Design and Analysis of an Advanced Dual-Mode Generator and Flywheel Energy Storage Unit
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.