67 lines
3.0 KiB
Plaintext
67 lines
3.0 KiB
Plaintext
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(word processor parameters LM=8, RM=78, TM=2, BM=2)
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Taken from KeelyNet BBS (214) 324-3501
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Sponsored by Vangard Sciences
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PO BOX 1031
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Mesquite, TX 75150
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August 3, 1990
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Courtesy of NASA BBS at 205 895-0028
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POWER PROCESSING
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Power processors for primary-propulsion thrusters have been
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under development for several years. Early tests defined the power
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supply characteristics and control logic systems required to operate
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over large ranges of power and thrust.
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Processors capable of operating in vacuum have been developed.
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These processors, which include 12 separate power supplies and
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associated control logic, have electrical efficiences from 0.8 to
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0.92 over the thruster operating range.
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Although these efficiences are high, the large power requirement
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of the thruster (2.75 kW) implies that significant amounts of heat
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must be removed from each power processor. Meeting the thermal
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control requirements of the power processor challenges the designer,
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and a number of studies have been made to formulate systems
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approaches.
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One candidate concept uses variable-conductance heat pipes
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similar to those used on the Communications Technology Satellite
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(CTS), launched in 1976.
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The power processors in the concept are buried within the
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spacecraft body, and their waste heat is transported by heat pipes
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to radiators for injection to space (ref. 10). This concept, which
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among other features, such as eliminating the need for thermal-
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control louvers, provides excellent isolation of the power
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processors from the environment. And, thus, the impact of the
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multiple-mission capability requirement on spacecraft design
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is minimized.
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If you have comments or other information relating to such topics as
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this paper covers, please upload to KeelyNet or send to the Vangard
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Sciences address as listed on the first page. Thank you for your
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consideration, interest and support.
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Jerry W. Decker.........Ron Barker...........Chuck Henderson
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Vangard Sciences/KeelyNet
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If we can be of service, you may contact
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Jerry at (214) 324-8741 or Ron at (214) 484-3189
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