NASA SBIR 2005 Solicitation


SUBTOPIC TITLE:Spacecraft Propulsion
PROPOSAL TITLE:Wide Output Range Power Processing Unit for Electric Propulsion

SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
Colorado Power Electronics, Inc.
120 Commerce Drive, Unit 3
Fort Collins, CO 80524-4731
(970) 482-0191

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Geoff   Drummond
120 Commerce Drive, Unit 3
Fort Collins, CO  80524-4731
(970) 482-0191

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
A power supply concept capable of operation over 25:1 and 64:1 impedance ranges at full power has been successfully demonstrated in our Phase I effort at efficiencies of 96% and above. The benefits of electric propulsion systems are highest when an electric thruster can be operated at high efficiencies over wide ranges of thrust and specific impulse. Hall and ion thruster technologists are close to demonstrating this capability with laboratory and flight model thrusters, and power conversion systems based on the power supply concept demonstrated in our Phase I program will enable wide-ranging operation of these devices. Although ambitious missions with extreme throttling capabilities would now be possible with the CPE wide ranging power supply (WRPS) design, less ambitious (single throttle point) missions are also well served. This is because one power supply design could meet the needs of many different single-throttle-point devices without the need to re-design and re-qualify hardware. We judge that this innovation will save NASA, DoD, and commercial aerospace entities precious non-recurring engineering resources without sacrificing performance.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
The primary market for this technology is for space power conversion where low cost power processing is required. Present technology includes PPU designs with real costs that are much greater than $200k per kilowatt of power. The previous designs show poor reuse of modules and power hardware. The current trend for space power conversion is towards hybridization for the most compact and low mass PPU design. The NRE cost per hybrid can be as high as $100K per unique design, and the total NRE charge for hybrids in a complete ion or Hall engine PPU could easily exceed $1.5 million dollars. The recurring cost per hybrid is considerable lower than the hybrid design cost. The NRE when amortized over many units becomes more palatable and PPU costs can be made to be acceptably low. The new design proposed herein will use lower loss elements to simplify fabrication and reduce cost. In addition, the proposed "wide range design" will accommodate the addition and subtraction of modules while conserving PPU mass.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
ELECTRIC VEHICLES: A wide DC power range maximizes the power range for both the motor and the motor's inverter over a wide span of angular velocities. This wide and efficient range reduces the number of transmission shift cycles needed for rapid acceleration.
ROBOTICS: Our wide range power converter can supply emergency power to electromechanical drive systems with the minimum stress on the electrical power train. When critical power is needed to avoid mission ending obstacles, our wide range converter can supply the necessary torque or speed required for evasive maneuvering.
GRID FLAKE CLEARING: Many power systems for gridded thrusters require a flake busting power converter that is separate from the main power system. When a short occurs the main supplies are then deactivated. Next an auxiliary power converter is switched into the circuit by mechanical relays. The auxiliary supply, which is capable of producing large currents, cleans the flake through a process of evaporation. The wide range supply is also capable of producing large currents and does not need the reliability reducing mechanical switch gear.

NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.

Electromagnetic Thrusters
Electrostatic Thrusters
Photovoltaic Conversion
Power Management and Distribution
Radiation-Hard/Resistant Electronics
Renewable Energy
Thermoelectric Conversion
Ultra-High Density/Low Power

Form Printed on 07-25-06 17:04