NASA SBIR 2012 Solicitation


PROPOSAL NUMBER: 12-1 E1.01-9064
SUBTOPIC TITLE: High Power Electric Propulsion Systems
PROPOSAL TITLE: High Input Voltage Hall Thruster Discharge Converter

SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
Busek Company Inc.
11 Tech Circle
Natick, MA 01760 - 1023
(508) 655-5565

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Thomas Jaquish
11 Tech Circle
Natick, MA 01760 - 1023
(508) 655-5565

CORPORATE/BUSINESS OFFICIAL (Name, E-mail, Mail Address, City/State/Zip, Phone)
Judy Budny
11 Tech Circle
Natick, MA 01760 - 1023
(508) 655-5565

Estimated Technology Readiness Level (TRL) at beginning and end of contract:
Begin: 3
End: 4

Technology Available (TAV) Subtopics
High Power Electric Propulsion Systems is a Technology Available (TAV) subtopic that includes NASA Intellectual Property (IP). Do you plan to use the NASA IP under the award?

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
The overall scope of this Phase I/II effort is the development of a high efficiency 15kW (nominal) Hall thruster discharge converter. In Phase I, Busek Co. Inc. will design, fabricate and test a nominal 7.5kW breadboard discharge converter module. Busek proposes a converter topolgy called the Leading Edge Auxiliary Phase Shifted (LEAPS) Bridge, which is a modification of the standard phase shifted bridge that uses an energy-recovering auxiliary circuit to force the transition from output inductor freewheel to power flowing through the main transformer. Based on preliminary measurements with this topology the converter module demonstrated >97% efficiency at reduced power.
A 300V line input and 300-400V output range are the benchmark for the discharge converter in Phase 1. The most reasonable path with higher input voltage for higher power converters involves the use Wide Band Gap FETs. MOSFETS represent the greatest payoff in terms of efficiency improvements and are a primary focus for a discharge converter to achieve an efficiency of 98% or greater. With the design maturity gained from the Phase I breadboard, the Phase II objective will be the production of a 15kW brassboard PPU in a flight-like form factor that incorporates conductive cooling.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
NASA has identified 30kW-class SEP systems as a high-value intermediate step toward higher power systems due to broad cross-cutting capability. Current NASA investments include advanced next-generation solar arrays and higher power electric propulsion technologies to enable 30kW-class SEP. The ESPA ring is one approach being considered for partner-based mission concepts and those capable of being launched as secondary payloads. In addition NASA is investing in EP development of 15kW class HET system using either direct-drive and/or high voltage power processing unit.
The possibility for using Hall thrusters for lunar and Mars missions has also been well investigated. Hall thrusters have been found to be a good choice for Mars cargo missions and other studies have found Hall thrusters to be viable options for supporting lunar and Mars exploration. Another NASA study indicates that a cluster of eight 100 kW Hall thrusters would be well sized for manned Mars missions.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
A nominal 15kW thruster with the capability to throttle down to 5kW should find broad applications on DoD and commercial ComSats. Hall thrusters could enhance many high power DoD and commercial missions such as satellite servicing, orbit maintenance, orbit raising and lowering, inclination changes, and repositioning. The system could also find near term application on an all-electric upper stage derived from Busek's ESPA orbit maneuvering system (OMS), a free flying spacecraft based on the ESPA ring that is being developed in cooperation with United Launch Alliance (ULA). A low power system presently utilizes four BHT-1500 Xe Hall effect thrusters and capable of delivering up to five ESPA class spacecraft to multiple orbits. The high power (30kW) version would be used for transportation of propellant to a LaGrange positioned fuel depot.

TECHNOLOGY TAXONOMY MAPPING (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.)
Autonomous Control (see also Control & Monitoring)
Circuits (including ICs; for specific applications, see e.g., Communications, Networking & Signal Transport; Control & Monitoring, Sensors)
Coatings/Surface Treatments
Maneuvering/Stationkeeping/Attitude Control Devices
Manufacturing Methods
Materials & Structures (including Optoelectronics)
Materials (Insulator, Semiconductor, Substrate)
Space Transportation & Safety
Spacecraft Design, Construction, Testing, & Performance (see also Engineering; Testing & Evaluation)
Spacecraft Main Engine

Form Generated on 03-28-13 15:21