Direct conversion of plasma energy to electricity for mirror fusion reactors

Conference · Wed Jan 01 04:00:00 EST 1975

OSTI ID:4093305

Moir, R W; Barr, W L; Carlson, G A

Direct conversion of both plasma and ion beam energy to electricity for mirror fusion reactors is described. Selective leakage, magnetic expansion, electron separation, deceleration, and collection of ions are discussed. An experiment testing all processes except selective leakage gave an overall efficiency of 86.5 +- 1.5 percent for a 22-stage collector. Computer calculations of these same processes gave an efficiency of 88.6 +- 1.5 percent, considered excellent agreement. Experiments on a two-stage collector gave 65 percent efficiency compared to 69 percent calculated efficiency. One-, two-, and 22-stage converters were studied under reactor-like conditions with a large computer simulation code that accounts for space charge, secondary electrons, and finite, realistic electrode shapes. The converters' efficiencies are estimated to be 48 percent, 58 percent and 63 percent, respectively. The efficiencies under the assumed reactor conditions are lower than under controlled laboratory conditions (86.5 percent). The one-stage converter is more cost-effective than the two-stage converter, which, in turn, is more cost-effective than the 22-stage converter; although more collector stages give higher efficiency, the simpler converters can handle more power. Conversely, if higher efficiency were desired, the studies show that it can always be achieved--but at a price. Laboratory tests of mono-energetic beam direct conversion gave 96 percent efficiency for a 2- keV low power d.c. beam and 70 percent for a d.c. 20 keV, 1-kW beam. The same computer code mentioned above is being used to design practical direct converters that reduce power requirements of neutral-beam injectors in the 100 to 200-keV range. (auth)

• Research Organization: Univ. of California, Livermore
• NSA Number: NSA-33-014580
• OSTI ID: 4093305
• Country of Publication: IAEA
• Language: English

Related Subjects

*DIRECT ENERGY CONVERSION-- EFFICIENCY
*MAGNETIC MIRRORS-- DIRECT ENERGY CONVERSION
700207* --Fusion Energy--Fusion Power Plant Technology-- Power Conversion Systems
COMPUTER CALCULATIONS
ELECTRONS
IONS
N70800* --Physics--Controlled Thermonuclear Research-- Thermonuclear Engineering & Equipment
NEUTRAL ATOM BEAM INJECTION