine (FRRM) to rotate the flywheel and an integrated active magnetic bearing to provide air gap control for the flywheel. The power electronics enable air gap control and rotation of the flywheel. Major hardware components required for control include eddy-current displacement sensors, current sensors, microcontrollers, and power amplifiers. Each element of the power electronics is selected and interfaced with one another. Analysis of the power electronic elements is presented. Sensor signal conditioning topologies are designed and implemented. Multiple printed circuit boards are designed using mixed-signal design principles and populated to aid in interfacing the hardware. Determination of the maximum rotational flywheel speed is discussed. An investigation on the hardware requirements to achieve a rotational speed of 500,000 rotations per minute is conducted.