Authors: Dr. Joseph H. Beno, Dr. Hamid Ouroua, Mr. Scott Pish, Mr. Matt Tillman, Mr. Richard Hayes, Mr. John Herbst, Mr. Don Hoffman, Dr. John Heinzel

Abstract: With funding from the Office of Naval Research, the University of Texas has designed an advanced dual mode generator and flywheel energy storage unit that is capable of producing 7-12 MW peak power and 3-4 MW rms power; delivers 19kW-hr energy; integrates into a range of ship power system topologies and fits through a 26 inch hatch. The design employs a very high density inside-out rotor topology; can provide flexible mission support for pulse power, power quality, load leveling and ride-through during power outages; can be scaled down or up; and exhibits very long cycle life. Some key enablers developed in the this design effort that also apply to a wide range of very high power density generators include the use of recent advances in composite materials; development and testing of high speed permanent magnet cartridge for the rotor; inside-out magnetic bearing technology; and use of advanced rotor-safe life design practices. The paper will cover design challenges, bearing selection; bearing analysis; EM design; thermal design and analysis; the rotor-safe life design approach; stator design details; rotor design details; composite design details; risk areas and risk mitigation experiments. The paper will also compare the design to the state-of-the-art.