High voltage stator for a flywheel energy storage system

The University of Texas at Austin Center for Electromechanics (UT-CER;I) has designed and conducted component test/development for a flywheel energy storage system for pulsed loads and mobility load leveling in a tactical vehicle. Performance goals of this machine dictate that the stator windings will see continuous voltages of 6.7 kV and spikes to 10 kV. To manage the thermal leeds produced by the intermittent 5 MW output pulses, and continuous 350 kW duty the generator is cooled by oil at a maximum temperature of 90 degrees C, UT-CEM designed and developed a novel insulation system and dual coolant passage arrays for the stator. Design performance was verified in laboratory prototype testing. This paper summarizes design goals, analysis, and mockup testing of the motor-generator stator.