N13A-T028 TITLE: Hybrid, Ultra-High-Speed, High Efficiency, Power Dense, Electronically Controlled Energy Conversion Unit for Ship Systems, Unmanned Vehicles, and Robotics Applications

TECHNOLOGY AREAS: Air Platform, Ground/Sea Vehicles

OBJECTIVE: The objective of this topic is to push the speed limits of an ultra-high-speed energy conversion unit up to one million revolutions per minute (i.e. 1000 Krpm) with over 95% system efficiency utilizing advanced, high-speed power electronic switching technologies and control schemes.

DESCRIPTION: The Navy is embarking on an aggressive Power and Energy Program and a Next Generation Integrated Power System (NGIPS) for application on both shore based facilities and future surface ships and underwater vehicles. With the addition of alternative power generation technologies and the need to increase energy security to shore facilities, the Navy will benefit from technology solutions that can cost-effectively move this power from fuel to end use. Limited by the shipboard space and weight allocated to power generation, distribution, and conversion equipment, the Navy requires innovative technology solutions that can cost-effectively increase power system density. The ultra-high-speed generator technology will provide building blocks that align with both these initiatives.

The objective of this topic is to push the speed limits of an ultra-high-speed energy conversion unit up to one million revolutions per minute (i.e. 1000 Krpm) with over 95% system efficiency utilizing advanced, high-speed power electronic switching technologies and control schemes. The result would be a power-dense generator that is lighter and smaller. Challenges include the need for efficient, physics-based computational models in electromagnetics, structures, and thermodynamics of directly interacting, high-speed power electronic devices. The success of this topic would contribute to the on-going development of green energy applications using renewable energy sources.

The key metrics for this effort are speed (1000 Krpm objective, 750 Krpm threshold) and power density (40 kW/kg objective, 30 kW/kg threshold).

The Navy will only fund proposals that are innovative, address R&D, and involve technical risk.

PHASE I: Perform a feasibility study and develop physics-based models in order to produce a generator design capable of meeting the metrics outlined above.

PHASE II: Produce a bench-top demonstration of the generator. The design should be at TRL 3 or 4 at the end of this phase.

PHASE III: Produce a prototype generator that is at TRL 5 or 6 and demonstrates performance in alignment with the metrics above.

PRIVATE SECTOR COMMERCIAL POTENTIAL/DUAL-USE APPLICATIONS: The high speed generator has direct applications in power generation and transportation, making it broadly applicable to the commercial world.

REFERENCES:
1. C. Peter Cho, B. K. Fussel, and J. Y. Hung, "A novel integrated electric motor/pump for underwater applications," AIP Journal of Applied Physics, vol. 79, no. 8, April 1996.

2. C. P. Cho , B. Fussel, and J. Y. Hung, "Detent torque and axial force effects in a dual air-gap axial-field brushless motor," IEEE Transactions on Magnetics, vol. 29, no. 6, Nov 1993, pp. 2416-2418.

3. C. Peter Cho, David R. Crecelius, "Vehicle alternator/generator trends toward next millennium", IEEE, IVEC Proc., Jan 1999.

4. William P. Krol, C. Peter Cho, "High energy density permanent magnetic motors for underwater systems", IEEE, AUV Conf., 1996.