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This focuses on the electrical machine design for a 7000 HP synchronous drive system using high-field permanent magnet (PM) motors for retrofit of a hybrid electric drive to the U.S. Navy DDG-51 FLT 3 ship. A dual system is described which has each module rated at 3500 HP, 6000 rpm and connected to the output propeller shaft through a two-stage gearbox. The system is intended to operate at 12 knots or lower speed allowing the main LM-2500 gas turbine main propulsion drive to be powered down and saving 15-17% in propulsion energy. In the hybrid mode, electrical power is furnished from the ship's 450 Volt 60 Hz electrical bus and converted to 200 Hz variable frequency through four IGCT based bi-directional converters to each drive motor. Aspects of the PM machine design which are special to this system include the use of 16-phase windings for lower harmonic content, larger damper winding arrangements and high strength rotor magnet containment. The PM stator contains a rapid internal fault detection (IFD) system for 1/4 cycle isolation of winding faults. Liquid-cooled machine designs with power density in the range of 6.0 to 12.0 kW/kg are shown. The overall system produces a total harmonic distortion of about 1.0% at the 450 Volt terminals at partial or full load in both motor and regeneration modes.